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1.
The nematicidal activity of two cassia, Cinnamomum cassia, oils (Especial and true), four cinnamon, Cinnamomum zey-lanicum, oils (technical, #500, bark and green leaf), and their compounds (e.g., trans-cinnamaldehyde and trans-cinnamic acid) toward adult Bursaphelenchus xylophilus was examined by a direct contact bioassay. Results were compared with those of 34 related compounds. As judged by 24-hour LC50 values, two cassia oils (0.084–0.085 mg/ml) and four cinnamon oils (0.064–0.113 mg/ml) were toxic toward adult B. xylophilus. Of 45 test compounds, trans-cinnamaldehyde (0.061 mg/ml) was the most active nematicide, followed by ethyl cinnamate, α-methyl-trans-cinnamaldehyde, methyl cinnamate and allyl cinnamate (0.114–0.195 mg/ml). Potent nematicidal activity was also observed with 4-methoxycinnamonitrile, trans-4-methoxycinnamaldehyde, trans-2-methoxy-cinnamaldehyde, ethyl α-cyanocinnamate, cinnamonitrile and cinnamyl bromide (0.224–0.502 mg/ml). Structure-activity relationships indicate that structural characteristics, such as types of functional groups, saturation and carbon skeleton, appear to play a role in determining the toxicities to adult B. xylophilus. Cassia and cinnamon oils and test compounds described merit further study as potential nematicides or leads for the control of pine wilt disease caused by B. xylophilus.  相似文献   

2.
Microbial biotransformation of monoterpenes results in the formation of many valuable compounds. Many microorganisms can be used to carry out extremely specific conversions using substrates of low commercial value. Absidia corulea MTCC 1335 was examined for its ability to transform α-Pinene enantiomers. The substrates (−)-α-Pinene and (+)-α-Pinene converted to α-terpineol and isoterpineol, were detected in gas chromatographic analysis. The Biotransformation kinetics of the oxidized products were analysed using GC–MS. With both the substrates the products formed were similar and not much difference in the rate of transformation was observed, suggesting no enantioselectivity of organism towards the substrate.  相似文献   

3.
《Journal of Asia》2006,9(2):173-178
The nematicidal activity and poisoning symptoms of 88 plant essential oils against Bursaphelenchus xylophilus were examined by an immersion bioassay. Results were compared with those of three trunk-injection nematicides: fenitrithion, levamisol hydrochloride, and morantel tartrate. As judged by 24 h LC50 values, cinnamon bark oil (0.12 mg/ml) was the most effective nematicide, followed by coriander herb oil (0.14 mg/ml). Potent nematicidal activity was also observed with lemongrass, oregano, thyme red, and clove bud oils (LC50, 0.57-0.88 mg/ml). Fenitrothion was ineffective (LC50, > 10 mg/ml). In typical poisoning symptoms in B. xylophilus, these essential oils exerted rapid nematicidal action and the nematodes killed usually showed an extended shape, whereas levamisole hydrochloride and morantel tartrate usually exhibited semicircular and coiling shapes, respectively. The essential oils described merit further study as botanical nematicides for the control of pine wilt disease caused by B. xylophilus.  相似文献   

4.
A protocol for in vitro propagation was developed for Viola pilosa, a plant of immense medicinal value. To start with in vitro propagation, the sterilized explants (buds) were cultured on MS basal medium supplemented with various concentrations of growth regulators. One of the medium compositions MS basal + 0.5 mg/l BA + 0.5 mg/l TDZ + 0.5 mg/l GA3 gave best results for in vitro shoot bud establishment. Although the problem of shoot vitrification occurred on this medium but this was overcome by transferring the vitrified shoots on MS medium supplemented with 1 mg/l BA and 0.25 mg/l Kn. The same medium was found to be the best medium for further in vitro shoot multiplication. 100 % root induction from in vitro grown shoots was obtained on half strength MS medium supplemented with 1 mg/l IBA. In vitro formed plantlets were hardened and transferred to soil with 83 % survival. Additionally, conservation of in vitro multiplying shoots was also attempted using two different approaches namely slowing down the growth at low temperature and cryopreservation following vitrification. At low temperature retrieval rate was better at 10 °C than at 4 °C after conservation of in vitro multiplying shoots. In cryopreservation–vitrification studies, the vitrified shoot buds gave maximum retrieval of 41.66 % when they were precooled at 4 °C, while only 16.66 % vitrified shoots were retrieved from those precooled at 10 °C. Genetic stability of the in vitro grown plants was analysed by RAPD and ISSR markers which indicated no somaclonal variation among in vitro grown plants demonstrating the feasibility of using the protocol without any adverse genetical effects.  相似文献   

