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Find video protocols related to scientific articles indexed in Pubmed.
Cobalt nanoparticles embedded in N-doped carbon as an efficient bifunctional electrocatalyst for oxygen reduction and evolution reactions.
Nanoscale
PUBLISHED: 11-05-2014
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Cobalt based catalysts are promising bifunctional electrocatalysts for both oxygen reduction and oxygen evolution reactions (ORR and OER) in unitized regenerative fuel cells (URFCs) operating with alkaline electrolytes. Here we report a hybrid composite of cobalt nanoparticles embedded in nitrogen-doped carbon (Co/N-C) via a solvothermal carbonization strategy. With the synergistic effect arising from the N-doped carbon and cobalt nanoparticles in the composite, the Co/N-C hybrid catalyst exhibits highly efficient bifunctional catalytic activity and excellent stability toward both ORR and OER. The ?E (oxygen electrode activity parameter for judging the overall electrocatalytic activity of a bifunctional electrocatalyst) value for Co/N-C is 0.859 V, which is smaller than those of Pt/C and most of the non-precious metal catalysts in previous studies. Furthermore, the Co/N-C composite also shows better bifunctional catalytic activity than its oxidative counterparts, which could be attributed to the high specific surface area and the efficient charge transfer ability of the composite, as well as the good synergistic effect between N-doped carbon and the Co nanoparticles in the Co/N-C composite.
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N-acetyl-seryl-aspartyl-lysyl-proline reduces cardiac collagen cross-linking and inflammation in angiotensin II-induced hypertensive rats.
Clin. Sci.
PUBLISHED: 10-28-2014
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We have reported previously that Ac-SDKP (N-acetyl-seryl-aspartyl-lysyl-proline) reduces fibrosis and inflammation (in macrophages and mast cells). However, it is not known whether Ac-SDKP decreases collagen cross-linking and lymphocyte infiltration; lymphocytes modulate both collagen cross-linking and ECM (extracellular matrix) formation in hypertension. Thus we hypothesized that (i) in AngII (angiotensin II)-induced hypertension, Ac-SDKP prevents increases in cross-linked and total collagen by down-regulating LOX (lysyl oxidase), the enzyme responsible for cross-linking, and (ii) these effects are associated with decreased pro-fibrotic cytokine TGF? (transforming growth factor ?) and the pro-inflammatory transcription factor NF-?B (nuclear factor ?B) and CD4+/CD8+ lymphocyte infiltration. We induced hypertension in rats by infusing AngII either alone or combined with Ac-SDKP for 3 weeks. Whereas Ac-SDKP failed to lower BP (blood pressure) or LV (left ventricular) hypertrophy, it did prevent AngII-induced increases in (i) cross-linked and total collagen, (ii) LOX mRNA expression and LOXL1 (LOX-like 1) protein, (iii) TGF? expression, (iv) nuclear translocation of NF-?B, (v) CD4+/CD8+ lymphocyte infiltration, and (vi) CD68+ macrophages infiltration. In addition, we found a positive correlation between CD4+ infiltration and LOXL1 expression. In conclusion, the effect of Ac-SDKP on collagen cross-linking and total collagen may be due to reduced TGF?1, LOXL1, and lymphocyte and macrophage infiltration, and its effect on inflammation could be due to lower NF-?B.
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Deletion of interleukin-6 prevents cardiac inflammation, fibrosis and dysfunction without affecting blood pressure in angiotensin II-high salt-induced hypertension.
J. Hypertens.
PUBLISHED: 10-12-2014
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Inflammation has been proposed as a key component in the development of hypertension and cardiac remodeling associated with different cardiovascular diseases. However, the role of the proinflammatory cytokine interleukin-6 in the chronic stage of hypertension is not well defined. Here, we tested the hypothesis that deletion of interleukin-6 protects against the development of hypertension, cardiac inflammation, fibrosis, remodeling and dysfunction induced by high salt diet and angiotensin II (Ang II).
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Screening Medicinal Plants for Use against Dactylogyrus intermedius (Monogenea) Infection in Goldfish.
J. Aquat. Anim. Health
PUBLISHED: 09-18-2014
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Abstract Methanol extracts of 24 traditional medicinal plants with potential anthelmintic activity against Dactylogyrus intermedius (Monogenea) in Goldfish Carassius auratus were investigated. Abrus cantoniensis, Citrus medica, Dioscorea collettii, and Polygonum multiflorum exhibited 100% activity and were selected for further evaluation by applying five solvents (petroleum ether, chloroform, ethyl acetate, methanol, and water) for the extraction of the samples, followed by an in vivo bioassay. Among the plants tested, water, methanol, and ethyl-acetate extracts of P. multiflorum showed the highest efficacies; EC50 values (median concentration that results in 50% of its maximal effect) were 1.9, 5.4, and 9.1 mg/L, respectively, and extracts showed 100% efficacy against Dactylogyrus intermedius at 100, 12.5, and 25 mg/L. This was followed by ethyl-acetate, chloroform, and methanol extracts of Dioscorea collettii, which demonstrated 100% efficacy at 80, 80, and 120 mg/L and had EC50 values of 19.7, 27.1, and 37.8 mg/L, respectively, after 48 h of exposure. Chloroform and ethyl-acetate extracts of C. medica, which exhibited 100% efficacy against Dactylogyrus intermedius at 100 and 125 mg/L, revealed similar activity and had EC50 values of 58.7 and 51.3 mg/L, respectively. The ethyl-acetate and methanol extracts of A. cantoniensis exhibited the lowest activity and had EC50 values of 279.4 and 64.3 mg/L. Acute toxicities of these active extracts were investigated on Goldfish for 48 h. The findings indicated that extracts of the four plants can be developed as a preferred natural antiparasitic for the control of D. intermedius. Received June 15, 2013; accepted February 11, 2014.
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Seasonal migration of Apolygus lucorum (Hemiptera: Miridae) over the Bohai Sea in northern China.
J. Econ. Entomol.
PUBLISHED: 09-09-2014
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During the past decade, Apolygus lucorum (Meyer-Dür) has become a key pest on cotton in northern China. Whether or not this species is a migrant, and if so, what pattern of seasonal migration this species exhibits remains unknown. The combination of searchlight trapping and radar observation on an isolated island in the center of Bohai Gulf during the past 11 yr provided direct evidence that both male and female A. lucorum adults migrate at least 40-60 km (and probably much greater distances) across the Bohai Gulf waters. There were considerable yearly and monthly variation in the number of A. lucorum trapped on BH, and the migration period during 2009-2013 ranged from 102 to 154 d. A. lucorum adults had downwind displacement rather than randomly by heading toward their seasonally favorable directions, which toward the east-northeast in summer, but south-southwest (SSW) in early autumn. The vast majority of adults flying at airspeeds 0.5-2.5 m/s and at altitudes < 150 m above ground level. Most of trapped females were virgins with little or no ovarian development, as suggests that the onset of migration is initiated mainly by sexually immature individuals, which is termed the "oogenesis-flight syndrome." Such findings reveal a new route for A. lucorum movements northward to and southward from the northeastern agricultural region of China, which will help us develop more effective management strategies against this pest species.
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Regioselective C?H Imidation of Five-Membered Heterocyclic Compounds through a Metal Catalytic or Organocatalytic Approach.
Chem Asian J
PUBLISHED: 09-08-2014
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An efficient method for the synthesis of 2-amino and ?-amino five-membered heterocyclic derivatives that are closely related to a variety of biologically active natural products is described. Regioselectivity was achieved through a metal catalytic or organocatalytic approach. Preliminary studies on the reaction mechanism suggest a radical imidation pathway; however, further studies are needed to verify the mechanism.
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The end of a myth-Bt (Cry1Ab) maize does not harm green lacewings.
Front Plant Sci
PUBLISHED: 08-12-2014
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A concern with Bt-transgenic insect-resistant plants is their potential to harm non-target organisms. Early studies reported that Cry1Ab-producing Bt maize and purified Cry1Ab harmed larvae of the green lacewing, Chrysoperla carnea. Although these effects could not be confirmed in subsequent studies, some authors still refer to them as evidence that Bt maize harms beneficial species. We provide a comprehensive review of the studies evaluating the effects of Bt (Cry1Ab) maize on C. carnea. The evidence indicates that this important predator is not affected by Bt maize or by the produced Cry1Ab protein. We discuss how conceptual models can assist environmental risk assessments, and we emphasize the importance of robust and reproducible studies.
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Acquisition of Cry1Ac protein by non-target arthropods in Bt soybean fields.
PLoS ONE
PUBLISHED: 08-11-2014
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Soybean tissue and arthropods were collected in Bt soybean fields in China at different times during the growing season to investigate the exposure of arthropods to the plant-produced Cry1Ac toxin and the transmission of the toxin within the food web. Samples from 52 arthropod species/taxa belonging to 42 families in 10 orders were analysed for their Cry1Ac content using enzyme-linked immunosorbent assay (ELISA). Among the 22 species/taxa for which three samples were analysed, toxin concentration was highest in the grasshopper Atractomorpha sinensis and represented about 50% of the concentration in soybean leaves. Other species/taxa did not contain detectable toxin or contained a concentration that was between 1 and 10% of that detected in leaves. These Cry1Ac-positive arthropods included a number of mesophyll-feeding Hemiptera, a cicadellid, a curculionid beetle and, among the predators, a thomisid spider and an unidentified predatory bug belonging to the Anthocoridae. Within an arthropod species/taxon, the Cry1Ac content sometimes varied between life stages (nymphs/larvae vs. adults) and sampling dates (before, during, and after flowering). Our study is the first to provide information on Cry1Ac-expression levels in soybean plants and Cry1Ac concentrations in non-target arthropods in Chinese soybean fields. The data will be useful for assessing the risk of non-target arthropod exposure to Cry1Ac in soybean.
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Does Athetis lepigone moth (Lepidoptera: Noctuidae) take a long-distance migration?
