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Cajaninstilbene acid (CSA), Longistylin A (LLA) and Longistylin C (LLC) are three characteristic stilbenes isolated from pigeon pea, exhibiting antibacterial activities against Staphylococcus aureus and even methicillin-resistant Staphylococcus aureus (MRSA). The results showed that LLA had the highest antibacterial activity against the tested strains following by LLC and CSA. Besides, the results implied that these stilbenes effectively inhibited the levels of adhesion and virulence genes and downregulate the production of ɑ-hemolysin. This study showed that stilbenes from pigeon pea have anti-Staphylococcus potential, and they also inhibited bacterial proliferation, biofilm formation, and key gene expressions related to adhesion and virulence of MRSA. It is the first time that the anti-S. aureus and MRSA activities of the three stilbenes has been systematically reported. These current findings provide insight into the anti-MRSA mechanism of stilbenes from pigeon pea, indicating these compounds may be used as antimicrobial agents or additives for food with health functions, and contribute to the development as well as application of pigeon pea in food science.

Two new phenolic glycosides (

This research aims to investigate the association between hyperthyroidism and age, sex, and infraction of the myocardium in the Hong Kong population in order to detect hyperthyroidism-induced infraction earlier (e.g., thyrocardiac disease) through chemiluminescent microparticle immunoassay (CMIA). A total of 7616 random blood specimens from males and females were collected and examined by Architect i immunoassay platform to obtain quantitative laboratory values of Free FT4, TSH, and hs-cTnI in samples serum differentiating into overt and subclinical hyperthyroidism cases. The age was between 19 and 81 years old. In this research, for population characteristics, 57 cases confirmed as hyperthyroidism (e.g. FT4 > 1.48 ng/dL, according to Abbott’s suggested reference interval) were used for analysis and 22 cases were examined in the laboratory. The highest number of hyperthyroidisms including overt and subclinical cases in female was 43 (75.44%), rather than males. For prevalence data of hyperthyroidism between September 2019 to January 2020 in Hong Kong, the range was from 0.62% to 0.93% (Median percentage = 0.75%). The research will explore the in-depth impact of gender difference on thyrocardiac disease, risk of thyrocardiac disease by age group, and the possible relationship between FT4 and hs-cTnI.

Two new withaphysalin-type withanolides (18-O-ethylwithaphysalin R and 5-O-ethylphysaminimin C

Two new compounds (1 and 2), belonging to C-20 oxygenated ent-kauranes-type diterpenoids, were identified from the aerial parts of Isodon serra. Their structures were elucidated by extensive analysis of HRESI-MS and NMR spectroscopic data. Both these two compounds possess a common 7,20-epoxy-ent-kauranes skeleton with a hydroxyl group rarely occurring at C-13. Compounds 1 and 2 were evaluated for their cytotoxic activity against Hela-60 and HepG2 as well as the antibacterial activity against Staphylococcus aureus, Bacillus cereus and Escherichia coli.

One new 3,24-dinor-2,4-seco-ursane triterpene, rosanortriterpene C (1), together with four known compounds including 24-norursane-type nortriterpenes (2-3), 24-noroleanane-type nortriterpene (4), ursane-type triterpene (5), was isolated from the fruits of Rosa laevigata var. leiocapus. The new structure was elucidated through comprehensive spectroscopic analysis, including one dimensional (1D) and 2D NMR data, as well as electrospray ionization high resolution (HR-ESI) MS and IR spectrometry. Compounds 1-5 showed moderate anti-inflammatory activities against the production of nitric oxide (NO) in RAW264.7 cells stimulated by lipopolysaccharide (LPS) with IC50 values of 10.35 ± 0.92, 14.28 ± 1.20, 5.04 ± 1.43, 29.29 ± 3.64, and 14.37 ± 0.59 µM, respectively.

Many drugs for anti-tumour have been developed, nevertheless, seeking new anticancer drug is the focus of ongoing investigation. Withanolides have been reported to possess potent antiproliferative activity. Literature findings revealed that a diversity of withanolides were obtained fromThe EtOAc fraction ofOur findings might offer valuable clues for the utilization of withanolides as lead compounds for antineoplastic or antibacterial drug development.