5.
Diabetes is one of the most prevalent chronic diseases globally. In this study, major polyphenols (17.35 ± 0.93–36.66 ± 2.01 mg/g) and minor fucoxanthin (non detected 15.12 ± 0.09 mg/g) were isolated from water, ethanol, and acetone extracts (WES, EES, and AES, respectively) of Sargassum hemiphyllum. Inhibition of α-amylase, α-glucosidase, sucrose, and maltase activities and stimulation of insulin secretion was greater with AES than with WES or EES and correlated with polyphenol and fucoxanthin concentrations in extracts. Moreover, 250 μg/ml EES and AES significantly increased insulin secretion in the presence of 25 mg/ml glibenclamide to higher levels than those obtained with 50 mg/ml glibenclamide. None of the extracts exhibited cytotoxicity, exacerbated the side effects of glibenclamide, or inhibited glibenclamide-induced insulin secretion. These results suggested that the S. hemiphyllum extracts WES, EES, and AES could be used as pharmaceuticals and functional foods to reduce dosages of synthetic diabetes drugs.  相似文献   

6.
7.
Niu H  Zhao L  Lu M  Zhang S  Sun J 《PloS one》2012,7(2):e31716
The pinewood nematode (PWN) Bursaphelenchus xylophilus, vectored primarily by the sawyer beetle, Monochamus alternatus, is an important invasive pest and causal agent of pine wilt disease of Chinese Masson pine, Pinus massoniana. Previous work demonstrated that the ratios and concentrations of α-pinene∶β-pinene differed between healthy trees and those trees containing blue-stain fungus (and M. alternatus pupae). However, the potential influence of the altered monoterpene ratios and concentrations on PWN and associated fungi remained unknown. Our current results show that low concentrations of the monoterpenes within petri dishes reduced PWN propagation, whereas the highest concentration of the monoterpenes increased PWN propagation. The propagation rate of PWN treated with the monoterpene ratio representative of blue-stain infected pine (α-pinene∶β-pinene = 1∶0.8, 137.6 mg/ml) was significantly higher than that (α-pinene∶β-pinene = 1∶0.1, 137.6 mg/ml) representative of healthy pines or those damaged by M. alternatus feeding, but without blue stain. Furthermore, inhibition of mycelial growth of associated fungi increased with the concentration of the monoterpenes α-pinene and β-pinene. Additionally, higher levels of β-pinene (α-pinene∶β-pinene = 1∶0.8) resulted in greater inhibition of the growth of the associated fungi Sporothrix sp.2 and Ophiostoma ips strains, but had no significant effects on the growth of Sporothrix sp.1, which is the best food resource for PWN. These results suggest that host monoterpenes generally reduce the reproduction of PWN. However, PWN utilizes high monoterpene concentrations and native blue-stain fungus Sporothrix sp.1 to improve its own propagation and overcome host resistance, which may provide clues to understanding the ecological mechanisms of PWN''s successful invasion.  相似文献   