J. Econ. Entomol.
PUBLISHED: 07-17-2014
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Athetis lepigone (Möschler), a new lepidopteran pest in China, has spread quickly to seven provinces since it was first reported causing damage on summer maize in Hebei province in 2005, Whether this species is a migrant or not remains unknown. The past 3 yr searchlight trapping on an island in the center of Bohai Gulf provided direct evidence that both male and female A. lepigone moths migrate across the Bohai Gulf waters in northern China because no host crops or A. lepigone larvae were found on this island. The four migration waves observed in this study represent high-altitude movements of the overwintering, first, second, and third generations of A. lepigone moths, respectively. Carbon isotope analysis showed that 1.76-5.44% of the tested A. lepigone moths originated from C4 plants, which provides additional evidence that this species is a migrant because there are no C4 plants on this small island. The 89.24-96.89% of tested A. lepigone moths originated from C3 plants were significantly higher than that from C4 plants in all generations, suggesting that maize fields are not the main host sites for A. lepigone. Few females were trapped in spring and early summer with relatively high mating frequency and more advanced ovarian development, suggesting that the migration of this species is not completely bound by the "oogenesis-flight syndrome." These findings reveal a new route for A. lepigone migrating to and from the northeastern agricultural region of China, and improve our knowledge of the migration ecology of A. lepigone. Further studies are needed to clarify the migration trajectories that will help in developing sound forecasting systems for this pest species.
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Isolation, culture and phenotypic characterization of human sweat gland epithelial cells.
Int. J. Mol. Med.
PUBLISHED: 07-14-2014
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Sweat gland epithelial cells (SGECs) have been identified as essential for the regeneration of sweat glands and for the construction of skin substitutes containing skin appendages. Consequently, the isolation, culture and phenotypic characterization of SGECs are of paramount importance. In the present study study, human sweat glands were isolated by pipetting under a phase contrast microscope following digestion with collagenase type I. Subsequently, a microscopic organ culture technique was used for the primary culture of human SGECs, and the culture conditions were modified in order to achieve optimal cell growth status. Primary SGECs were identified based on their expression of markers specific for sweat glands, including carcinoembryonic antigen (CEA), CK7, CK8, CK14, CK15, CK18 and CK19. We explored the possible presence of stem cells in human sweat glands by detecting their expression of leucine-rich repeat-containing G protein-coupled receptor 5 (LGR5). Primary SGECs achieved a good growth state when cultured under serum-free conditions. After one passage, the cells cultured in keratinocyte serum-free medium with 1% fetal bovine serum (FBS) still showed a prominent proliferative activity. Phenotypic analysis by immunofluorescence microscopy, reverse transcription-polymerase chain reaction (RT-PCR), and western blot analysis demonstrated the expression of sweat gland-specific markers, including CEA, CK7, CK8, CK14, CK15, CK18 and CK19. In addition, RT-PCR and immunochemistry detected the expression of LGR5. In comparison with traditional serum-containing conditions, serum-free culture provides the preferred culture conditions for human SGECs. LGR5 is a novel marker that identifies human sweat gland-derived stem cells.
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Inhibition of allergic airway inflammation through the blockage of NF-?B activation by ellagic acid in an ovalbumin-induced mouse asthma model.
Food Funct
PUBLISHED: 07-08-2014
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Allergic asthma is a complex inflammatory disease characterized by airway hyperresponsiveness, eosinophilic inflammation and the hypersecretion of mucus by goblet cells. Ellagic acid (EA), a natural polyphenolic compound present as ellagitannins in fruits and fruit juices, has been reported to show potent anti-inflammatory properties in various diseases. We aimed to investigate the effects of EA in an ovalbumin (OVA)-induced mouse asthma model and to explore its potential mechanism of action. Our results showed that EA resulted in a significant reduction in lung eosinophilia, increased Th2 cytokines in bronchoalveolar lavage fluid and increased OVA-induced specific IgE in serum samples. Moreover, histological examination showed that EA markedly inhibited lung eosinophilic inflammation and goblet cell hyperplasia. In addition, EA attenuated the development of airway hyperresponsiveness and blocked NF-?B activation. These results demonstrate that EA shows obvious anti-inflammatory effects in OVA-induced asthma in a mouse model, possibly through inhibiting NF-?B activation. Therefore it may be a potential therapeutic agent for the treatment of allergic asthma.
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Metallic conductivity transition of carbon nanotube yarns coated with silver particles.
Nanotechnology
PUBLISHED: 06-24-2014
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Dry spun carbon nanotube yarns made from vertically aligned multiwalled carbon nanotube forests possess high mechanical strength and behave like semiconductors with electrical conductivity of the order of 4 × 10(4) S m(-1). Coating a submicron-thick film of silver particle-filled polymer on the surface increased the electrical conductivity of the carbon nanotube yarn by 60-fold without significantly sacrificing its mechanical strength. The transitional characteristics of the silver-coated carbon nanotube yarn were investigated by varying the take-up ratio of the silver coating. A step change in conductivity was observed when the silver content in the coated yarn was between 7 and 10 wt% as a result of the formation of connected silver particle networks on the carbon nanotube yarn surface.
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Arthropod abundance and diversity in transgenic bt soybean.
Environ. Entomol.
PUBLISHED: 06-09-2014
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Before the commercialization of any insect-resistant genetically modified crop, it must be subjected to a rigorous premarket risk assessment. Here, possible effects of growing of transgenic Cry1Ac soybean on arthropod communities under field conditions were assessed for 2 yr and quantified in terms of arthropod community indices including the Shannon-Weaver diversity index, richness index, and dominance index. Our results showed no significant differences of diversity, richness, or dominant indices for Bt soybean compared with the recipient cultivar, conventional soybean, or sprayed conventional soybean. Conventional soybean treatment with insecticide had an adverse effect on the arthropod community after spraying, but arthropod community diversity recovered quickly. Bt soybean had no negative effect on the dominant distribution of subcommunities, including sucking pests, other pests, predators, parasitoids, and others except for lepidopteran pests. The dominance distribution of lepidopteran pests decreased significantly in Bt soybean because of the significant decrease in the numbers of Spodoptera litura (F.) and Ascotis selenaria Schiffermüller et Denis compared with the recipient cultivar. Our results showed that there were no negative effects of Cry1Ac soybean on the arthropod community in soybean field plots in the short term.
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Caveolin-1 expression in different types of psoriatic lesions: analysis of 66 cases.
Indian J Dermatol
PUBLISHED: 06-04-2014
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Caveolin-1 is a key structural and functional protein. Caveolin-1 is known to modulate multiple signal-transducing pathways involved in cell differentiation and proliferation. Psoriasis is viewed as a multifactorial pathology characterized by keratinocyte hyperproliferation and abnormal cell maturation.
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Exchange-Coupled fct-FePd/?-Fe Nanocomposite Magnets Converted from Pd/Fe3 O4 Core/Shell Nanoparticles.
Chemistry
PUBLISHED: 06-02-2014
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We report the controlled synthesis of exchange-coupled face-centered tetragonal (fct) FePd/?-Fe nanocomposite magnets with variable Fe concentration. The composite was converted from Pd/Fe3 O4 core/shell nanoparticles through a high-temperature annealing process in a reducing atmosphere. The shell thickness of core/shell Pd/Fe3 O4 nanoparticles could be readily tuned, and subsequently the concentration of Fe in nanocomposite magnets was controlled. Upon annealing reduction, the hard magnetic fct-FePd phase was formed by the interdiffusion between reduced ?-Fe and face-centered cubic (fcc) Pd, whereas the excessive ?-Fe remained around the fct-FePd grains, realizing exchange coupling between the soft magnetic ?-Fe and hard magnetic fct-FePd phases. Magnetic measurements showed variation in the magnetic properties of the nanocomposite magnets with different compositions, indicating distinct exchange coupling at the interfaces. The coercivity of the exchange-coupled nanocomposites could be tuned from 0.7 to 2.8?kOe and the saturation magnetization could be controlled from 93 to 160?emu?g(-1) . This work provides a bottom-up approach using exchange-coupled nanocomposites for engineering advanced permanent magnets with controllable magnetic properties.
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Stevioside plays an anti-inflammatory role by regulating the NF-?B and MAPK pathways in S. aureus-infected mouse mammary glands.
Inflammation
PUBLISHED: 05-27-2014
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Mastitis is an inflammatory disease caused by microbial infection. Staphylococcus aureus is one of the primary bacteria responsible for mastitis. Stevioside is isolated from Stevia rebaudiana and is known to have therapeutic functions. This study was designed to evaluate the effects of stevioside in a mouse model of S. aureus-induced mastitis. In this study, the mouse mammary gland was infected with S. aureus to induce the mastitis model. The stevioside was administered intraperitoneally after the S. aureus infection was established. Hematoxylin-eosin (HE) staining, ELISA, Western blot, and q-PCR methods were used. The results show that stevioside significantly reduced the inflammatory cell infiltration and the levels of TNF-?, IL-1?, and IL-6 and the respective expression of their messenger RNAs (mRNAs). Further studies revealed that stevioside downregulated the TLR2, NF-?B, and (mitogen-activated protein kinase) MAPK signaling pathways in the S. aureus-infected mouse mammary gland. Our results demonstrate that stevioside reduced the expression of TNF-?, IL-1?, and IL-6 by inhibiting the phosphorylation of proteins in the NF-?B and MAPK signaling pathways dose-dependently, but that their mRNA expression was not obviously changed.
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Liver X receptor agonist prevents LPS-induced mastitis in mice.
Int. Immunopharmacol.
PUBLISHED: 05-26-2014
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Liver X receptor-? (LXR-?) which belongs to the nuclear receptor superfamily, is a ligand-activated transcription factor. Best known for its ability to regulate lipid metabolism and transport, LXRs have recently also been implicated in regulation of inflammatory response. The aim of this study was to investigate the preventive effects of synthetic LXR-? agonist T0901317 on LPS-induced mastitis in mice. The mouse model of mastitis was induced by injection of LPS through the duct of mammary gland. T0901317 was injected 1h before and 12h after induction of LPS intraperitoneally. The results showed that T0901317 significantly attenuated the infiltration of neutrophilic granulocytes, and the activation of myeloperoxidase (MPO); down-regulated the level of pro-inflammatory mediators including TNF-?, IL-1?, IL-6, COX-2 and PEG2; inhibited the phosphorylation of I?B-? and NF-?B p65, caused by LPS. Moreover, we report for the first time that LXR-? activation impaired LPS-induced mastitis. Taken together, these data indicated that T0901317 had protective effect on mastitis and the anti-inflammatory mechanism of T0901317 on LPS induced mastitis in mice may be due to its ability to inhibit NF-?B signaling pathway. LXR-? activation can be used as a therapeutic approach to treat mastitis.
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Survival analysis for valproic acid use in adult glioblastoma multiforme: A meta-analysis of individual patient data and a systematic review.