Rosa laevigata Michx., a medicinal and edible plant in China, has exerted a variety of medicinal values and health benefits. This present review aims to achieve a comprehensive and up-to-date investigation in the phytochemistry and pharmacology of R. laevigata. According to these findings in the literature, approximately 123 chemical ingredients covering triterpenoids, flavonoids, tannis, lignans and polysaccharides, have been characterized from various parts of this species. Among these isolates, 77 triterpenoids have been isolated and thus regarded as the primary and characteristic substance. Based on the chemical structures, most of the obtained triterpenoids can be classified into polyhydroxy triterpenoids and readily divided into four categories: ursane-type, oleanane-type, lupinane-type, as well as seco-triterpenoids. The crude extracts and the purified compounds have demonstrated various pharmacological effects in vitro and in vivo, such as antioxidant activity, immunomodulatory effect, anti-inflammatory effect, liver protection, kidney protection, cardiovascular protection, neuroprotective effect and improvement of diabetic cataract. Noticeably, these pharmacological results of R. laevigata provide evidences for its traditional uses. In addition, these different chemical ingredients existing in the title plant may have synergistic effects. In conclusion, the chemical profiles, including ingredients and structures, together with the modern pharmacological properties have been adequately summarized. These evidences have revealed this plant to be a valuable source for therapeutic foodstuff and more attention should be paid to a better utilization of this plant.

By combining Biot's dynamic wave theory with the elastic and slip interface theory, the scattering of plane waves around a saturated lining structure embedded in saturated soil is studied. The lining structure is assumed to be arbitrary shape. Separating variable method of Helmholtz equations leads to the semi-analytical solutions of the potentials. By using the conformal mapping method, the lining structures of arbitrary shape can be mapped to the cirque at the same centre with different radii. The elastic and slip material constants of interface are introduced to analyze the effect of interfacial properties. The dynamic stress and pore pressure are solved by applying the displacement and stress boundary conditions with interface effect. In numerical examples, the dynamic stress and pore pressure under different interface coefficients (normal and circumferential spring coefficients and slip coefficient) are analyzed. It is found that the effect of normal spring coefficient is larger than that of circumferential spring coefficients. The imperfect interface effect on the dynamic stress and pore pressure is also related with the wave frequencies.

Three new pterocarpans, named abrusprecatins A-C (1–3), along with three known ones, namely medicarpin (4), maackiain (5), and 4-hydroxy-3-methoxy-8,9-methylenedioxypterocarpan (6) were isolated from the aerial parts of Abrus precatorius. The structures of these compounds were established by extensive analysis of mass spectrometric data, 1 D and 2 D NMR spectroscopic data. In addition, the absolute configurations were determined by a combination of single crystal X-ray diffraction analysis and circular dichroism spectroscopy.

A phytochemical investigation on the leaves of Callistemon viminalis resulted in the isolation of two unusual compounds, callistemonols A (1) and B (2). Callistemonol A (1) possesses a novel skeleton of a furan ring fusing both an α,β-triketone and a phloroglucinol unit, while callistemonol B (2) is an acylphloroglucinol derivative featuring two methyl substituents on a five-membered ring and an isovaleryl side chain. Their structures were fully characterized on the basis of extensive spectroscopic analysis, including 1D and 2D NMR parameters, as well as the IR and HRESIMS data. Callistemonol A (1) represents an example of a natural dibenzofuran with two phenyl moieties, and a plausible biogenetic pathway to generate this novel dibenzofuran through a C-C bond-forming radical SAM enzyme is proposed. Moreover, antimicrobial assays, in conjunction with time-killing and biophysical studies, revealed that 1 and 2 exert potent bactericidal activities against a panel of methicillin-resistant pathogenic microbes.

