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In thoracoscopic segmentectomy, accurate preoperative identification of intersegmental vessels, bronchi, and the surgical safety margin is vital. We applied three dimensional computed tomography bronchography and angiography (3D-CTBA) reconstruction to appropriately plan thoracoscopic segmentectomy for Patients with pulmonary nodules. In this study, we evaluated the effectiveness and accuracy of 3D-CTBA reconstruction for the identification of segmental anatomical structures and variation during thoracoscopic segmentectomy.We retrospectively analyzed data of 30 patients who underwent 3D-CTBA reconstruction before thoracoscopic segmentectomy between January and May 2019 in the Department of Thoracic Surgery, First Affiliated Hospital of Nanchang University. We compared the individual target segment arteries, veins, and bronchi identified during surgery with the preoperative 3D-CTBA model to evaluate its effectiveness and accuracy. The accuracy of the preoperative 3D-CTBA model for the identification of target segmental arteries, veins, and bronchi was 99.08% (108/109), 98.39% (122/124), and 100% (118/118), respectively. Through 3DCTBA modeling, we found mediastinal and interlobar types of lingular segmental arteries in six patients, and central veins were not found in seven patients. In addition, we detected rare anatomical variations in two patients; one patient had the right apical segmental bronchus that stemmed solely from the right primary bronchus (tracheal bronchus), and the other had rare right basal segmental variant bronchi and vessels. The 3D-CTBA model can precisely predict segmental bronchi and vessels and identify anatomical structure variations before operation, which can aid surgeons to avoid incorrect operation and improve surgical efficiency. This has important implications for thoracoscopic segmentectomy.

BACKGROUND MicroRNA-145 (miR-145) has been shown to play a critical role in ischemia/reperfusion (I/R) injury; however, the expression and function of miR-145 in lung I/R injury have not been reported yet. This study aimed to elucidate the potential effects of miR-145 in lung I/R injury. METHODS Lung I/R mice models and hypoxia/reoxygenation (H/R) pulmonary microvascular endothelial cell models were established. The expression of miR-145 and sirtuin 1 (SIRT1) was measured with reverse transcription-quantitative polymerase chain reaction and Western blot analysis in mouse lung tissue and cells. Artificial modulation of miR-145 and SIRT1 (downregulation) was done in I/R mice and H/R cells. Additionally, Pao2/FiO2 ratio, wet weight-to-dry weight ratio, and cell apoptosis in mouse lung tissues were determined by blood gas analyzer, electronic balance, and deoxyuridine triphosphate-biotin nick end-labeling assay, respectively. Autophagy marker Beclin 1 and LC3 expression, NF-κB acetylation levels, and autophagy bodies were detected in cell H/R and mouse I/R models by Western blot analysis. pulmonary microvascular endothelial cell apoptosis was detected with flow cytometry. RESULTS miR-145 was abundantly expressed in the lung tissue of mice and PMVECs following I/R injury. In addition, miR-145 directly targeted SIRT1, which led to significantly decreased Pao2/FiO2 ratio and increased wet weight-to-dry weight ratio, elevated acetylation levels and transcriptional activity of NF-κB, upregulated expressions of tumor necrosis factor-α, interleukins-6, and Beclin 1, autophagy bodies, cell apoptosis, as well as LC3-II/LC3I ratio. CONCLUSIONS In summary, miR-145 enhances autophagy and aggravates lung I/R injury by promoting NF-κB transcriptional activity via SIRT1 expression.

Two new Middle Permian foraminifer faunas are described from the Xiala Formation in the Zhabuye and Xiadong sections in the central Lhasa Block. The presence of some significant taxa in paleobiogeography such as Shanita, Lysites biconcavus, Hemigordiopsis subglobosa, indicates that the Lhasa Block was in the Cimmerian Province in paleobiogeography during the Middle Permian. Furthermore, the Nankinella-Chusenella fusuline assemblage that occurs in the upper part of the Xiala Formation in the Xiadong section resembles contemporaneous fusuline faunas from the Xainza and Bashor areas in the Lhasa Block and the northern part of the Tengchong Block. The endemism of the Nankinella-Chusenella assemblage in the Lhasa and Tengchong blocks indicates that these two blocks were isolated from both the South Qiangtang Block and the northern Gondwanan margin during the Middle Permian. It further suggests that both the Bangong-Nujiang Ocean and the Neotethys Ocean would have opened before the Middle Permian. A new species Chusenella tsochenensis sp.nov. was described.