8.
In this study, the antioxidant, antimicrobial, genotoxic and anticancer activities of Cetraria islandica methanol extract were determined by using free radical and superoxide anion scavenging activity, reducing power, determination of total phenolic compounds and flavonoid contents, broth microdilution minimal inhibitory concentration against five bacterial and five fungal species, cytokinesis block micronucleus (MN) assay on peripheral blood lymphocytes (PBLs) and the microculture tetrazolium test on FemX (human melanoma) and LS174 (human colon carcinoma) cell lines. As a result of the study, we found that C. islandica methanol extract exhibited moderate free-radical-scavenging activity with IC50 values 678.38 μg/ml. Moreover, the tested extract had effective reducing power and superoxide anion radical scavenging. The minimal inhibitory concentration values against the tested microorganisms ranged from 0.312 to 5 mg/ml. The extract increased MN frequency in a dose dependent manner, but it was significant in higher tested concentrations (50, 100 and 200 μg/ml). No significant differences were observed between NDI values in all treatments and untreated PBLs. In addition, the tested extract had strong anticancer activity towards both cell lines with IC50 values of 22.68 and 33.74 μg/ml. It can be concluded that the tested extract exhibited a certain level of in vitro antioxidant, antimicrobial, genotoxic and anticancer activities.  相似文献   

9.
A new HPLC method was developed to separate linear from β(1–6)-branched β(1–3)-glucooligosaccharides. This methodology has permitted the isolation of the first fungal β(1–6)/β(1–3)-glucan branching transglycosidase using a cell wall autolysate of Aspergillus fumigatus (Af). The encoding gene, AfBGT2 is an ortholog of AfBGT1, another transglycosidase of A. fumigatus previously analyzed (Mouyna, I., Hartland, R. P., Fontaine, T., Diaquin, M., Simenel, C., Delepierre, M., Henrissat, B., and Latgé, J. P. (1998) Microbiology 144, 3171–3180). Both enzymes release laminaribiose from the reducing end of a β(1–3)-linked oligosaccharide and transfer the remaining chain to another molecule of the original substrate. The AfBgt1p transfer occurs at C-6 of the non-reducing end group of the acceptor, creating a kinked β(1–3;1–6) linear molecule. The AfBgt2p transfer takes place at the C-6 of an internal group of the acceptor, resulting in a β(1–3)-linked product with a β(1–6)-linked side branch. The single Afbgt2 mutant and the double Afbgt1/Afbgt2 mutant in A. fumigatus did not display any cell wall phenotype showing that these activities were not responsible for the construction of the branched β(1–3)-glucans of the cell wall.  相似文献   

10.
Plants are still to be explored for new anti-cancer compounds because overall success in cancer treatment is still not satisfactory. As a new possible source for such compounds, the lichens are recently taking a great attention. We, therefore, explored both the genotoxic and anti-growth properties of lichen species Parmelia sulcata Taylor. The chemical composition of P. sulcata was analyzed with comprehensive gas chromatography–time of flight mass spectrometry. Anti-growth effect was tested in human breast cancer cell lines (MCF-7 and MDA-MB-231) by the MTT and ATP viability assays, while the genotoxic activity was studied by assays for micronucleus, chromosomal aberration and DNA fragmentation in human lymphocytes culture. Cell death modes (apoptosis/necrosis) were morphologically assessed. P. sulcata inhibited the growth in a dose-dependent manner up to a dose of 100 μg/ml and induced caspase-independent apoptosis. It also showed genotoxic activity at doses (>125 μg/ml) higher than that required for apoptosis. These results suggest that P. sulcata may induce caspase-independent apoptotic cell death at lower doses, while it may be genotoxic at relatively higher doses.  相似文献   

11.
N-Glycans of the Na,K-ATPase β1 subunit are important for intercellular adhesion in epithelia, suggesting that epithelial junctions depend on N-glycan-mediated interactions between the β1 subunits of neighboring cells. The level of co-immunoprecipitation of the endogenous β1 subunit with various YFP-linked β1 subunits expressed in Madin-Darby canine kidney cells was used to assess β11 interactions. The amount of co-precipitated endogenous dog β1 was greater with dog YFP-β1 than with rat YFP-β1, showing that amino acid-mediated interactions are important for β11 binding. Co-precipitation of β1 was also less with the unglycosylated YFP-β1 than with glycosylated YFP-β1, indicating a role for N-glycans. Mixing cells expressing dog YFP-β1 with non-transfected cells increased the amount of co-precipitated β1, confirming the presence of intercellular (YFP-β1)-β1 complexes. Accordingly, disruption of intercellular junctions decreased the amount of co-precipitated β1 subunits. The decrease in β1 co-precipitation both with rat YFP-β1 and unglycosylated YFP-β1 was associated with decreased detergent stability of junctional proteins and increased paracellular permeability. Reducing N-glycan branching by specific inhibitors increased (YFP-β1)-β1 co-precipitation and strengthened intercellular junctions. Therefore, interactions between the β1 subunits of neighboring cells maintain integrity of intercellular junctions, and alterations in the β1 subunit N-glycan structure can regulate stability and tightness of intercellular junctions.  相似文献   