An elastic–slip interface model is proposed to investigate the effective elastic modulus of elliptical-fiber reinforced asphalt concrete, and the nonlinear factor related with the second-order term of strain is used to consider the large deformation of asphalt concrete. The representative volume element with effective isotropic medium is introduced to describe the overall properties of elliptical-fiber reinforced asphalt concrete. Combining the conformal mapping technique and polynomial function expanded method, a closed form solution of effective elastic modulus is obtained. Through numerical examples, the effects of interface material coefficients and the nonlinear factor on the effective elastic modulus under different shapes of fibers are discussed in detail. To validate the present interface model, experimental investigation on the interface effect on the elastic modulus is presented.

To avoid the in-service crack growth of pipelines, a fundamentally based mathematical model of a partially debonded pipeline embedded in the rock mass is proposed, and the dynamic crack open displacement under anti-plane shear waves is theoretical derived. The debonding region around the pipeline is modeled as an interface crack with noncontacting faces. The wave fields in different regions are expressed by wave function expansion method. The crack opening displacement in the debonding region is represented by Chebyshev polynomials. Some examples are illustrated, and the results are figured. The results show that the crack open displacement increases with increasing wave frequency. Due to the increase of pipeline thickness, the crack open displacement also increases. In the region of high frequency, the value of crack open displacement is more sensitive to the crack size. Comparison with existing results is given to validate this dynamic model.

Rosanortriterpenes A–B (RTA and RTB), two nortriterpenoids, are characteristic constituents in the fruits of Rosa laevigata var. leiocapus. However, pharmacological studies on these compounds are still scarce. In the present study, we aim to investigate the anti-inflammatory mechanisms associated with the effects of RTA–B in RAW264.7 macrophages and LO2 cells by detecting cell viabilities, nitric oxide (NO) production, tumour necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6) production. Simultaneously, the anti-inflammatory action mechanisms of these two compounds were illustrated through western blot assay. Besides, the antihepatic fibrosis activities of these compounds have also been explored. The results demonstrated that RTA and RTB inhibited the production of NO, TNF-α, and IL-6 and suppressed liver fibrosis. RTA and RTB treatment also greatly inhibited the activation of NF-kappaB (NF-κB) pathway. Our study confirmed the promising anti-inflammatory and anti-liver fibrosis actions of RTA–B, suggesting that they might be developed as alternative and promising drugs for the treatment of hepatic inflammatory and fibrotic diseases.

Rosanortriterpenes A–B (RTA and RTB), two nortriterpenoids, are characteristic constituents in the fruits of Rosa laevigata var. leiocapus. However, pharmacological studies on these compounds are still scarce. In the present study, we aim to investigate the anti-inflammatory mechanisms associated with the effects of RTA–B in RAW264.7 macrophages and LO2 cells by detecting cell viabilities, nitric oxide (NO) production, tumour necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6) production. Simultaneously, the anti-inflammatory action mechanisms of these two compounds were illustrated through western blot assay. Besides, the antihepatic fibrosis activities of these compounds have also been explored. The results demonstrated that RTA and RTB inhibited the production of NO, TNF-α, and IL-6 and suppressed liver fibrosis. RTA and RTB treatment also greatly inhibited the activation of NF-kappaB (NF-κB) pathway. Our study confirmed the promising anti-inflammatory and anti-liver fibrosis actions of RTA–B, suggesting that they might be developed as alternative and promising drugs for the treatment of hepatic inflammatory and fibrotic diseases.

A fundamentally based mathematical model of a partially corroded pipeline in a saturated poroelastic medium is presented, and the dynamic interaction around the pipeline under plane waves is derived. Based on Biot's poroelastic theory, the dynamic governing equations of the saturated poroelastic medium are decomposed. The wave fields around the corroded pipeline are expanded by using the wave function expansion method. The loose poroelastic medium in the corroded areas is simulated by the spring-type medium, and the thickness of pipeline is small. By introducing the different boundary conditions in the corroded and perfect areas, the expanded coefficients are solved. Through numerical examples, the jump of dynamic stress resulting from the corroded area under different wave frequencies is examined in detail.