In non-small-cell lung carcinoma (NSCLC), aberrant activation of mammalian target of rapamycin (mTOR) contributes to tumorigenesis and cancer progression. PQR620 is a novel and highly-potent mTOR kinase inhibitor. We here tested its potential activity in NSCLC cells. In primary human NSCLC cells and established cell lines (A549 and NCI-H1944), PQR620 inhibited cell growth, proliferation, and cell cycle progression, as well as cell migration and invasion, while inducing significant apoptosis activation. PQR620 disrupted assembles of mTOR complex 1 (mTOR-Raptor) and mTOR complex 2 (mTOR-Rictor-Sin1), and blocked Akt, S6K1, and S6 phosphorylations in NSCLC cells. Restoring Akt-mTOR activation by a constitutively-active Akt1 (S473D) only partially inhibited PQR620-induced cytotoxicity in NSCLC cells. PQR620 was yet cytotoxic in Akt1/2-silenced NSCLC cells, supporting the existence of Akt-mTOR-independent mechanisms. Indeed, PQR620 induced sphingosine kinase 1 (SphK1) inhibition, ceramide production and oxidative stress in primary NSCLC cells. In vivo studies demonstrated that daily oral administration of a single dose of PQR620 potently inhibited primary NSCLC xenograft growth in severe combined immune deficient mice. In PQR620-treated xenograft tissues, Akt-mTOR inactivation, apoptosis induction, SphK1 inhibition and oxidative stress were detected. In conclusion, PQR620 exerted potent anti-NSCLC cell activity via mTOR-dependent and -independent mechanisms.

This work presents an investigation on the composition and structure of polysaccharides from the roots of Tetrastigma hemsleyanum (THP) and its associated antioxidant activity. It further explores the protective effect of THP on RAW264.7 cells against cytotoxicity induced by H2O2. Ion chromatography (IC) revealed that THP contained glucose, arabinose, mannose, glucuronic acid, galactose and galacturonic acid, in different molar ratios. Furthermore, gel permeation chromatography-refractive index-multiangle laser light scattering (GPC-RI-MALS) was employed to deduce the relative molecular mass (Mw) of the polysaccharide, which was 177.1 ± 1.8 kDa. Fourier transform infrared spectroscopy (FT-IR) and Congo red binding assay highlighted that the THP had a steady α-triple helix conformation. Similarly, assays of antioxidant activity disclosed that THP had reasonable concentration-dependent hydroxyl radical and superoxide radical scavenging activities, peroxidation inhibition ability and ferrous ion chelating potency, in addition to a significant 1,1-diphenyl-2-picrylhydrazyl radical scavenging capacity. Moreover, THP could protect RAW264.7 cells against H2O2-induced cytotoxicity by decreasing intracellular ROS levels, reducing catalase (CAT) and superoxide dismutase (SOD) activities, increasing lactate dehydrogenase (LDH) activity and increment in malondialdehyde (MDA) level. Data retrieved from the in vitro models explicitly established the antioxidant capability of polysaccharides from T. hemsleyanum root extracts.

Lung ischemia-reperfusion (I/R) injury severely endangers human health, and recent studies have suggested that certain microRNAs (miRNAs) play important roles in this pathological phenomenon. The current study aimed to ascertain the ability of miR-223 to influence lung I/R injury by targeting hypoxia-inducible factor-2α (HIF2α). First, mouse models of lung I/R injury were established: during surgical procedures, pulmonary arteries and veins and unilateral pulmonary portal vessels were blocked and resuming bilateral pulmonary ventilation, followed by restoration of bipulmonary ventilation. In addition, a lung I/R injury cell model was constructed by exposure to hypoxic reoxygenation (H/R) in mouse pulmonary microvascular endothelial cells (PMVECs). Expression of miR-223, HIF2α, and β-catenin in tissues or cells was determined by RT-qPCR and Western blot analysis. Correlation between miR-223 and HIF2α was analyzed by dual luciferase reporter gene assay. Furthermore, lung tissue injury and mouse PMVEC apoptosis was evaluated by hematoxylin and eosin (H&E), TUNEL staining, and flow cytometry. Autophagosomes in cells were detected by light chain 3 immunofluorescence assay. miR-223 was expressed at a high level while HIF2α/β-catenin was downregulated in tissues and cells with lung I/R injury. Furthermore, miR-223 targeted and repressed HIF2α expression to downregulate β-catenin expression. The miR-223/HIF2α/β-catenin axis aggravated H/R injury in mouse PMVECs and lung I/R injury in mice by enhancing autophagy. Taken together, miR-223 inhibits HIF2α to repress β-catenin, thus contributing to autophagy to complicate lung I/R injury. These findings provide a promising therapeutic target for treating lung I/R injury.