12.
Various NGR-containing peptides have been exploited for targeted delivery of drugs to CD13-positive tumor neovasculature. Recent studies have shown that compounds containing this motif can rapidly deamidate and generate isoaspartate-glycine-arginine (isoDGR), a ligand of αvβ3-integrin that can be also exploited for drug delivery to tumors. We have investigated the role of NGR and isoDGR peptide scaffolds on their biochemical and biological properties. Peptides containing the cyclic CNGRC sequence could bind CD13-positive endothelial cells more efficiently than those containing linear GNGRG. Peptide degradation studies showed that cyclic peptides mostly undergo NGR-to-isoDGR transition and CD13/integrin switching, whereas linear peptides mainly undergo degradation reactions involving the α-amino group, which generate non-functional six/seven-membered ring compounds, unable to bind αvβ3, and small amount of isoDGR. Structure-activity studies showed that cyclic isoDGR could bind αvβ3 with an affinity >100-fold higher than that of linear isoDGR and inhibited endothelial cell adhesion and tumor growth more efficiently. Cyclic isoDGR could also bind other integrins (αvβ5, αvβ6, αvβ8, and α5β1), although with 10–100-fold lower affinity. Peptide linearization caused loss of affinity for all integrins and loss of specificity, whereas α-amino group acetylation increased the affinity for all tested integrins, but caused loss of specificity. These results highlight the critical role of molecular scaffold on the biological properties of NGR/isoDGR peptides. These findings may have important implications for the design and development of anticancer drugs or tumor neovasculature-imaging compounds, and for the potential function of different NGR/isoDGR sites in natural proteins.  相似文献   

13.
A field strain of Haemonchus contortus isolated from sheep at Armidale N.S.W., was found to be resistant to thiabendazole with approximately 20 per cent of the worms surviving a 50 mg/kg dose. The isolate was selected over six generations for resistance to 50 mg/kg thiabendazole. After this time, selection on one line was continued at 50 mg/kg thiabendazole and selection on a second line was extended to include 8·8 mg/kg morantel tartrate. A drug tolerance assay on the third generation of the thiabendazole-morantel tartrate selected line showed the ld5o to be 5·3 mg/kg and the ld95 to be 18 mg/kg morantel tartrate; the reported ld50 and ld95 for non-resistant strains of H. contortus to morantel tartrate are 2·5 mg/kg and 8 mg/kg respectively. In the fourth generation the thiabendazole and the thiabendazole-morantel tartrate selected lines together with a recently isolated field strain were assayed for resistance to thiabendazole, morantel tartrate and levamisole. The results indicated that the resistance to thiabendazole was probably due to a single gene. Both selected lines were more resistant to thiabendazole than the field strain. The thiabendazole-morantel tartrate selected line was more resistant to morantel tartrate than either of the other two. Resistance to morantel tartrate appeared to be polygenic in nature and due to increased vigour. The lowest dose of levamisole (1·6 mg/kg) killed more than 95 per cent of all strains of worms. There was no significant increase in effectiveness at higher dose rates indicating that surviving worms were resistant to the drug.  相似文献   