Seizure
PUBLISHED: 05-19-2014
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Glioblastoma multiforme (GBM) is the most lethal type of primary brain tumor, and patients that undergo the maximum tumor resection that is safely possible and standard radiochemotherapy only achieve a median survival time of 14.6 months. Several clinical studies have reported that valproic acid could prolong survival of GBM patients. However, the results of these studies are inconsistent. We examined relevant studies and conducted a meta-analysis to assess the effects of VPA on survival times and recurrence.
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Effect of extruding full-fat soy flakes on trans fat content.
ScientificWorldJournal
PUBLISHED: 05-08-2014
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To evaluate the effects of extrusion process on the trans fatty acids (TFAs) formation in soybean crude oils, three different extrusion parameters, namely, extrusion temperature (80-160 °C), feed moisture (10-26%), and screw speed (100-500 rpm), were carried out. It was found that only five different types of TFAs were detected out using gas chromatography-mass spectrometry. Before the extrusion started, the initial amount of total TFAs was 3.04 g/100 g. However, after extruding under every level of any variable, the total amounts of TFAs were significantly higher than those in the control sample (P < 0.05). For example, taking the effect of extrusion temperature into account, we can find that the highest amount of total of trans fatty acid (TTFA) was 1.62 times the amount of that in the control sample, whereas the lowest amount of TTFA was 1.54 times the amount of that in the control sample. Importantly, it was observed that the amounts of every type of trans fatty acid were not continuously increasing with the increase of the level of any extrusion variable. This phenomenon demonstrated that the formation and diversification were intricate during extruding process and need to be further studied.
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Geniposide plays an anti-inflammatory role via regulating TLR4 and downstream signaling pathways in lipopolysaccharide-induced mastitis in mice.
Inflammation
PUBLISHED: 04-29-2014
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Geniposide is a medicine isolated from Gardenia jasminoides Ellis, which is a traditional Chinese herb that is widely used in Asia for the treatment of inflammation, brain diseases, and hepatic disorders. Mastitis is a highly prevalent and important infectious disease. In this study, we used a lipopolysaccharide (LPS)-induced mouse mastitis model and LPS-stimulated primary mouse mammary epithelial cells (mMECs) to explore the anti-inflammatory effect and the mechanism of action of geniposide. Using intraductal injection of LPS as a mouse model of mastitis, we found that geniposide significantly reduced the infiltration of inflammatory cells and downregulated the production of tumor necrosis factor-? (TNF-?), interleukin-1? (IL-1?), and interleukin-6 (IL-6). To further investigate the anti-inflammatory mechanism, we used LPS-stimulated mMECs as an in vitro mastitis model. The results of enzyme-linked immunosorbent assay (ELISA) and quantitative real-time polymerase chain reaction (qRT-PCR) showed that geniposide inhibited the expression of TNF-?, IL-1?, and IL-6 in a dose-dependent manner. Western blot analysis demonstrated that geniposide could suppress the phosphorylation of inhibitory kappa B (I?B?), nuclear factor-?B (NF-?B), p38, extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK). Geniposide also inhibited the expression of toll-like receptor 4 (TLR4) in the LPS-stimulated mMECs. In conclusion, geniposide exerted its anti-inflammatory effect by regulating TLR4 expression, which affected the downstream NF-?B and mitogen-activated protein kinase (MAPK) signaling pathways. Thus, geniposide may be a potential drug for mastitis therapy.
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Occurrence of Sudan I in Paprika Fruits Caused by Agricultural Environmental Contamination.
J. Agric. Food Chem.
PUBLISHED: 04-29-2014
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Current research has demonstrated the presence of sub parts per billion levels of Sudan dye in paprika fruits during the vegetation process, which is difficult to understand on the basis of the conventional concept of cross-contamination or malicious addition. Detailed surveys on Sudan dyes I-IV in paprika fruits, soils, and agronomic materials used from seven fields of Xinjiang (China) were conducted to investigate the natural contamination. Results revealed that Sudan dyes II-IV were never detected and that Sudan I existed in almost all samples except for the mulching film and irrigation water. The higher total amount of Sudan I in soils, pesticides, and fertilizers compared to coated seeds indicated the combination of Sudan I-contaminated soils and application of Sudan I-containing agronomic materials constitutes a major source of 0.18-2.52 ?g/kg levels of Sudan I in fruits during the growth period. The study offers a more reasonable explanation for the previously observed Sudan I in paprika fruits.
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P450 enzyme-inducing and non-enzyme-inducing antiepileptic drugs for seizure prophylaxis after glioma resection surgery: a meta-analysis.
Seizure
PUBLISHED: 04-28-2014
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The prognoses of seizure treatment with P450 enzyme-inducing and non-enzyme-inducing antiepileptic drugs after glioma resection surgery were investigated across several clinical studies. However, the results of these studies are inconsistent. We examined the relevant studies and conducted a meta-analysis of these two types of anti-epileptic drugs.
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Cyanidin-3-O-?-glucoside inhibits lipopolysaccharide-induced inflammatory response in mouse mastitis model.
J. Lipid Res.
PUBLISHED: 04-21-2014
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Cyanidin-3-O-?-glucoside (C3G) (CAS number 7084-24-4), a typical anthocyanin pigment that exists in the human diet, has been reported to have anti-inflammatory properties. However, the effect of C3G on lipopolysaccharide (LPS)-induced mastitis and the molecular mechanisms have not been investigated. In this study, we detected the protective effects of C3G on a LPS-induced mouse mastitis model and investigated the molecular mechanisms in LPS-stimulated mouse mammary epithelial cells (MMECs). Our results showed that C3G could attenuate mammary histopathologic changes and myeloperoxidase activity, and inhibit TNF-?, interleukin (IL)-1?, and IL-6 production caused by LPS. Meanwhile, C3G dose-dependently inhibited TNF-? and IL-6 in LPS-stimulated MMECs. C3G suppressed LPS-induced nuclear factor-?B (NF-?B) and interferon regulatory factor 3 (IRF3) activation. Furthermore, C3G disrupted the formation of lipid rafts by depleting cholesterol. Moreover, C3G activated liver X receptor (LXR)-ABCG1-dependent cholesterol efflux. Knockdown of LXR? abrogated the anti-inflammatory effects of C3G. In conclusion, C3G has a protective effect on LPS-induced mastitis. The promising anti-inflammatory mechanisms of C3G are associated with upregulation of the LXR?-ABCG1 pathway which result in disrupting lipid rafts by depleting cholesterol, thereby suppressing toll-like receptor 4-mediated NF-?B and IRF3 signaling pathways induced by LPS.
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Green algae (Chlorella pyrenoidosa) adsorbs Bacillus thurigiensis (Bt) toxin, Cry1Ca insecticidal protein, without an effect on growth.
Ecotoxicol. Environ. Saf.
PUBLISHED: 04-11-2014
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The effect of purified Cry1Ca insecticidal protein on the growth of Chlorella pyrenoidosa was studied in a three-generation toxicity test. The C. pyrenoidosa medium with a density of 5.4 × 10(5) cells/mL was subcultured for three generations with added Cry1Ca at 0, 10, 100, and 1000 µg/L, and cell numbers were determined daily. To explore the distribution of Cry1Ca in C. pyrenoidosa and the culture medium, Cry1Ca was added at 1000 µg/L to algae with a high density of 4.8 × 10(6) cells/mL, and Cry1Ca content was determined daily in C. pyrenoidosa and the culture medium by enzyme-linked immunosorbent assays. Our results showed that the growth curves of C. pyrenoidosa exposed to 10, 100, and 1000 µg/L of Cry1Ca almost overlapped with that of the blank control, and there were no statistically significant differences among the four treatments from day 0 to day 7, regardless of generation. Moreover, the Cry1Ca content in the culture medium and in C. pyrenoidosa sharply decreased under exposure of 1000 µg/L Cry1Ca with high initial C. pyrenoidosa cell density. The above results demonstrate that Cry1Ca in water can be rapidly adsorbed and degraded by C. pyrenoidosa, but it has no suppressive or stimulative effect on algae growth.
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Acellular blood vessels combined human hair follicle mesenchymal stem cells for engineering of functional arterial grafts.
Ann Biomed Eng
PUBLISHED: 03-30-2014
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Tissue-engineered vessels offer options for autologous vascular grafts in cardiovascular repair and regeneration. The experiments aimed to construct functional arterial grafts by combining human hair follicle mesenchymal stem cells (HF-MSCs) with acellular umbilical arteries. We isolated mesenchymal stem cells from human hair follicles. Under appropriate culture conditions, these cells displayed CD44, CD90 and CD105, and exhibited the potential for differentiation to adipocytes, osteoblasts and chondrocytes. Very promisingly, HF-MSCs expressed the vascular smooth muscle specific markers in the presence of transforming growth factor-?. We created acellular arterial scaffolds by digesting human umbilical arteries with trypsin and sodium dodecyl sulfate. These acellular arterial scaffolds retained major components of the extracellular matrix. The mechanical properties of these acellular arterial scaffolds were very similar to those of native blood vessels. We then seeded HF-MSCs into acellular arterial scaffolds and found that they still expressed vascular smooth muscle specific markers. The arterial grafts derived from HF-MSCs demonstrated vasoreactivity in response to humoral constrictors. We constructed arterial grafts that are very close to native blood vessels in their structures and physiological functions. These properties suggest that these arterial grafts could be used as small diameter arterial grafts for cardiovascular repair and regeneration.
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Niacin attenuates the production of pro-inflammatory cytokines in LPS-induced mouse alveolar macrophages by HCA2 dependent mechanisms.
Int. Immunopharmacol.
PUBLISHED: 03-23-2014
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Niacin has been reported to have potent anti-inflammatory effects in LPS-induced acute lung injury. However, the molecular mechanism of niacin has not been fully understood. The aim of the present study was to investigate the effects of niacin on the production of pro-inflammatory cytokines TNF-?, IL-6 and IL-1? in LPS-induced mouse alveolar macrophages and explore its underlying mechanism. Mouse alveolar macrophages were incubated in the presence or absence of various concentrations of niacin (1, 10, 100?mol/l) 1h before LPS (1?g/ml) challenge. The results showed that niacin reduced the levels of TNF-?, IL-6 and IL-1? in LPS-challenged alveolar macrophages. Furthermore, NF-?B activation was inhibited by niacin through blocking the phosphorylation of NF-?B p65 and I?B?. In addition, silencing HCA2 abrogated the effect of niacin on the production of pro-inflammatory cytokines. These findings suggested that niacin attenuated the LPS-induced pro-inflammatory cytokines possibly mediated by HCA2 in LPS-challenged alveolar macrophages.