A series of novel 1,4-benzodioxane thiazolidinedione piperazine derivatives targeting FabH were designed and synthesized. The compounds exhibited better inhibitory activity against Gram-negative bacteria by computer-assisted screening, antibacterial activity test and E. coli FabH inhibitory activity test, wherein compound 6j exhibited the most significant inhibitory activity (MIC = 1.80 μΜ for P. aeruginosa, MIC = 1.56 μΜ for E. coli). Besides, compound 6j still showed the best E. coli FabH inhibitory activity (IC50 = 0.06 μΜ). Moreover, the antibacterial activities of all compounds were strongly correlated with the inhibitory ability of FabH, with a correlation coefficient of 0.954. Computational docking studies also showed that compound 6j has interacting with FabH key residues in the active site.

The Box–Behnken design was used to optimize the extraction conditions of total flavonoids from Tetrastigma hemsleyanum. The effects of four independent variables, including extraction temperature, extraction time, number of extraction and the ratio of liquid to raw material, on flavonoids yield were determined. The experimental data were fitted to a second-order polynomial equation using multiple regression analysis and also analyzed using the appropriate statistical methods. The optimum extraction conditions were at extraction temperature of 80C, extraction time of 2.1 h, number of extraction of 3 and ratio of liquid to raw material of 17.6 mL/g. Under these conditions, the experimental flavonoids yield was 1.23 ± 0.09%, which was in good agreement with the predicted value. The antioxidant activities of the flavonoids, including the scavenging activity of ABTS (2,2′-azinobis(3-ethyl-benzothiazoline-6-sulfonic acid) diammonium salt), DPPH (1,1-diphenyl-2-picrylhydrazyl) and ferric reducing antioxidant power assay, were examined. The data obtained from our study clearly demonstrate the antioxidant potency of the flavonoids extracted from the roots of T. hemsleyanum. Practical Applications Many studies have been carried out to find new sources of natural antioxidants because they are environmentally friendly and have no health hazards. In particular, interest has intensified in the flavonoids present in the normal human diet and in many folk medicines still in use. Tetrastigma hemsleyanum is a herbaceous perennial species native to China. In this study, the extraction conditions of flavonoids from the roots of T. hemsleyanum were optimized and studies demonstrated that the flavonoids possessed potent antioxidant activity. Therefore, the flavonoids have the potential to be used in food systems.

Box–Behnken design including independent variables such as extraction temperature (80–100C, X1), extraction time (1.5–2.5 h, X2) and ratio of water to raw material (15–25 mL/g, X3) was employed to optimize the extraction of polysaccharides from the leaves of Artemisia argyi (AAP). The optimized extraction parameters were as follows: extraction temperature of 100C, extraction time of 2.27 h and ratio of water to raw material of 21.5 mL/g. The experiment extraction yield of AAP was 2.15 ± 0.09% under the optimal conditions, which was agreed closely with value predicted by the model. Additionally, polysaccharide was analyzed by Fourier transform infrared. The antioxidant activities of AAP were performed including scavenging activity of 2,2′-azino-bis (3-ethylbenzthiazoline-6-sulfonic) acid, reducing power and metal-chelating assay. The data obtained in the in vitro models clearly demonstrate the antioxidant potency of the polysaccharides extracted from moxa leaf. Practical Applications In recent years, many research have been carried out to find new sources of natural antioxidants. In particular, interest has intensified in the polysaccharides present in normal human diet and in many folk medicines still in use. Moxa leaf has a number of recorded historic uses in food, herbal medicine and as a smoking herb. In this study, the extraction conditions of polysaccharides from the leaves of Artemisia argyi (AAP) were optimized and the AAP exhibited potent antioxidant activity. Therefore, the polysaccharide has the potential to be used in food systems.