Over the years, plant-derived substances have been developed as effective substitutes for synthetic insecticides because of their safety and environmental friendliness. In this study, we investigated the insecticidal properties of four polyacetylenes isolated from Bidens pilosa, a traditional edible herb, against Plutella xylostella (L.), Spodoptera litura, Mythimna separata (Walker), Spodoptera exigua (Hubner), Helicoverpa armigera and Ostrinia furnacalis (Guene’e). The polyacetylenes 1-4 showed potent insecticidal activities with LD50 values ranging from 0.133 to 4.084 μg/larva in the contact toxicity assay and with LC50 values ranging from 0.070 to 2.561 mg/mL in the stomach toxicity assay. Among these four compounds, compound 1 exhibited the highest insecticidal activity, comparable with the activity of commercial pesticide pyrethrins. The results of in vitro glutathione S-transferases (GSTs) and acetylcholinesterase (AChE) assays indicated these polyacetylenes exerted inhibitory effects on GSTs or (and) AChE in P. xylostella. Meanwhile, their anti-inflammatory properties were investigated using the q-PCR assay. These compounds proved to be non-cytotoxic against human keratinocytes (HaCaT) in MTT assay. These findings suggested that compounds 1-4 have the potential to be developed as skin-safe insecticidal agents.

One new ent-kaurane diterpene derivative (1), along with four known diterpenes, was isolated from the stems of Eurya chinensis R.Br. The structure of the new compound was established by extensive analysis of mass spectrometric and 1D and 2D NMR spectroscopic data. Compound 1 showed moderate anti-inflammatory activities with IC50 value of 8.12 μM. This is the first example of diterpenoids with 4-hydroxy-4-(2-hydroxyethyl)-1-hydroxyl-cyclohexanoyl substituent.

Methicillin-resistant Staphylococcus aureus (MRSA) poses a serious threat to global public health, because it exhibits resistance to existing antibiotics and therefore high rates of morbidity and mortality. In this study, twenty-one natural product-based acylphloroglucinol congeners were synthesized, which possessed different side chains. Antibacterial screening against MRSA strains revealed that acyl moiety tailoring is a prerequisite for the antibacterial activity. Moreover, the lipophilicity, rather than the magnitude of the hydrophobic acyl tail dominates variability in activity potency. Compound 11j was identified as a promising lead for the generation of new anti-MRSA drug development. It was discovered by optimization of the side chain length in light of the potency, the breadth of the antibacterial spectrum, the rate of bactericidal action, as well as the membrane selectivity. Compound 11j exerted profound in vitro antibacterial activity against the MRSA strain (JCSC 2172), and its MIC was 3-4 orders of magnitude lower than that of vancomycin. A preliminary mode of action study of compound 11j at the biophysical and morphology levels disclosed that the mechanism underlying its anti-MRSA activity included membrane depolarization and, to a lesser extent, membrane disruption and cell lysis.

One new oleanane-type nortriterpene, rosanortriterpene A (

Three new pterocarpans, named abrusprecatins A-C (

A phytochemical investigation on the leaves of

In engineering construction, the elastic-slip interface often exists around the tunnel. An elastic-slip interface model is proposed to analyze the dynamic response of underwater convey tunnel, and the surrounding soil is assumed to be saturated poroelastic medium. The reflected, refracted and scattered waves in the free surface water, the surrounding soil medium and the tunnel are expressed by wave function expansion method. Based on Biot’s dynamic theory, an elastic-slip interface is developed to analyze the scattering of P and SV waves around the tunnel. The interface coefficients (normal and tangential spring coefficients and slip coefficient) are introduced to analyze the elastic-slip interface effect on the dynamic stresses under different wave frequencies. It can be concluded that the effect of normal spring coefficient is greater than that of tangential spring coefficients. The interface effect in the region of low frequency is greater than that of high frequency. The interface effect under different surface water depths and embedded depths of tunnel is also examined. Comparison with existing numerical results validates this dynamic model.