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Glycyrrhizin inhibits the inflammatory response in mouse mammary epithelial cells and a mouse mastitis model.
FEBS J.
PUBLISHED: 03-22-2014
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Glycyrrhizin, a triterpene glycoside isolated from licorice root, is known to have anti-inflammatory activities. However, the effect of glycyrrhizin on mastitis has not been reported. The purpose of this study was to investigate the anti-inflammatory effect and mechanism of action of glycyrrhizin on lipopolysaccharide (LPS)-induced mastitis in mouse. An LPS-induced mouse mastitis model was used to confirm the anti-inflammatory activity of glycyrrhizin in vivo. Primary mouse mammary epithelial cells were used to investigate the molecular mechanism and targets of glycyrrhizin. In vivo, glycyrrhizin significantly attenuated the mammary gland histopathological changes, myeloperoxidase activity and infiltration of neutrophilic granulocytes and downregulated the expression of tumor necrosis factor-?, interleukin (IL)-1? and IL-6 caused by LPS. In vitro, glycyrrhizin dose-dependently inhibited the LPS-induced expression of tumor necrosis factor-?, IL-6, and RANTES. Western blot analysis showed that glycyrrhizin suppressed LPS-induced nuclear factor-?B and interferon regulatory factor 3 activation. However, glycyrrhizin did not inhibit nuclear factor-?B and interferon regulatory factor 3 activation induced by MyD88-dependent (MyD88, IKK?) or TRIF-dependent (TRIF, TBK1) downstream signaling components. Moreover, glycyrrhizin did not act though affecting the function of CD14 or expression of Toll-like receptor 4. Finally, we showed that glycyrrhizin decreased the levels of cholesterol of lipid rafts and inhibited the translocation of Toll-like receptor 4 to lipid rafts. Moreover, glycyrrhizin activated ATP-binding cassette transporter A1, which could induce cholesterol efflux from lipid rafts. In conclusion, we find that the anti-inflammatory effects of glycyrrhizin may be attributable to its ability to activate ATP-binding cassette transporter A1. Glycyrrhizin might be a useful therapeutic reagent for the treatment of mastitis and other inflammatory diseases.
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Schisantherin A protects lipopolysaccharide-induced acute respiratory distress syndrome in mice through inhibiting NF-?B and MAPKs signaling pathways.
Int. Immunopharmacol.
PUBLISHED: 03-06-2014
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Acute respiratory distress syndrome (ARDS) is characterized by polymorphonuclear neutrophils (PMNs) adhesion, activation, sequestration and inflammatory damage to alveolar-capillary membrane. Schisantherin A, a dibenzocyclooctadiene lignan isolated from the fruit of Schisandra sphenanthera, has been reported to have anti-inflammatory properties. In the present study, we aimed to investigate the protective effects of schisantherin A on LPS-induced mouse ARDS. The pulmonary injury severity was evaluated 7 h after LPS administration and the protective effects of schisantherin A on LPS-induced mouse ARDS were assayed by enzyme-linked immunosorbent assay and Western blot. The results revealed that the wet/dry weight ratio, myeloperoxidase activity, and the number of total cells, neutrophils and macrophages in the bronchoalveolar lavage fluid (BALF) were significantly reduced by schisantherin A in a dose-dependent manner. Meanwhile, pretreatment with schisantherin A markedly ameliorated LPS-induced histopathologic changes and decreased the levels of tumor necrosis factor-? (TNF-?), interleukin-6 (IL-6) and interleukin-1? (IL-1?) in the BALF. In addition, the phosphorylation of nuclear transcription factor-kappaB (NF-?B) p65, inhibitory kappa B alpha (I?B-?), c-jun NH2-terminal kinase (JNK), extracellular signal-regulated kinase (ERK) and p38 induced by LPS were suppressed by schisantherin A. These findings indicated that schisantherin A exerted potent anti-inflammatory properties in LPS-induced mouse ARDS, possibly through blocking the activation of NF-KB and mitogen activated protein kinases (MAPKs) signaling pathways. Therefore, schisantherin A may be a potential agent for the prophylaxis of ARDS.
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Cyanidin-3-O-?-glucoside ameliorates lipopolysaccharide-induced acute lung injury by reducing TLR4 recruitment into lipid rafts.
Biochem. Pharmacol.
PUBLISHED: 03-06-2014
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Cyanidin-3-O-?-glucoside (C3G), a typical anthocyanin pigment that exists in the human diet, has been reported to have anti-inflammatory properties. The aim of this study was to detect the effect of C3G on LPS-induced acute lung injury and to investigate the molecular mechanisms. Acute lung injury was induced by intratracheal administration of LPS in mice. Alveolar macrophages from mice were stimulated with LPS and were treated with C3G. Our results showed that C3G attenuated lung histopathologic changes, myeloperoxidase (MPO) activity, TNF-?, IL-1? and IL-6 production in LPS-induced acute lung injury model. In vitro, C3G dose-dependently inhibited TNF-?, IL-1?, IL-6, IL-10 and IFN-? production, as well as NF-?B and IRF3 activation in LPS-stimulated alveolar macrophages. Furthermore, C3G disrupted the formation of lipid rafts by depleting cholesterol and inhibited TLR4 translocation into lipid rafts. Moreover, C3G activated LXR?-ABCG1-dependent cholesterol efflux. Knockout of LXR? abrogated the anti-inflammatory effects of C3G. In conclusion, C3G has a protective effect on LPS-induced acute lung injury. The promising anti-inflammatory mechanisms of C3G is associated with up-regulation of the LXR?-ABCG1 pathway which result in disrupting lipid rafts by depleting cholesterol and reducing translocation of TLR4 to lipid rafts, thereby suppressing TLR4 mediated inflammatory response.
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Thymol attenuates allergic airway inflammation in ovalbumin (OVA)-induced mouse asthma.
Fitoterapia
PUBLISHED: 03-01-2014
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Thymol, a naturally occurring monocyclic phenolic compound derived from Thymus vulgaris (Lamiaceae), has been reported to exhibit anti-inflammatory property in vivo and vitro. However, the mechanism of thymol is not clear. The aim of the present study was to investigate the effects of thymol on allergic inflammation in OVA-induced mice asthma and explore its mechanism. The model of mouse asthma was established by the induction of OVA. Thymol was orally administered at a dose of 4, 8, and 16 mg/kg body weight 1h before OVA challenge. At 24h after the last challenge, mice were sacrificed, and the data were collected by various experimental methods. The results revealed that pretreatment with thymol reduced the level of OVA-specific IgE, inhibited recruitment of inflammatory cells into airway, and decreased the levels of IL-4, IL-5, and IL-13 in BALF. Moreover, the pathologic changes of lung tissues were obviously ameliorated and goblet cell hyperplasia was effectively inhibited by the pretreatment of thymol. In addition, thymol reduced the development of airway hyperresponsiveness and blocked the activation of NF-?B pathway. All data suggested that thymol ameliorated airway inflammation in OVA-induced mouse asthma, possibly through inhibiting NF-?B activation. These findings indicated that thymol may be used as an alternative agent for treating allergic asthma.
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Nitrogen and phosphorus dual-doped hierarchical porous carbon foams as efficient metal-free electrocatalysts for oxygen reduction reactions.
Chemistry
PUBLISHED: 02-12-2014
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Despite tremendous progress in developing doped carbocatalysts for the oxygen reduction reaction (ORR), the ORR activity of current metal-free carbocatalysts is still inferior to that of conventional Pt/C catalysts, especially in acidic media and neutral solution. Moreover, it also remains a challenge to develop an effective and scalable method for the synthesis of metal-free carbocatalysts. Herein, we have developed nitrogen and phosphorus dual-doped hierarchical porous carbon foams (HP-NPCs) as efficient metal-free electrocatalysts for ORR. The HP-NPCs were prepared for the first time by copyrolyzing nitrogen- and phosphorus-containing precursors and poly(vinyl alcohol)/polystyrene (PVA/PS) hydrogel composites as in situ templates. Remarkably, the resulting HP-NPCs possess controllable nitrogen and phosphorus content, high surface area, and a hierarchical interconnected macro-/mesoporous structure. In studying the effects of the HP-NPCs on the ORR, we found that the as-prepared HP-NPC materials exhibited not only excellent catalytic activity for ORR in basic, neutral, and acidic media, but also much better tolerance for methanol oxidation and much higher stability than the commercial, state-of-the-art Pt/C catalysts. Because of all these outstanding features, it is expected that the HP-NPC material will be a very suitable catalyst for next-generation fuel cells and lithium-air batteries. In addition, the novel synthetic method described here might be extended to the preparation of many other kinds of hierarchical porous carbon materials or porous carbon that contains metal oxide for wide applications including energy storage, catalysis, and electrocatalysis.
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rs744166 polymorphism of the STAT3 gene is associated with risk of gastric cancer in a Chinese population.
Biomed Res Int
PUBLISHED: 02-11-2014
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The aim of this study was to explore the association between polymorphisms in signal transducer and activator of transcription protein 3 (STAT3) and the risk of gastric cancer. In the present study, a case-control study was conducted in which rs2293152 and rs744166 polymorphisms in STAT3 were analyzed in 209 Chinese patients with gastric cancer and 294 cancer-free controls. The genotypes were determined by polymerase chain reaction restriction fragment length polymorphism method. For the rs744166 polymorphism, the TC genotype (adjusted OR = 0.60, 95% CI = 0.39-0.92, and P = 0.020) and CC genotype (adjusted OR = 0.41, 95% CI = 0.21-0.80, and P = 0.009) were associated with a decreased risk of gastric cancer compared to the TT genotype. However, rs2293152 did not show any difference in gastric cancer risk between patients and controls in the CG/CC genotype compared to the GG genotype. Besides, the SNP effects were additive to the effects of environmental factors without any interaction between them in the susceptibility to gastric cancer. Collectively, rs744166 polymorphism might be significantly associated with a decreased risk of gastric cancer in a Chinese population. Additionally, polymorphisms in STAT3, along with environmental factors, might be associated with the development of gastric cancer.
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Development of a reverse transcription loop-mediated isothermal amplification method for the rapid detection of subtype H7N9 avian influenza virus.