The molecular mechanism to induce apoptosis in human hepatoma SMMC-7721 cells was investigated using 2′,4′-Dihydroxy-6′-methoxy-3′,5′-dimethylchalcone (DMC) isolated from the buds of Cleistocalyx operculatus. Typical morphological changes in apoptotic body formation after DMC treatment were observed using acridine orange (AO)/ethidium bromide (EB) staining. After 48 h of incubation with 0, 6.25, 12.5, and 25 μM of DMC, the percentages of annexin V-FITC-positive/PI negative cells were 1.51, 9.33, 33.84, and 61.32%, respectively. Apoptosis induced by DMC was blocked by z-VAD-fmk, a caspase inhibitor. Analysis of fluorescence intensities of rhodamine 123 in cells showed that DMC induced a loss of mitochondrial membrane potential (ΔΨm). Western blot results showed that DMC decreased the Bcl-2/Bax ratio, suggesting that the Bcl-2 family is involved in control of apoptosis. All of these signal transduction pathways are involved in initiating apoptosis. DMC is a potential anticancer agent that deserves further exploration.

The aim of this work was to study the antioxidant activity and the protective effect of 2′,4′-dihydroxy-6′-methoxy-3′,5′-dimethylchalcone (DMC), the main compound from the buds of Cleistocalyx operculatus, on human umbilical vein endothelial cells against cytotoxicity induced by H2O2. The antioxidant activities of DMC were measured by ABTS assay, ferric reducing antioxidant power (FRAP) and hydroxyl radical scavenging activity, and protective effects of DMC on human umbilical vein endothelial cells against cytotoxicity induced by H2O2 were tested. DMC was found to have high ABTS radical scavenging activity (176.5 ± 5.2 μmol trolox equivalents/500 μmol DMC) and strong ferric reducing antioxidant power (213.3 ± 5.8 μmol trolox equivalents/500 μmol DMC). In addition, DMC scavenged the hydroxyl radicals, with IC50 values of 243.7 ± 6.3 μM, slightly lower than the reference antioxidant ascorbic acid (ASC). Moreover, DMC could protect the human umbilical vein endothelial cells against H2O2-induced cytotoxicity by decrease intracellular and extracellular ROS levels, reduction in catalase (CAT) activity and increment in malondialdehyde (MDA) level. These results suggested that DMC has the potential to be used in the therapy of oxidative damage.

The aims of this study were to test the efficacy of essential oil of Allium cepa against food spoilage and food-borne pathogenic microorganisms and its antioxidant activity. The essential oil revealed an interesting antimicrobial effect against the tested microorganisms with the MIC and MBC values in the ranges of 0.18–1.80 mg/mL and 0.54–3.6 mg/mL, respectively. The antioxidant activities of the essential oil were investigated and the oil showed moderate antioxidant activities in ABTS assay (0.67 mg/mL as IC 50 value), DPPH test (IC 50 value = 0.63 mg/mL) and metal chelating assay (IC 50 value of 0.51 mg/mL). Furthermore, the reducing power of the oil was dose dependent, and the reducing capacity of the oil was inferior to butylated hydroxytoluene, which is known to be a strong reducing agent. It was suggested that the essential oil from A. cepa may be a new potential source as natural antimicrobial and antioxidant agents applied in food systems.

The response surface methodology was employed to study the extraction of polysaccharides from Scutellaria barbata D. Don. The quantitative effects of extraction temperature, time, number and ratio of water to raw material on yield of polysaccharides were investigated with Box–Behnken design. The experimental data were fitted to a second-order polynomial equation using multiple regression analysis and also analyzed using the appropriate statistical methods. By solving the regression equation and analyzing 3D plots, the optimum condition was at extraction temperature 70 °C, time 3 h, numbers 3 and ratio of water to raw material 18.5 mL/g. Under these conditions, the experimental polysaccharides yield was 2.43 ± 0.11%, which was in good agreement with the predicted value. The antioxidant activities of the polysaccharides were evaluated in vitro. A potential antioxidant activity of S. barbata polysaccharides provides a scientific basis for the use of this herb in traditional medicine as an antioxidant.