Blasting excavation of deep-buried structures is a complex dynamic process which can cause blast loading and insitu stress redistribution. An elastic-slip interface model is introduced to analyze the dynamic response of twin tunnels subjected to blast waves. The blast waves is expressed by Fourier-Bessel expansion method of wave function, and the wave field is superimposed by Graf coordinate transformation method. To analyze the interface effect, the elastic and slip coefficients of interface are introduced to describe the interface properties. Through numerical examples, it is found that the dynamic stress at the upper points of tunnels is larger than that at the sides of tunnels. However, the interface effect on the dynamic stress at the sides of tunnels is larger than that at the upper points, especially a small distance between twin tunnels is selected. Due to the interface effect, not only compressive but also tensile deformations can be seen, and the large oscillation of dynamic stress at the sides of tunnels can be observed. Excellent agreement with existing numerical results validates this dynamic model.

Longistylin A (LLA) is an abundant stilbene isolated from the leaves of Cajanus cajan (L.) Millsp. However, the antibacterial effect of LLA is not yet understood. Therefore, in this study, a detailed investigation of the antibacterial effect of LLA, particularly against methicillin-resistant Staphylococcus aureus (MRSA), was conducted. In vitro, LLA exhibited strong antibacterial activity against MRSA with a minimum inhibitory concentration (MIC) of 1.56 µg/mL and displayed much more rapid bactericidal activity (3-log decrease in MRSA survival within 8 h) than vancomycin. A membrane-targeting experiment suggested that the antibacterial activity of LLA is associated with perturbation of the bacterial membrane potential and increased membrane permeability. Notably, LLA had relatively weak cytotoxicity to murine macrophages [50% cytotoxic concentration (CC50) = 8.61 ± 0.57 µg/mL]. In vivo, topical treatment of a skin injury with LLA improved wound healing and closure in an MRSA-infected wound healing mouse model. After 3 days treatment, LLA decreased MRSA bacterial counts in the wounded region, reduced the accumulation of immune cells at the injury site, and alleviated induction of the inflammatory cytokines tumour necrosis factor-alpha (180.74 ± 10.78 pg/mL vs. 606.57 ± 68.99 pg/mL) and interleukin-6 (87.25 ± 10.19 pg/mL vs. 280.58 ± 42.27 pg/mL) in serum.

We have reported that SIAH1 is down-regulated and associated with apoptosis and invasion in human breast cancer. However, the molecular mechanisms leading to SIAH1 down-regulation remain to be elucidated. Here, we demonstrated that miR-107 directly down-regulates SIAH1 expression in human breast cancer cells. Over- expression of miR-107 reduced SIAH1 expression, promoted human breast cancer cell proliferation, colony formation, migration and invasion, and inhibited apoptosis. On the contrary, silencing of miR-107 increased SIAH1 expression and inhibited the tumor growth of MDA-MB-231 cells, a kind of triple-negative breast cancer (TNBC) cells, in vitro and in vivo. Our results reveal that miR-107 is an upstream regulator for SIAH1 down-regulation in human breast cancer cells and miR-107 provides a potential effective target for the treatment of TNBC.

Two new ent-kaurane diterpenes (1–2), together with five known analogs, were isolated from the stems of Eurya chinensis. The structures of new compounds were established by extensive analysis of mass spectrometric and 1D and 2D NMR spectroscopic data. Compound 3 exhibited noticeable anti-inflammatory activity as denoted by inhibiting LPS-induced nitric oxide (NO) production in RAW264.7 cells with an IC50 value of 7.82 μM. Compound 4 showed potent cytotoxic activity against human cancer cell lines NCI-H46, HepG2 and SW480 with IC50 values ranging from 7.45 to 8.54 μM.

Three new dimeric kavalactones, designated as diyangonins A–C (1–3), along with two known analogs were isolated from the roots of Piper methysticum. Their structures were elucidated by means of extensive analysis of their 1D, 2D NMR, and mass spectroscopic data. All these dimers possess a skeleton featuring a cyclobutane ring connecting two kavalactone units in head-to-tail or head-to-head mode. Compounds 1–5 were evaluated for their cytotoxic activities against human tumor cell lines.