Biomed Res Int
PUBLISHED: 02-06-2014
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A novel influenza A (H7N9) virus has emerged in China. To rapidly detect this virus from clinical samples, we developed a reverse transcription loop-mediated isothermal amplification (RT-LAMP) method for the detection of the H7N9 virus. The minimum detection limit of the RT-LAMP assay was 0.01 PFU H7N9 virus, making this method 100-fold more sensitive to the detection of the H7N9 virus than conventional RT-PCR. The H7N9 virus RT-LAMP assays can efficiently detect different sources of H7N9 influenza virus RNA (from chickens, pigeons, the environment, and humans). No cross-reactive amplification with the RNA of other subtype influenza viruses or of other avian respiratory viruses was observed. The assays can effectively detect H7N9 influenza virus RNA in drinking water, soil, cloacal swab, and tracheal swab samples that were collected from live poultry markets, as well as human H7N9 virus, in less than 30 min. These results suggest that the H7N9 virus RT-LAMP assays were efficient, practical, and rapid diagnostic methods for the epidemiological surveillance and diagnosis of influenza A (H7N9) virus from different resource samples.
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Effects of niacin on Staphylococcus aureus internalization into bovine mammary epithelial cells by modulating NF-?B activation.
Microb. Pathog.
PUBLISHED: 02-05-2014
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Niacin is a precursor of coenzymes NAD and NADP and plays a critical role in electron transfer during the metabolic process. In addition to its nutrimental function, niacin has long been used for the treatment of lipid disorders and cardiovascular disease. However, the effect of niacin on Staphylococcus aureus (S. aureus) internalization into bovine mammary epithelial cells (bMEC) remains unclear. Here we sought to examine the effect of niacin on S. aureus internalization into bovine mammary epithelial cells (bMEC) and to investigate the potential mechanism. In this study, the growth of S. aureus supplemented with niacin (0.5-2 mM) was monitored turbidimetrically at 600 nm for 24 h and cell viability was measured by MTT assay. Gentamicin protection assay was carried out to determine the effect of niacin on S. aureus internalization into bMEC. To determine the potential mechanism, tracheal antimicrobial peptide (TAP) and ?-defensin (BNBD5) expressions were detected by quantitative real-time polymerase chain reaction (qRT-PCR). The activation of nuclear factor-kappa B (NF-?B) was determined by Western blotting. The results showed that niacin (0.5-2 mM) did not affect S. aureus growth and bMEC viability, whereas it inhibits S. aureus internalization ranging from 13% to 42% and down-regulated the mRNA expression of TAP and BNBD5 compared to the control group. No exactly relationship was discovered between S. aureus internalization into bMEC and antimicrobial peptide expression, while niacin inhibited S. aureus-induced NF-?B activation in a dose manner. These dates suggest that inhibiting NF-?B activation may be the potential mechanism of niacin on modulating S. aureus internalization into bMEC.
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Serum Helicobacter pylori NapA antibody as a potential biomarker for gastric cancer.
Sci Rep
PUBLISHED: 02-04-2014
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Helicobacter pylori (H. pylori) infection is strongly associated with gastric cancer. However, only a minority of infected individuals ever develop gastric cancer. This risk stratification may be in part due to differences among strains. The relationship between neutrophil-activating protein (NapA) and gastric cancer is unclear. The purpose of this study is to evaluate the significance of NapA as a biomarker in gastric cancer. We used enzyme linked immunosorbent assay (ELISA) to determine the status of H. pylori infection. Indirect ELISA method was used for detection of NapA antibody titer in the serum of H. pylori infected individuals. Unconditional logistic regressions were adopted to analyze the variables and determine the association of NapA and gastric cancer. The results of study indicated serum H. pylori NapA antibody level were associated with a reduced risk for development of gastric cancer. It may be used in conjugation with other indicators for gastric cancer detection.
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Expression of Cry1Ab protein in a marker-free transgenic Bt rice line and its efficacy in controlling a target pest, Chilo suppressalis (Lepidoptera: Crambidae).
Environ. Entomol.
PUBLISHED: 02-03-2014
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A marker-free Bt transgenic rice line, mfb-MH86, was recently developed in China, which contains a cry1Ab gene driven by a ubiquitin promoter. This Bt gene confers resistance to a range of lepidopteran species, including the striped stem borer, Chilo suppressalis (Walker). The expression of Cry1Ab protein in mfb-MH86 leaves, stems and leaf sheaths (hereinafter referred to as stems), and roots was evaluated throughout the rice-growing season using an enzyme-linked immunosorbent assay. In addition, mfb-MH86 resistance to C. suppressalis, a major pest of rice, was evaluated in a laboratory bioassay with field-collected rice stems. Cry1Ab protein levels of mfb-MH86 were highest in leaves (9.71-34.09 ?g/g dry weight [DW]), intermediate in stems (7.66-18.51 ?g/g DW), and lowest in roots (1.95-13.40 ?g/g DW). In all tissues, Cry1Ab levels in mfb-MH86 were higher in seedling and tillering stages than in subsequent growth stages. In the laboratory bioassay, mortality of C. suppressalis after 6 d of feeding on mfb-MH86 stems was 100% throughout the rice-growing season; mortality of C. suppressalis when feeding on stems of the nontransformed isoline, MH86, ranged from 15.0 to 38.3%. The results indicate that Cry1Ab protein levels in mfb-MH86 stems are sufficient to protect plants against C. suppressalis throughout the rice-growing season. Although our results are promising, further comprehensive evaluations of mfb-MH86, including field surveys, will be needed before commercial use.
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Reconstructing full-length ureteral defects using a spiral bladder muscle flap with vascular pedicles.
Urology
PUBLISHED: 01-27-2014
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This study investigates the efficacy of ureteral reconstruction using a spiral bladder muscle flap with vascular pedicles (ie, the superior vesical arteries) to repair full-length ureteral defects and explores a surgical approach for repairing long ureteral defects (>20 cm) using a bladder muscle flap.
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Thymol inhibits Staphylococcus aureus internalization into bovine mammary epithelial cells by inhibiting NF-?B activation.
Microb. Pathog.
PUBLISHED: 01-24-2014
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Bovine mastitis is one of the most costly and prevalent diseases in the dairy industry and is characterised by inflammatory and infectious processes. Staphylococcus aureus (S. aureus), a Gram-positive organism, is a frequent cause of subclinical, chronic mastitis. Thymol, a monocyclic monoterpene compound isolated from Thymus vulgaris, has been reported to have antibacterial properties. However, the effect of thymol on S. aureus internalization into bovine mammary epithelial cells (bMEC) has not been investigated. In this study, we evaluated the effect of thymol on S. aureus internalization into bMEC, the expression of tracheal antimicrobial peptide (TAP) and ?-defensin (BNBD5), and the inhibition of NF-?B activation in bMEC infected with S. aureus. Our results showed that thymol (16-64 ?g/ml) could reduce the internalization of S. aureus into bMEC and down-regulate the mRNA expression of TAP and BNBD5 in bMEC infected with S. aureus. In addition, thymol was found to inhibit S. aureus-induced nitric oxide (NO) production in bMEC and suppress S. aureus-induced NF-?B activation in a dose-dependent manner. In conclusion, these results indicated that thymol inhibits S. aureus internalization into bMEC by inhibiting NF-?B activation.
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Building nanocomposite magnets by coating a hard magnetic core with a soft magnetic shell.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 01-22-2014
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Controlling exchange coupling between hard magnetic and soft magnetic phases is the key to the fabrication of advanced magnets with tunable magnetism and high energy density. Using FePt as an example, control over the magnetism in exchange-coupled nanocomposites of hard magnetic face-centered tetragonal (fct) FePt and soft magnetic Co (or Ni, Fe2C) is shown. The dispersible hard magnetic fct-FePt nanoparticles are first prepared with their coercivity (Hc) reaching 33?kOe. Then core/shell fct-FePt/Co (or Ni, Fe2C) nanoparticles are synthesized by reductive thermal decomposition of the proper metal precursors in the presence of fct-FePt nanoparticles. These core/shell nanoparticles are strongly coupled by exchange interactions and their magnetic properties can be rationally tuned by the shell thickness of the soft phase. This work provides an ideal model system for the study of exchange coupling at the nanoscale, which will be essential for building superstrong magnets for various permanent magnet applications in the future.
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nBu4NI-catalyzed oxidative imidation of ketones with imides: synthesis of ?-amino ketones.
Chem. Commun. (Camb.)
PUBLISHED: 01-22-2014
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nBu4NI-Catalyzed oxidative imidation of ketones and imides for the synthesis of ?-amino ketones were realized for the first time. The methodology is characterized by its wide substrate scope even for acetone with readily available phthalimide, saccharin and succinimide, which opens a new pathway for direct imidation of ketones.
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Neoadjuvant intra-arterial chemotherapy followed by total laparoscopic radical trachelectomy in stage IB1 cervical cancer.
Fertil. Steril.
PUBLISHED: 01-16-2014
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To support the feasibility and safety of neoadjuvant intra-arterial chemotherapy followed by total laparoscopic radical trachelectomy in stage IB1 cervical cancer with tumor larger than 2 cm.
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Glycyrrhizin inhibits lipopolysaccharide-induced inflammatory response by reducing TLR4 recruitment into lipid rafts in RAW264.7 cells.
Biochim. Biophys. Acta
PUBLISHED: 01-14-2014
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The aim of this study was to investigate the effect of glycyrrhizin on LPS-induced endotoxemia in mice and clarify the possible mechanism.
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Bt rice producing Cry1C protein does not have direct detrimental effects on the green lacewing Chrysoperla sinica (Tjeder).
Environ. Toxicol. Chem.
PUBLISHED: 01-13-2014
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The effects of insect-resistant genetically engineered rice producing Cry1C protein derived from Bacillus thuringiensis (Bt) on Chrysoperla sinica (Tjeder) (Neuroptera: Chrysopidae) were assessed in laboratory bioassays. Survival and development of C. sinica larvae were not adversely affected when the larvae were fed a diet containing purified Cry1C protein at 200?µg/g fresh weight, representing a worst-case exposure scenario; in contrast, C. sinica larvae were adversely affected when the diet contained avidin or potassium arsenate. Life table parameters of C. sinica adults did not differ when the adults were fed with Bt or non-Bt rice pollen together with a 2-M sucrose solution. Life table parameters of C. sinica adults also did not differ when the adults were fed an artificial diet with or without purified Cry1C protein at a nominal concentration that was approximately 20 times higher than that in rice pollen; in contrast, C. sinica adults were adversely affected when the diet contained potassium arsenate. In all bioassays with lacewings, the bioactivity and stability of the Cry1C protein in the diet and Cry1C protein uptake by the lacewings were confirmed by enzyme-linked immunosorbent assay (ELISA) and by bioassays with a Cry1C-sensitive lepidopteran. These results demonstrate that neither larvae nor adults of C. sinica are sensitive to Cry1C protein at concentrations higher than those encountered in the field, demonstrating that the growing of Bt rice producing Cry1C protein is unlikely to pose a risk to C. sinica.