Response surface methodology was employed to optimize the conditions of supercritical CO2 extraction of the oil from freeze-dried onion powder. The effects of pressure, temperature and extraction time on the yield of oil were investigated. The maximum extraction yield of 4.69 ± 0.04 g/kg dry basis was achieved at a pressure of 20.6 MPa, a temperature of 40.6 °C, a time of 260 min, a CO2 flow rate of 22 L h–1, and an entrainer ratio of 0.1 mL absolute ethanol per gram dry basis. The chemical composition of the oil was analyzed by gas chromatography-mass spectrometry. The most representative compounds of the essential oil were organosulfur-containing compounds and, among these, the main constituents were methyl 5-methylfuryl sulfide (18.30 %), methyl 3,4-dimethyl-2-thienyl disulfide (11.75 %) and 1-propenyl propyl disulfide (9.72 %).

Polysaccharide production from the aerial parts of Plantaoo asiatica L. was carried out using water decoction. Response surface methodology (RSM), based on a five level, four variable central composite design (CCD), was employed to obtain the best possible combination of extraction time (X1: 1–5 h), extraction temperature (X2: 60–100 °C), number of extraction (X3: 1–5), and ratio of water to raw material (X4: 10–30) for maximum polysaccharide production. The experimental data obtained were fitted to a second-order polynomial equation using multiple regression analysis and also analyzed by appropriate statistical methods (ANOVA). The optimum extraction conditions were as follows: extraction time of 3.9 h, extraction temperature of 91 °C, number of extraction of 4, and ratio of water to raw material of 24. Under these conditions, the experimental yield was 4.37 ± 0.13%, which is well in close agreement with value predicted by the model.

Previously, we showed that 2',4'-dihydroxy-6'-methoxy-3',5'-dimethylchalcone (DMC), isolated from the buds of Cleistocalyx operculatus, significantly inhibited the growth of human liver cancer SMMC-7721 cells and could induce SMMC-7721 cells apoptosis in vitro. Here, we report the antitumor effects of DMC in vivo, using a solid human tumor xenograft model with a human liver cancer SMMC-7721 cell line. Our results revealed that the average tumor weight in a control group and a 150-mg/kg DMC injection group was 1.42+/-0.11 g and 0.59+/-0.12 g, respectively. Flow cytometric analysis of the tumor cell population demonstrated the existence of an aneuploid peak (representing 33.60+/-0.80% of the total in the 150-mg/kg DMC injection group). To our knowledge, this is the first time that chalcone compounds were applied to a human tumor xenograft model.

To study the in-vitro inducing apoptosis mechanism of human hepatoma SMMC-7721 cells by 2',4'-di- hydroxy-6'-methoxy-3',5'-dimethylchalcone (DMC), a chalcone compound from Cleistocalyx operculatus.Quantitative DNA fragmentation assay was carried out to detect the effect of DMC of different concentrations on SMMC-7721 cells, according to the method of Sellins and Cohen with some modifications. Telomerase activities of the cells were determined by PCR-ELISA methods. The expression quantity of c-myc and hTERT mRNA were determined by semi-quantitative RT-PCR The effect of DMC on expression levels of cmyc and hTERT protein were measured by western blot.The percentage of DNA fragmentation increased with notable concen- tration dependence, after treatment with DMC for 48 h. Compared with that of control group, the telomerase activity of the cells de- creased by (66.2 ± 2.1)% after 48 h treatment with 20 μmol x L(-1) DMC, the mRNA expression of c-myc and hTERT decreased by (67.3 ± 2.1)% and (64.4 ± 2.3)%, respectively, and the protein expression of c-myc and hTERT decreased by (69.6 ± 1.9)% and (71.3 ± 2.4)%, respectively.DMC can induce SMMC-7721 cell apoptosis and the apoptosis mechanism may be related to the decreased mRNA and protein expression of c-myc and hTERT.