The compound 29-(4-methylpiperazine)-luepol (M22), a novel derivative of lupeol has shown anti-proliferative effects against the human non-small cell lung cancer A549 cell line. M22 showed significant anti-proliferative activity at 6.80 μM and increased accumulation of G1 cells and effectively suppressed expression of the G1 arrest-related genes cyclins D1 and E1, CDK2 and CDC25A. This was further confirmed by Western blotting demonstrating decreased cyclin D1 and CDC25A protein levels. Furthermore, M22 caused induction of apoptosis that downregulated the anti-apoptotic BCL-2 gene and increased expression of BAX, CASP3 and CASP9 as well as the APAF1 gene. The effect of caspase-induced apoptosis was confirmed by an increase in reactive oxygen species (ROS), loss of mitochondrial membrane potential (MMP). Taken together, our findings indicated that M22 possessed potent anti-proliferative and apoptotic activities.

Three new kavalactone dimers, designated as yangonindimers A-C (1–3), along with one known analogue were isolated from the roots of Piper methysticum. Their structures were elucidated via extensive analysis of their 1D, 2D NMR and mass spectroscopic data. All these dimers possess a skeleton featuring a cyclobutane ring connecting two kavalactone units. Compounds 1–4 were evaluated for their cytotoxic activities against human tumour cell lines NCI-H46, SW480 and HepG2, but none showed significant activity.

Analysis method using orthogonal experimental design factor of four levels of three experiments, electroforming solution components were verified. On the current efficiency of the sample was calculated, its micro-hardness, tensile strength and stress were measured; and its XRD tests, analysis of the micro-strain, grain size and position electrical castings dislocation density. Four factors shows that the optimum level of nickel sulfate 350g / L, nickel chloride, 15g / L, the current density 3A/dm2, THF was 0.5g / L, saccharin was 0.4g / L.

Obtaining effective value points is one of key issues in cubic B-spline curve reconstruction. Since it is unfavorable for the selection of value points through curvature methods and the point cloud data acquired from ICT slice images is characterized with large volume of data, high noise and density, a baseline adaptive method is presented to get value points for curve reconstruction, baseline and scale threshold determined by wavelet multi-scale, in which the value points is obtained and curve is reconstructed automatically. Hausdorff distance is adopted to calculate the error of cubic B-spline curve reconstruction. Comparative analysis with existing methods proves that our method can effectively restrain noise and quickly reconstruct contour curves.

How to effectively extract contour dominant points is one of key problems in process of industrial CT image, second extraction method was put forward. Second extraction method included two steps: rough extraction and accurate extraction. Firstly, discrete circular curvatures of contour points are calculated. Secondly, through rough extraction step, bad points and points which arent correlated with contour features were removed. At last, through accurate extraction step, contour dominant points were extracted by levels of detail. Experimental results show that contour dominant points can describe contours shape and redundant data are removed, the proposed method is simple and efficient.

Through considering the symmetry constraint characteristics in mechanical product contours, an auto-identification method of two-dimensional symmetrical contour based on feature matching is presented in this paper. Firstly, the feature points are extracted based on contour cloud point data partition and by using offset method, the different distribution rules of axis-symmetrical and rotation-symmetrical images for judging the type of symmetry was studied. The feature description parameters of symmetrical contour were calculated by adopting rotational inertia method and periodic method, which is regarded as the parameters for solving overall constraint optimization of the contour. Examples show that the proposed method can effectively identify the symmetrical contours and their types, and accurately extract the symmetrical constraint features.

A facile and efficient synthesis of indole has been developed using ketones or cyclohexandiones with aryhydrazine hydrochlorides in 85% to 95% yields in water under ultrasound irradiation in the presence of Novel SO3H-functionalized ionic liquids (ILs) catalyst. Simple work-up procedure, environmentally friendly, inexpensive and non-toxic catalyst, shorter reaction times along with excellent product yields are the significant features of this practical method.