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Protective effect of taraxasterol on acute lung injury induced by lipopolysaccharide in mice.
Int. Immunopharmacol.
PUBLISHED: 01-11-2014
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Taraxasterol, a pentacyclic-triterpene isolated from Taraxacum officinale, has been reported to have potent anti-inflammatory properties. However, the effect of taraxasterol on lipopolysaccharide (LPS)-induced mice acute lung injury has not been investigated. The aims of this study were to investigate whether taraxasterol could ameliorate the inflammation response in LPS-induced acute lung injury and to clarify the possible mechanism. Male BALB/c mice were pretreated with taraxasterol 1h before intranasal instillation of LPS. 7h after LPS administration, the myeloperoxidase (MPO) in lung tissues, lung wet/dry ratio and inflammatory cells in the bronchoalveolar lavage fluid (BALF) were detected. The levels of tumor necrosis factor-? (TNF-?), interleukin-6 (IL-6), interleukin-1? (IL-1?) in the BALF were measured by ELISA. The extent of phosphorylation of I?B-?, p65 NF-?B, p46-p54 JNK, p42-p44 ERK, and p38 were determined by western blotting. The results showed that taraxasterol attenuated the infiltration of inflammatory cells, the activity of myeloperoxidase (MPO), lung wet/dry ratio, and the expression of tumor necrosis factor-? (TNF-?), interleukin-6 (IL-6) and interleukin-1? (IL-1?) in a dose-dependent manner. Additionally, western blotting results showed that taraxasterol inhibited the phosphorylation of I?B-?, p65 NF-?B, p46-p54 JNK, p42-p44 ERK, and p38 caused by LPS. Our data suggest that anti-inflammatory effects of taraxasterol against the LPS-induced ALI may be due to its ability of inhibition of the NF-?B and MAPK signaling pathways.
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Effect of straw leachates from Cry1Ca-expressing transgenic rice on the growth of Chlorella pyrenoidosa.
Environ. Toxicol. Chem.
PUBLISHED: 01-07-2014
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Because of the prevalence of algae in rice paddy fields, they will be exposed to Bacillus thurigiensis (Bt) proteins released from Bt protein-expressing genetically engineered rice. To assess the effects of leachates extracted from Cry1Ca-expressing transgenic rice (T1C-19) straw on the microalga Chlorella pyrenoidosa, the authors added purified Cry1Ca (10?µg/L, 100?µg/L, and 1000?µg/L) and 5 concentrations of diluted extracts (5%, 10%, 20%, 40%, and 80%) from T1C-19 and the nontransformed control strain Minghui 63 (MH63) to the medium of C. pyrenoidosa. The authors found that the growth curves of C. pyrenoidosa treated with purified Cry1Ca overlapped with the medium control; that the order of C. pyrenoidosa growth rates for the T1C-19 leachate concentrations was 5%?>?10%?>?20%?>?control?>?40%?>?80%, and for the MH63 concentrations the order was 5%?>?10%?>?control?>?20%?>?40%?>?80%, but there were no statistical differences between the 20% T1C-19 or 20% MH63 leachate treatment and the medium control on day 8; and that after 7 d of culture, Cry1Ca could be detected in C. pyrenoidosa treated with different concentrations of T1C-19 leachate. The results demonstrated that Cry1Ca protein released from T1C-19 rice can be absorbed into C. pyrenoidosa but that purified Cry1Ca and leachates from T1C-19 rice have no obvious adverse effects on the growth of C. pyrenoidosa.
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Curcumin attenuates inflammatory responses by suppressing TLR4-mediated NF-?B signaling pathway in lipopolysaccharide-induced mastitis in mice.
Int. Immunopharmacol.
PUBLISHED: 01-04-2014
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Curcumin, the main constituent of the spice turmeric, has been reported to have potent anti-inflammatory properties. However, the effect of curcumin on lipopolysaccharide (LPS)-induced mice mastitis has not been investigated. The aim of this study was to investigate whether curcumin could ameliorate the inflammation response in LPS-induced mice mastitis and to clarify the possible mechanism. The mouse model of mastitis was induced by injection of LPS through the duct of the mammary gland. Curcumin was applied 1h before and 12h after LPS treatment. The results showed that curcumin attenuated the infiltration of inflammatory cells, the activity of myeloperoxidase (MPO), and the expression of tumor necrosis factor-? (TNF-?), interleukin-6 (IL-6) and interleukin-1? (IL-1?) in a dose-dependent manner. Additionally, Western blotting results showed that curcumin inhibited the phosphorylation of I?B-? and NF-?B p65 and the expression of TLR4. These results indicated that curcumin has protective effect on mice mastitis and the anti-inflammatory mechanism of curcumin on LPS-induced mastitis in mice may be due to its ability to inhibit TLR4-mediated NF-?B signaling pathways. Curcumin may be a potential therapeutic agent against mastitis.
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Biosafety management and commercial use of genetically modified crops in China.
Plant Cell Rep.
PUBLISHED: 01-03-2014
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As a developing country with relatively limited arable land, China is making great efforts for development and use of genetically modified (GM) crops to boost agricultural productivity. Many GM crop varieties have been developed in China in recent years; in particular, China is playing a leading role in development of insect-resistant GM rice lines. To ensure the safe use of GM crops, biosafety risk assessments are required as an important part of the regulatory oversight of such products. With over 20 years of nationwide promotion of agricultural biotechnology, a relatively well-developed regulatory system for risk assessment and management of GM plants has been developed that establishes a firm basis for safe use of GM crops. So far, a total of seven GM crops involving ten events have been approved for commercial planting, and 5 GM crops with a total of 37 events have been approved for import as processing material in China. However, currently only insect-resistant Bt cotton and disease-resistant papaya have been commercially planted on a large scale. The planting of Bt cotton and disease-resistant papaya have provided efficient protection against cotton bollworms and Papaya ringspot virus (PRSV), respectively. As a consequence, chemical application to these crops has been significantly reduced, enhancing farm income while reducing human and non-target organism exposure to toxic chemicals. This article provides useful information for the colleagues, in particular for them whose mother tongue is not Chinese, to clearly understand the biosafety regulation and commercial use of genetically modified crops in China.
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Chlorogenic acid attenuates lipopolysaccharide-induced mice mastitis by suppressing TLR4-mediated NF-?B signaling pathway.
Eur. J. Pharmacol.
PUBLISHED: 01-02-2014
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Chlorogenic acid (CGA), one of the most abundant polyphenols in the diet, has been reported to have potent anti-inflammatory properties. However, the effect of CGA on lipopolysaccharide (LPS)-induced mice mastitis has not been investigated. The purpose of the present study was to elucidate whether CGA could ameliorate the inflammation response in LPS-induced mice mastitis and to clarify the possible mechanism. The mouse model of mastitis was induced by injection of LPS through the duct of mammary gland. CGA was administered intraperitoneally with the dose of 12.5, 25, and 50mg/kg respectively 1h before and 12h after induction of LPS. In this study, the effect of CGA on LPS-induced mice mastitis was assessed through histopathological examination, ELISA assay, and western blot analysis. The results showed that CGA significantly reduced TNF-?, IL-1?, and IL-6 production compared with LPS group. Besides, western blot analysis showed that CGA could inhibit the expression of TLR4 and the phosphorylation of NF-?B and I?B induced by LPS. These results suggested that anti-inflammatory effects of CGA against LPS-induced mastitis may be due to its ability to inhibit TLR4-mediated NF-?B signaling pathway. Therefore, CGA may be a potent therapeutic reagent for the prevention of the immunopathology encountered during Escherichia coli elicited mastitis.
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Consumption of Bt rice pollen containing Cry1C or Cry2A protein poses a low to negligible risk to the silkworm Bombyx mori (Lepidoptera: Bombyxidae).
PLoS ONE
PUBLISHED: 01-01-2014
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By consuming mulberry leaves covered with pollen from nearby genetically engineered, insect-resistant rice lines producing Cry proteins derived from Bacillus thuringiensis (Bt), larvae of the domestic silkworm, Bombyx mori (Linnaeus) (Lepidoptera: Bombyxidae), could be exposed to insecticidal proteins. Laboratory experiments were conducted to assess the potential effects of Cry1C- or Cry2A-producing transgenic rice (T1C-19, T2A-1) pollen on B. mori fitness. In a short-term assay, B. mori larvae were fed mulberry leaves covered with different densities of pollen from Bt rice lines or their corresponding near isoline (control) for the first 3 d and then were fed mulberry leaves without pollen. No effect was detected on any life table parameter, even at 1800 pollen grains/cm(2) leaf, which is much higher than the mean natural density of rice pollen on leaves of mulberry trees near paddy fields. In a long-term assay, the larvae were fed Bt and control pollen in the same way but for their entire larval stage (approximately 27 d). Bt pollen densities ? 150 grains/cm(2) leaf reduced 14-d larval weight, increased larval development time, and reduced adult eclosion rate. ELISA analyses showed that 72.6% of the Cry protein was still detected in the pollen grains excreted with the feces. The low exposure of silkworm larvae to Cry proteins when feeding Bt rice pollen may be the explanation for the relatively low toxicity detected in the current study. Although the results demonstrate that B. mori larvae are sensitive to Cry1C and Cry2A proteins, the exposure levels that harmed the larvae in the current study are far greater than natural exposure levels. We therefore conclude that consumption of Bt rice pollen will pose a low to negligible risk to B. mori.
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A role of Rab29 in the integrity of the trans-Golgi network and retrograde trafficking of mannose-6-phosphate receptor.
PLoS ONE
PUBLISHED: 01-01-2014
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Rab29 (also referred as Rab7L1) is a novel Rab protein, and is recently demonstrated to regulate phagocytosis and traffic from the Golgi to the lysosome. However, its roles in membrane trafficking have not been investigated extensively. Our results in this study revealed that Rab29 is associated with the trans-Golgi network (TGN), and is essential for maintaining the integrity of the TGN, because inhibition of the activity of Rab29 or depletion of Rab29 resulted in fragmentation of the TGN marked by TGN46. Expression of the dominant negative form Rab29T21N or shRNA-Rab29 also altered the distribution of mannose-6-phosphate receptor (M6PR), and interrupted the retrograde trafficking of M6PR through monitoring the endocytosis of CD8-tagged calcium dependent M6PR (cdM6PR) or calcium independent M6PR (ciM6PR), but without significant effects on the anterograde trafficking of vesicular stomatitis virus G protein (VSV-G). Our results suggest that Rab29 is essential for the integrity of the TGN and participates in the retrograde trafficking of M6PRs.