Nowadays, much effort is being devoted to detect new substances that not only significantly induce the death of tumor cells, but also have little side effect on normal cells. Our previous study showed that 2′,4′-dihydroxy-6′-methoxy-3′,5′-dimethylchalcone (DMC) exhibited significant cytotoxic potential with an IC50 value of 32.3 ± 1.13 μM against SMMC-7721 cells and could induce SMMC-7721 cells apoptosis. In the present study, we found that DMC was almost nontoxic to human normal liver L-02 and human normal fetal lung fibroblast HFL-1 cells as their IC50 values (111.0 ± 4.57 and 152.0 ± 4.83 µM for L-02 and HFL-1 cells, respectively) were much higher. To further explore the apoptotic mechanism of DMC, we investigated the role of the reactive oxygen species (ROS) in the apoptosis induced by DMC in SMMC-7721 cells. Our results suggested that the cytotoxicity and the generation of intracellular ROS were inhibited by N-acetylcysteine (NAC). Reversal of apoptosis in NAC pretreated cells indicated the involvement of ROS in DMC-induced apoptosis. The loss of mitochondrial membrane potential (ΔΨm) induced by DMC was significantly blocked by NAC. NAC also prevented the decrease of Caspase-3 and -9 activities, the increase of Bcl-2 protein expression and the decrease of p53 and PUMA protein expressions. Together, these results indicated that ROS played a key role in the apoptosis induced by DMC in human hepatoma SMMC-7721 cells.

The extraction conditions of polysaccharides from Plantago asiatica L. seeds were investigated. Four parameters affecting the polysaccharides extraction, extraction times, water to sample, extraction temperature and single extraction time, were determined by orthogonal experiments. Under the optimized conditions, the polysaccharides yield of P. asiatica L. seeds was 2.467%. The antioxidant activities of the polysaccharides were investigated. The reducing power of the polysaccharides was dose dependent, and the reducing capacity of the polysaccharides was inferior to butylated hydroxytoluene, which is known to be a strong reducing agent. The scavenging rates of the polysaccharides on superoxide and 1,1-diphenyl-2-picrylhydrazyl radicals were 79.7% and 81.4%, at polysaccharides concentration of 0.75 mg/mL, respectively, a scavenging rates approximately similar to that of 0.75 mg/mL ascorbic acid (83.5% and 85.1%, respectively). Furthermore, it exhibited a moderate concentration-dependent ABTS radical scavenging activity, ferrous ion chelating potency and H(2)O(2) scavenging activity. The data obtained in the in vitro models clearly establish the antioxidant potency of the polysaccharides extracted from Semen Plantaginis.

Two new flavonoids - 3′-formyl-4′,6′-dihydroxy-2′-methoxy-5′-methylchalcone (FMC) and (2S)-8-formyl-5-hydroxy-7-methoxy-6-methylflavanone (FMF) - isolated from the buds of Cleistocalyx operculatus, were investigated for their antioxidant and anticancer activity. Total antioxidant activity and reducing ability were measured. 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and superoxide anion radical scavenging assays were carried out to evaluate the antioxidant potential of the two compounds. The antioxidant activity of the two compounds increased in a concentration-dependent manner. FMC and FMF at a concentration of 500 μM inhibited lipid peroxidation by 64.3 ± 2.5% and 60.3 ± 2.3%, respectively, an antioxidant activity approximately similar to that of 500 μM α-tocopherol (66.3 ± 2.5%). Similarly, the effect of FMC and FMF on reducing power increased in a concentration-dependent manner. In DPPH radical scavenging assays, the IC50 values of FMC and FMF were 50.2 ± 2.8 μM and 75.8 ± 2.5 μM, respectively. Moreover, FMC and FMF scavenged the superoxide generated by the phenazine methosulfate (PMS)/reduced β-nicotinamide adenine dinucleotide (NADH) nitroblue tetrazolium (NBT) system, with IC50 values of 56.3 ± 2.3 μM and 317.5 ± 2.9 μM, respectively. The anticancer activity of the two compounds were determined in five human cancer cell lines, SMMC-7721 (liver cancer), 8898 (pancreatic cancer), K562 (chronic leukaemia), HeLa (tumour of cervix uteri) and 95-D (high metastic lung carcinoma). FMC and FMF showed broad-spectrum anticancer activity against all the human cancer cell lines tested. The results obtained in the current study indicate that the two flavonoids could be a potential source of natural antioxidant and anticancer agents. To our knowledge, this is the first report on bioactivity of FMC and FMF.