Novel SO 3 H-functionalized ionic liquids were successfully applied as catalysts for one-pot Fischer indole synthesis under microwave irradiation and in a water medium. Various types of indoles were prepared using single-carbonyl ketones/aldehydes or cyclohexandiones with aryhydrazine hydrochlorides in 86–96% yields in water under microwave irradiation. The indole products could be conveniently separated from the reaction mixture through filtration, and the catalytic system of [(HSO 3 -p) 2 im][CF 3 SO 3 ]/H 2 O could be reused directly without any treatment. The entire process is simple, time saving, and environmentally friendly.

Novel SO3H-functionalized ionic liquids were successfully applied as catalysts for the one-pot three component Biginelli condensation under ultrasound irradiation without solvent. Various types of 3,4-dihydorpymidine(1H)-(thio)-ones were provided in 84-98% yields and conveniently separated from the reaction mixture by filtration, the dissolved catalyst could be reused with simple treatment. This novel synthetic method is especially favoured because it provides a synergy between ionic liquids and ultrasound irradiation which offers the advantages of high yields, short reaction times, simplicity, and easy workup compared to the conventional methods reported in the literature

Novel SO3H-functionalized ionic liquids were successfully applied as catalysts for synthesis of xanthenediones under microwave irradiation in Aqueous. Various types of Xanthenes were provided in 90-97% yields using the catalytic system of [(HSO3-p)2im][CF3SO3]/H2O. The products could be conveniently separated from the reaction mixture by filtration and the dissolved catalyst could be reused without any treatment, which of the separation process was performed in water without using any organic solvents. The method not only has the adventages of shrot time and simple operation, but also is environmentally friendly.

Position-limit protection equipment is the major control equipment on CNC machine, whose logic control method is the assurance of normal work of position-limit protection equipments. It will reduce the effect of position-limit protection or cause it malfunction, if we apply the logical control method not suitably. Current CNC machines are provided with a positive control limitation protection device, and then it is likely to happen malfunction even cause accidents due to its electric circuit errors or its open circuit. In order to solve this shortcoming, somebody has worked out a new method, which is called negative logic control. This paper introduces the new logic control method’s basic principle and its practical usage.

Interplay between integrins and extracellular matrix is suggested to play an important role in malignant progression and tumor differentiation. The aim of the study was to determine the combined expression of integrin β3 and tenascin-c (TN-c) in breast cancer and examine whether integrin β3 and TN-c can activate urokinase-type plasminogen activator (uPA) through p38 mitogen-activated protein kinase (p38 MAPK). We detected the expression of integrin β3, TN-c, p-p38, and uPA in 80 cases of breast invasive ductal carcinoma by immunohistochemistry. In addition, we blocked integrin β3 and TN-c in the MDA-MB-231 breast cancer cells and detected the expression of p-p38 and uPA by Western blot. Integrin β3, TN-c, p-p38, and uPA showed high levels of expression in breast invasive ductal carcinoma. The expression of integrin β3, TN-c, and uPA was correlated with lymph node metastasis and TNM stage in breast cancer. Furthermore, correlations were noted between any two of the three proteins. The expression of p-p38 and uPA decreased in MDA-MB-231 cells after the addition of integrin β3 antibody and TN-c antibody. The expression of uPA decreased after addition of SB203580. Our results demonstrate that inhibition of the expression of integrin β3 and TN-c could decrease the expression of uPA through p38 MAPK in breast cancer, suggesting that the interaction between integrin β3 and TN-c serves an important role in breast cancer.