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Rhinovirus-16 induced release of IP-10 and IL-8 is augmented by Th2 cytokines in a pediatric bronchial epithelial cell model.
PLoS ONE
PUBLISHED: 01-01-2014
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In response to viral infection, bronchial epithelial cells increase inflammatory cytokine release to activate the immune response and curtail viral replication. In atopic asthma, enhanced expression of Th2 cytokines is observed and we postulated that Th2 cytokines may augment the effects of rhinovirus-induced inflammation.
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Use of a pollen-based diet to expose the ladybird beetle Propylea japonica to insecticidal proteins.
PLoS ONE
PUBLISHED: 01-01-2014
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A rape seed pollen-based diet was developed and found to be suitable for use in a dietary exposure assay for Propylea japonica. Using the diet, we established and validated a dietary exposure assay by using the protease inhibitor E-64 as positive control. Dose-dependent responses were documented for all observed life-table parameters of P. japonica including survival, pupation and eclosion rates, development time and adult weight. Results suggested that the dietary assay can detect the effects of insecticidal compounds on the survival and development of P. japonica. Using the established dietary assay, we subsequently tested the toxicity of Cry1Ab, Cry1Ac and Cry1F proteins that are expressed by transgenic maize, cotton or rice plants to P. japonica larvae. The diet containing E-64 was included as a positive control. Survival and development of P. japonica larvae were not adversely affected when the diet contained purified Cry1Ab, Cry1Ac, or Cry1F at 500 µg/g diet representing a worst-case exposure scenario. In contrast, P. japonica larvae were adversely affected when the diet contained E-64. The bioactivity and stability of the Cry proteins in the diet and Cry protein uptake by the ladybird larvae were confirmed by bioassay with a Cry-sensitive insect species and by ELISA. The current study describes a suitable experimental system for assessing the potential effects of gut-active insecticidal compounds on ladybird beetle larvae. The experiments with the Cry proteins demonstrate that P. japonica larvae are not sensitive to Cry1Ab, Cry1Ac and Cry1F.
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Induced pluripotent stem cells from human hair follicle mesenchymal stem cells.
Stem Cell Rev
PUBLISHED: 12-16-2013
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Reprogramming of somatic cells into inducible pluripotent stem cells (iPSCs) provides an alternative to using embryonic stem cells (ESCs). Mesenchymal stem cells derived from human hair follicles (hHF-MSCs) are easily accessible, reproducible by direct plucking of human hairs. Whether these hHF-MSCs can be reprogrammed has not been previously reported. Here we report the generation of iPSCs from hHF-MSCs obtained by plucking several hairs. hHF-MSCs were isolated from hair follicle tissues and their mesenchymal nature confirmed by detecting cell surface antigens and multilineage differentiation potential towards adipocytes and osteoblasts. They were then reprogrammed into iPSCs by lentiviral transduction with Oct4, Sox2, c-Myc and Klf4. hHF-MSC-derived iPSCs appeared indistinguishable from human embryonic stem cells (hESCs) in colony morphology, expression of alkaline phosphotase, and expression of specific hESCs surface markers, SSEA-3, SSEA-4, Tra-1-60, Tra-1-81, Nanog, Oct4, E-Cadherin and endogenous pluripotent genes. When injected into immunocompromised mice, hHF-MSC-derived iPSCs formed teratomas containing representatives of all three germ layers. This is the first study to report reprogramming of hHF-MSCs into iPSCs.
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Investigation on the mechanism of water-assisted palladium-catalyzed benzylic C-H amination by N-fluorobenzenesulfonimide.
Org. Biomol. Chem.
PUBLISHED: 10-17-2013
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A combination of computational and experimental methods was carried out to elucidate the mechanism of palladium-catalyzed water-assisted benzylic C-H amination with N-fluorobenzenesulfonimide (NFSI), which involved the oxidative addition of Pd(II) to Pd(IV)-species as a rate-limiting step, followed by water-assisted concerted metalation-deprotonation (CMD) of the Pd(IV) complex and water-assisted reductive elimination (RE) processes, and then a nucleophilic addition process to generate the final product and complete the catalytic cycle. The stability of the Pd(IV) complex could be ascribed to the suitable ligands with strong ?-donors and resistance to decomposition, as well as being sufficiently bulky because the water-clusters assembled the ligands through hydrogen bonds to act as one multidentate ligand. Calculation results suggested that water also plays a crucial role as a proton transferring bridge in water-assisted CMD and RE processes. The corresponding experimental findings substantiate the expectation. Additionally, NFSI was found to act as both the oxidant and the nitrogen source to facilitate the reaction, while the steric effect of the bulky -N(SO2Ph)2 group contributed to circumventing the o-C-H amination. In this reaction, we investigated a novel spiro-cyclopalladation intermediate, formed by the reaction of the Pd(IV) centre with pristine-carbon instead of ortho-carbon, which might be valuable for our understanding and further development of transition metal catalyzed C-H functionalization.
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Polymorphisms of the TLR4 gene and risk of gastric cancer.
Gene
PUBLISHED: 10-14-2013
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Toll-like receptor 4 (TLR4) is an important lipo-polysaccharide (LPS) receptor in gastric epithelial cell signaling transduction and plays critical roles in the development and progression of gastric cancer (GC). We investigated the effects of TLR4 gene polymorphisms and gene-environmental interactions on the risk of GC in Northeastern China.
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Serum Antibody Against Helicobacter pylori FlaA and Risk of Gastric Cancer.
Helicobacter
PUBLISHED: 10-14-2013
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Helicobacter pylori (H. pylori) infection is a major risk factor for gastric cancer (GC); however, only a minority of infected individuals develops GC. We aim to assess the association between serostatus of antibody against H. pylori flagellin A (FlaA) and risk of GC and to evaluate the value of serum FlaA antibody as a novel screening biomarker for GC risk.
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Hydrophilic interaction ultra-performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry (HILIC-UPLC-TQ-MS/MS) in multiple-reaction monitoring (MRM) for the determination of nucleobases and nucleosides in ginkgo seeds.
Food Chem
PUBLISHED: 09-15-2013
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In this study, a rapid, simple and sensitive analytical method was developed for the quantitative determination of 20 nucleosides and nucleobases in functional foods at trace levels using hydrophilic interaction ultra-performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry (HILIC-UPLC-TQ-MS/MS) in multiple-reaction monitoring (MRM) mode. Under optimised chromatographic conditions, good separation of 20 target compounds was achieved using a Waters Acquity UPLC BEH Amide column and gradient elution in 11min. The limits of detection (LODs) and quantification (LOQs) were between 0.02-42.54ng/mL and 0.05-98.18ng/mL for the 20 analytes, respectively. This is the first report about simultaneous analysis of nucleosides and nucleobases in functional foods using this method, which afforded good linearity, precision, repeatability and accuracy. The method developed was successfully applied to quantify target compounds in batches of ginkgo seeds. The method potentially could be used to determine polar and trace-level nucleosides and nucleobases in ginkgo seeds.
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Bt rice expressing Cry2Aa does not cause direct detrimental effects on larvae of Chrysoperla sinica.
Ecotoxicology
PUBLISHED: 09-11-2013
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To assess the potential effects of Cry2Aa-expressing insect-resistant Bt rice on Chrysoperla sinica larvae, we conducted two tritrophic bioassays using a non-target (Laodelphax striatellus) and a target herbivore (Chilo suppressalis) as prey. None of the tested life-table parameters of C. sinica did differ when fed with L. striatellus nymphs reared on either Bt or control rice plants. Similarly, C. sinica larval survival and development were not affected when fed C. suppressalis larvae that were reared on Cry2Aa-contained artificial diet compared to those fed control diet. However, the 7-day larval weight was significantly decreased in the Bt treatment and none of the C. sinica larvae developed to the adult stage. To clarify whether the observed effects were due to the direct toxicity of Cry2Aa or prey-quality mediated, we conducted a dietary exposure assay in which the toxicity of Cry2Aa to C. sinica larvae was tested. Potassium arsenate (PA) was included as a positive control. None of the tested life-table parameters of C. sinica was adversely affected when fed Cry2Aa at 500 ?g/ml sucrose solution. In contrast, C. sinica larvae were adversely affected by feeding on sucrose solution containing PA. In the feeding assays, exposure of C. sinica larvae to Cry2Aa was confirmed by ELISA. Our results demonstrate that C. sinica larvae are not sensitive to Cry2Aa at concentrations exceeding the levels that the larvae may encounter in Bt rice fields. Consequently the detrimental effects observed in the tritrophic studies using Bt rice-fed C. suppressalis as prey can be attributed to the decreased prey quality due to the sensitivity of C. suppressalis larvae to Cry2Aa.
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Reductive amination of tertiary anilines and aldehydes.
Chem. Commun. (Camb.)
PUBLISHED: 08-22-2013
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An unprecedented oxidant-mediated reductive amination of tertiary anilines and aldehydes without external reducing agents was developed via the nucleophilic attack of the oxygen atom of the carbonyl group to in situ generated iminium ions, in which tertiary anilines were used as both nitrogen source and reducing agent for the first time.
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Staphylococcus aureus and Escherichia coli elicit different innate immune responses from bovine mammary epithelial cells.
Vet. Immunol. Immunopathol.
PUBLISHED: 08-07-2013
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Escherichia coli and Staphylococcus aureus are the most important pathogenic bacteria causing bovine clinical mastitis and subclinical mastitis, respectively. However, little is known about the molecular mechanisms underlying the different host response patterns caused by these bacteria. The aim of this study was to characterize the different innate immune responses of bovine mammary epithelium cells (MECs) to heat-inactivated E. coli and S. aureus. Gene expression of Toll-like receptor 2 (TLR2) and TLR4 was compared. The activation of nuclear factor kappa B (NF-?B) and the kinetics and levels of cytokine production were analyzed. The results show that the mRNA for TLR2 and TLR4 was up-regulated when the bovine MECs were stimulated with heat-inactivated E. coli, while only TLR2 mRNA was up-regulated when the bovine MECs were stimulated with heat-inactivated S. aureus. The expression of tumor necrosis factor-? (TNF-?), interleukin (IL)-1?, IL-6 and IL-8 increased more rapidly and higher when the bovine MECs were stimulated with heat-inactivated E. coli than when they were stimulated with heat-inactivated S. aureus. E. coli strongly activated NF-?B in the bovine MECs, while S. aureus failed to activate NF-?B. Heat-inactivated S. aureus could induce NF-?B activation when bovine MECs cultured in medium without fetal calf serum. These results were confirmed using TLR2- and TLR4/MD2-transfected HEK293 cells and suggested that differential TLR recognition and the lack of NF-?B activation account for the impaired immune response elicited by heat-inactivated S. aureus.