To observe the protective effects of Cleistocalyx operculatus on lipid peroxidation in rat liver microsomes and on the trauma of PC12 cells induced by H2O2.The mouse liver homogenate lipid peroxidation assay and PC12 Cell culture and Cell viability (MTT assay) were applied.Cleistocalyx operculatus showed strong protective effects on lipid peroxidation in rat liver microsomes in a dose-dependent manner and exhibited potent protective effects on the trauma of PC12 cells induced by H2O2 (200 micromol x L(-1)) when the concentration reached 1.00 g x L(-1).Cleistocalyx operculatus may be used as antioxidant to prevent or delay the pathogenesis of neural cell diseases.

To investigate the changes of function of large conductance of calcium-activated potassium channels (BK(Ca) channels) in thoracic aortic smooth muscle cells in early stage of streptozotocin (STZ)-induced diabetic C57BL/6J mice.Vascular muscle tension in the isolated thoracic aortic rings of mice was compared, and the role of BK(Ca) channels in relaxation of isolated mice thoracic aortic rings induced by acetylcholine (ACh) was determined. Meanwhile, single vascular smooth muscle cells (VSMCs) were isolated by collagenase, and BK(Ca) currents were recorded by patch-clamp single channel recording technique in symmetric high potassium solution.Tetraethylammonium (TEA) 1 mmol/L, a selective calcium-activated potassium channel blocker, caused significant rightward shift in the concentration-response curves of ACh in the isolated thoracic aortic rings of diabetic mice and pD2 value of ACh-induced relaxation was decreased notably after TEA treatment [(6.3+/-0.4) vs (6.9+/-0.5), n=10 rings from 7 mice, P0.01]. But pD2 value of ACh-induced relaxation in age-matched control mice did not change in presence and absence of TEA 1 mmol/L [(6.4+/-0.15) vs (6.5+/-0.5), n=7 rings from 6 mice, P0.05]. Furthermore, conductance of BK(Ca) channels in single thoracic aortic smooth muscle cells was decreased [(199+/-15) pS, n=10 cells from 7 mice vs (266+/-11) pS, n=12 cells from 6 mice, P0.01], but probability of open of BKCa channels was increased [(0.51+/-0.28) vs (0.11+/-0.06), n=6 cells from 6 mice, P0.01], and the mean closed time in diabetic mice was reduced [(15+/-15) vs (132+/-98), n=6 cells from 6 mice, P0.05].The opening of BK(Ca) channels was increased in thoracic aortic smooth muscle cells in the early stage of STZ-induced diabetic C57BL/6J mice by reducing mean closed time, but the conductance of BK(Ca) channels was decreased.

2',4'-Dihydroxy-6'-methoxy-3',5'-dimethylchalcone (DMC), isolated from the buds of Cleistocalyx operculatus, was investigated in its cytotoxicity and its influence on six human cancer cell lines. Among SMMC-7721, 8898, HeLa, SPC-A-1, 95-D and GBC-SD cell lines, SMMC-7721 cells was the most sensitive one in these tested cell lines, with IC50 equal to 32.3 +/- 1.13 microM, EC50 equal to 9.00 +/- 0.36 microM and the therapeutic index equal to 3.59. Staining with Hoechst 33258 showed fragmentation and condensation of chromatin in the cells treated with 9 microM DMC for 48 h. Flow cytometric analysis was performed to determine hypodiploid cells. The results of flow cytometry assay indicated that the percentage of hypodiploid SMMC-7721 cells were 49.44 +/- 1.06% after 48 h treatment with 18.0 microM DMC. The treatment resulted in the appearance of a hypodiploid peak (A0 region), probably due to the presence of apoptosing cells and/or apoptotic bodies with DNA content less than 2n. To our knowledge, this is the first report on anti-tumor activity by DMC.

Two flavonoids 3'-formyl-4',6'-dihydroxy-2'-methoxy-5'-methylchalcone and (2S)-8-formyl-5-hydroxy-7-methoxy-6-methylflavanone together with five known compounds, were isolated from the dried buds of Cleistocalyx operculatus. Their structures were determined on the basis of spectroscopic analyses (UV, IR, EIMS, (1)H, (13)C NMR and HMBC).

Polyguanidine is used as a novel and highly efficient catalyst in the Knoevenagel reaction of aldehydes with active methylene compounds in water to afford substituted electrophilic alkenes. This method is applicable for a wide range of aldehydes including aromatic and heterocyclic substrates. The polyguanidine catalyst can be recovered by simple filtration and reused many times for the aqueous Knoevenagel reaction without loss of activity.