Sonic Hedgehog (Shh) plays an essential role in vertebrate organogenesis as well as the development of some cancers, including breast cancer. The aim of the present study was to characterize more precisely its role in breast carcinogenesis and elucidate its regulation mechanisms. The expression of Shh was investigated in 97 breast carcinomas and 22 paired non-tumorous tissues (distant from the primary tumor) by immunohistochemistry and in four breast cell lines by Western blotting. We also analyzed the methylation status of the Shh gene with methylation-specific PCR and assessed whether nuclear factor-kappa B (NF-kappaB) and Gli1 were expressed in breast tissues by immunohistochemistry. Our results showed that Shh protein expression in breast carcinomas was significant higher than that in normal breast tissues (P < 0.01). The up-regulation of Shh in breast carcinomas was correlated significantly with early clinical stage (P < 0.05). In addition, we found a substantial increase in Shh expression at both the mRNA and protein levels in several human breast carcinoma cell lines. The expression level of nuclear Gli1 was positively associated with the expression level of Shh in breast tissues (P < 0.001). Promoter region hypomethylation (43/61, 70.5%) was frequently observed in breast carcinomas and significantly associated with Shh up-regulation (P < 0.05). The DNA methyltransferase inhibitor 5-azacytidine (5-Aza) reduced the methylation of Shh promoter and increased the expression of Shh protein in MDA-MB-435 and MCF-10A cells. Furthermore, most of the breast carcinoma cases with Shh up-regulation had increased expression of NF-kappaB (35/49, 71.4%; P < 0.001). Taken together, these observations suggest that Shh overexpression is a critical event in breast carcinogenesis, and Shh promoter hypomethylation and NF-kappaB up-regulation are responsible for the up-regulation of Shh.

Seven in absentia homolog1 (SIAH1) was reported as a tumor suppressor and played an important role in regulating cell apoptosis. However, its effects on the breast carcinogenesis remain unclear. In this study, our aims were to examine the relationship between SIAH1 and Bcl-2-interacting mediator of cell death (Bim) and to explore the effects of SIAH1 on the breast carcinogenesis. Immunohistochemical analysis in 231 cases of breast tissues showed that the expression of SIAH1 and Bim were significantly decreased in the breast carcinogenesis. Moreover, SIAH1 expression was significantly correlated with Bim. Both SIAH1 and Bim expression were significantly higher in well to moderately differentiated and in early-stage breast cancer. Reverse transcription (RT)-polymerase chain reaction (PCR) and Western blot analysis in paired breast cancer tissues and breast cell lines found that the expression of SIAH1 was lower in the breast cancer tissues and cell lines. SIAH1 inducing apoptosis of the breast cancer cells was dependent on Bim. However, SIAH1 inhibiting invasion of the breast cancer cells was independent of Bim. The increase of the function of SIAH1 to upregulate the expression of Bim may play an important role in the progression of breast cancer. Restoration of the function of SIAH1 may be a new therapeutic target of human breast cancer. © 2010 Wiley-Liss, Inc.

Seven in absentia homolog 1 (SIAH1), a homologue of Drosophila seven in absentia (Sina), has emerged as a tumor suppressor and plays an important role in regulating cell apoptosis. To investigate the role and possible mechanism of SIAH1 in breast cancer cells, we up-regulated the expression of SIAH1 using pcDNA3-myc-SIAH1 and knocked down SIAH1 using SIAH1 siRNA. We found that the overexpression of SIAH1 induced cell apoptosis by up-regulating the level of Bim through the activation of the JNK signaling pathway, and the suppression of SIAH1 expression increased cell invasion via the activation of the ERK signaling pathway in breast cancer cells. All these results indicate that the JNK and ERK signaling pathways may play an important role in the SIAH1-dependent biological behavior of breast cancer, and it may be a good molecular therapeutic target to increase the expression level of SIAH1 through promoting cell apoptosis and inhibiting cell invasion in human breast cancer.

The spring-mass-capacitor structure in micro-electro-mechanical systems (MEMS) is a typical macromodel, its response and stability under step voltage is presented in this paper. Energy method is used to analyze the dynamic behavior of mass block where its velocity is zero and accelerometer is zero, respectively. The condition of stability under step voltage is the initial stiffness ratio must less than 0.25, and finally the relation of energy loss and oscillating behavior of block is analyzed. The conclusion is useful to analyze the response of structure and helpful to design a MEMS system composing of spring-mass-capacitor structure.