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OsAP65, a rice aspartic protease, is essential for male fertility and plays a role in pollen germination and pollen tube growth.
J. Exp. Bot.
PUBLISHED: 08-07-2013
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Aspartic proteases (APs) comprise a large proteolytic enzyme family widely distributed in animals, microbes, viruses, and plants. The rice genome encodes 96 APs, of which only a few have been functionally characterized. Here, the identification and characterization of a novel AP gene, OsAP65, which plays an indispensable role in pollen tube growth in rice, is reported. The T-DNA insertion line of OsAP65 caused severe segregation distortion. In the progeny derived from an individual heterozygous for the T-DNA insertion, the wild type and T-DNA-carrying heterozygote segregated at a ratio close to 1:1, while homozygotes of disrupted OsAP65 (OsAP65-/-) were not recovered. Reciprocal crosses between heterozygotes and wild-type plants demonstrated that the mutant alleles could not be transmitted through the male gamete. Examination of the anthers from heterozygous plants revealed that the mutant pollen matured normally, but did not germinate or elongate. OsAP65 was expressed in various tissues and the transcript level in heterozygous plants was about half of the amount measured in the wild-type plants. The subcellular localization showed that OsAP65 is a pre-vacuolar compartment (PVC) protein. These results indicated that OsAP65 was essential for rice pollen germination and tube growth.
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Combination of plant and insect eggs as food sources facilitates ovarian development in an omnivorous bug Apolygus lucorum (Hemiptera: Miridae).
J. Econ. Entomol.
PUBLISHED: 07-20-2013
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Diet nutrient is considered as an important regulatory factor for reproduction of insects. To understand the effect of different food sources on the reproductive physiology of Apolygus lucorum (Meyer-Dür), the ovarian development in adult females was investigated when they were fed on green beans (Gb), combination of green beans Phaseolus vulgaris L and Helicoverpa armigera eggs (GbHe), or H. armigera eggs (He). A female of A. lucorum has two ovaries, and each ovary contained seven yellowish ovarioles. Females fed on Gb or GbHe had larger ovaries and the ovarioles contained larger numbers of oocytes compared with those fed on He. Females in GeHe treatment has significantly higher number of follicles per ovary throughout the whole adult period compared with those in Gb or He treatment. Furthermore, the length of the best developed ovariole was affected by the diet type. The females fed on GbHe had the most developed ovarioles, with significantly longer ovarioles than those fed on Gb or He. A method was described to quantitatively score the degree of ovarian development in the current study. Similarly, the ovarian development scores were significantly higher for females in GbHe treatment than those in other two diet treatments. The ovarian development significantly delayed for females fed on He. Our results demonstrate that A. lucorum, as an omnivorous insect species, can acquire nutrients from both plant and animal origin food sources, and the combination of plants and animal food sources can significantly facilitate the ovary development of its females.
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Copper-catalyzed aerobic oxidative c?h functionalization of substituted pyridines: synthesis of imidazopyridine derivatives.
Chemistry
PUBLISHED: 07-14-2013
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A novel, efficient, and practical method for the synthesis of imidazopyridine derivatives has been developed through the copper-catalyzed aerobic oxidative C?H functionalization of substituted pyridines with N-(alkylidene)-4H-1,2,4-triazol-4-amines. The procedure occurs by cleavage of the N?N bond in the N-(alkylidene)-4H-1,2,4-triazol-4-amines and activation of an aryl C?H bond in the substituted pyridines. This is the first example of the preparation of imidazopyridine derivatives by using pyridines as the substrates by transition-metal-catalyzed C?H functionalization. This method should provide a novel and efficient strategy for the synthesis of other nitrogen heterocycles.
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A novel anti-sTn monoclonal antibody 3P9 Inhibits human xenografted colorectal carcinomas.
J. Immunother.
PUBLISHED: 06-29-2013
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The aim of this study is to raise tumor-suppressing monoclonal antibodies (mAbs) against colorectal carcinomas. Here, we generated a novel mAb 3P9, targeted a cancer-associated carbohydrate antigen sialyl-Tn (sTn), which showed significant inhibitory effect on proliferation and migration of sTn cells and tumor growth by inducing apoptosis. We also demonstrated that mAb 3P9 showed higher sensitivity and specificity in immunohistochemistry assay on colonic adenocarcinoma than the broadly used commercial anti-sTn antibody B72.3. These results provide the first evidence that mAb 3P9 has potential applications, not only for diagnosis but also for antibody-based tumor therapy.
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Copper-catalyzed annulation of amidines for quinazoline synthesis.
Chem. Commun. (Camb.)
PUBLISHED: 06-13-2013
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An efficient Cu-catalyzed synthesis of quinazolines via the C-N bond formation reactions between N-H bonds of amidines and C(sp(3))-H bonds adjacent to sulfur or nitrogen atoms in the commonly used solvents, such as DMSO, DMF, DMA, NMP or TMEDA, followed by intramolecular C-C bond formation reactions was developed for the first time.
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The influence of genetic polymorphisms in MDR1 gene on breast cancer risk factors in Chinese.
Med. Oncol.
PUBLISHED: 04-16-2013
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Breast cancer (BC) is the most common cancer among women in the world. The human multidrug resistance 1 gene (MDR1) is potentially an important gene influencing the susceptibility to breast cancer. This study aimed to assess the association of MDR1 genetic polymorphisms with the susceptibility to BC. Overall, 353 BC patients and 360 cancer-free controls were enrolled. The clinical characteristics were summarized by questionnaires. The c.1564A > T genetic polymorphism was genotyped using created restriction site-polymerase chain reaction method. We found that no significant differences in the genotypic and allelic frequencies between BC patients and cancer-free controls. Furthermore, the distribution of BC patients risk factors was not significantly different among AA, AT, and TT genotypes. Our findings indicate that the c.1564A > T genetic polymorphism is not significantly associated with the susceptibility to BC in Chinese Han populations.
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Baicalin plays an anti-inflammatory role through reducing nuclear factor-?B and p38 phosphorylation in S. aureus-induced mastitis.
Int. Immunopharmacol.
PUBLISHED: 03-04-2013
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Mastitis is an inflammatory disease caused by microbial infection. Staphylococcus aureus is the major etiological microorganism responsible for both clinical and subclinical mastitis in dairy cows. A mouse model of S. aureus mastitis is available. Baicalin is isolated from Scutellaria and is known to have anti-inflammatory properties. This study was designed to evaluate the effects of baicalin in S. aureus mastitis. In the present study, the mouse model was infected with S. aureus to cause mammary gland inflammation. Baicalin treatment was administered from 6h until 24h after infection. Baicalin significantly attenuated inflammatory cell infiltration and decreased levels of TNF-?, IL-?, and IL-6. Further studies revealed that baicalin downregulated phosphorylation of NF-?B and p38 in the mammary gland with S. aureus mastitis. Our results demonstrated that baicalin reduced the expression of the proinflammatory cytokines TNF-?, IL-?, and IL-6 by inhibiting NF-?B and p38 phosphorylation and mRNA expression.
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RP105 involved in activation of mouse macrophages via TLR2 and TLR4 signaling.
Mol. Cell. Biochem.
PUBLISHED: 03-02-2013
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RP105 is a member of the toll-like receptor family of proteins that transmits an activation signal in B cells, playing a role in regulation of B cell growth and death; in macrophages and dendritic cells, RP105 is a specific inhibitor of TLR4 signaling. RP105 is uniquely important for regulating TLR4-dependent signaling. It also proved that RP105 is closely related to TLR2 in macrophage activation by Mycobacterium tuberculosis lipoproteins. The aim of our study is to investigate the role of RP105 in mouse macrophages activation of TLR4 and TLR2 signaling by lipopolysaccharides (LPS) and Pam3CysSerLys4 (Pam3CSK4) alone or in combination, and the interaction between TLR2 and TLR4 signaling through RP105. Our results indicate that besides exhibiting negative regulation of TNF-? and IL12-p40 secretion in macrophage activated by LPS, RP105 is also involved in macrophages activation by Pam3CSK4 through TLR2 signaling and exhibited regulation to IL-10 and RANTES production by mouse peritoneal macrophage activated by Pam3CSK4. In macrophages activation by LPS and Pam3CSK4 in combination, TLR2 signaling can overcome RP105-mediated regulation of TLR4 signaling. Thus, our data demonstrate that not only TLR4 signaling, but also RP105 appears to be an essential accessory for immune responses through TLR2 signaling. The function of TLR2 and TLR4 in response to TLR ligands could be associated with each other by RP105. These results can help us understanding the unique role of RP105 in macrophages response to TLR ligands.
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Cloning, expression, and characterization of ?-mannanase from Bacillus subtilis MAFIC-S11 in Pichia pastoris.
Appl. Biochem. Biotechnol.
PUBLISHED: 02-18-2013
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The ?-mannanase gene (1,029 nucleotide) from Bacillus subtilis MAFIC-S11, encoding a polypeptide of 342 amino acids, was cloned and expressed in Pichia pastoris. To increase its expression, the ?-mannanase gene was optimized for codon usage (mannS) and fused downstream to a sequence-encoding modified ?-factor signal peptide. The expression level was improved by 2-fold. This recombinant enzyme (mannS) showed its highest activity of 24,600 U/mL after 144-h fermentation. The optimal temperature and pH of mannS were 50 °C and 6.0, respectively, and its specific activity was 3,706 U/mg. The kinetic parameters V max and K m were determined as 20,000 U/mg and 8 mg/mL, respectively, representing the highest ever expression level of ?-mannanase reported in P. pastoris. In addition, the enzyme exhibited much higher binding activity to chitin, chitosan, Avicel, and mannan. The superior catalytic properties of mannS suggested great potential as an effective additive in animal feed industry.
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