14.
Avermectins are macrocyclic lactones produced by Streptomyces avermitilis. Abamectin is a blend of B1a and B1b avermectins that is being used as a seed treatment to control plant-parasitic nematodes on cotton and some vegetable crops. No LD50 values, data on nematode recovery following brief exposure, or effects of sublethal concentrations on infectivity of the plant-parasitic nematodes Meloidogyne incognita or Rotylenchulus reniformis are available. Using an assay of nematode mobility, LD50 values of 1.56 μg/ml and 32.9 μg/ml were calculated based on 2 hr exposure for M. incognita and R. reniformis, respectively. There was no recovery of either nematode after exposure for 1 hr. Mortality of M. incognita continued to increase following a 1 hr exposure, whereas R. reniformis mortality remained unchanged at 24 hr after the nematodes were removed from the abamectin solution. Sublethal concentrations of 1.56 to 0.39 μg/ml for M. incognita and 32.9 to 8.2 μg/ml for R. reniformis reduced infectivity of each nematode on tomato roots. The toxicity of abamectin to these nematodes was comparable to that of aldicarb.  相似文献   

15.
16.
Le Jambre I. F., Southcott W. H. and Dash K. M. 1977. Resistance of selected lines of Ostertagia circumcincta to thiabendazole, morantel tartrate and levamisole. International Journal for Parasitology7: 473–479. A strain of Ostertagia circumcincta was isolated from a field in which all sheep had been treated in sequence every 7–10 days from September 1970 to January 1974 with either thiabendazole, morantel tartrate or levamisole. Thiabendazole had not been used after the first 15 months. The LD95 for this strain was 88 mg/kg thiabendazole, 6.9 mg/kg morantel tartrate and 5-4 mg/kg levamisole.Another strain of O. circumcincta isolated from an area where anthelmintics had been used much less frequently was divided into four lines for exposure to selection in the laboratory. The first line was selected with 50 mg/kg thiabendazole, the second with 5 mg/kg morantel tartrate, and the third with 3.2 mg/kg levamisole; the fourth line was not selected for drug resistance. After eight generations the three lines selected with thiabendazole, morantel tartrate and levamisole had (Spld)(in95) of > 200, 5.7 and 6.2 mg/kg for the selecting drugs respectively, compared with corresponding values of 20, 2.9, and 1.8 in the unselected line. That is, the field strain had about the same levels of resistance to morantel tartrate and levamisole as the respective laboratory strains selected with these individual drugs. However, the field strain, which had been exposed to thiabendazole for only 15 months, was less resistant to thiabendazole than the laboratory strain selected with this drug. These results show that giving of several drugs in sequence cannot be relied upon to prevent the development of resistance to the individual drugs.The dose responses of adult worms showed low, but significant resistances to morantel tartrate and levamisole and a relatively high resistance to thiabendazole. Levamisole was found to select for inhibition of development with approx. 8.0% of the inhibited larvae showing no dose response above 1.6 mg/kg. Levamisole was also associated with an increase from 0.1 % to 9.0% in the O. trifurcata component of an Ostertagia population.  相似文献   

17.
18.
19.
We have previously demonstrated that interrupting the protein–protein interaction (PPI) of β-tubulin:chaperonin-containing TCP-1β (CCT-β) induces the selective killing of multidrug-resistant cancer cells due to CCT-β overexpression. However, the molecular mechanism has not yet been identified. In this study, we found that CCT-β interacts with a myriad of intracellular proteins involved in the cellular functions of the endoplasmic reticulum (ER), mitochondria, cytoskeleton, proteasome and apoptosome. Our data show that the targeted cells activate both the heat-shock protein 90 (Hsp90)-associated protein ubiquitination/degradation pathway to eliminate misfolded proteins in the cytoplasm and the valosin-containing protein (VCP)-centered ER-associated protein degradation pathway to reduce the excessive levels of unfolded polypeptides from the ER, thereby mitigating ER stress, at the onset of β-tubulin:CCT-β complex disruption. Once ER stress is expanded, ER stress-associated apoptotic signaling is enforced, as exhibited by cellular vacuolization and intracellular Ca2+ release. Furthermore, the elevated intracellular Ca2+ levels resulting from capacitative Ca2+ entry augments apoptotic signaling by provoking mitochondrial perturbation and caspase overactivation in the targeted cells. These findings not only provide a detailed picture of the apoptotic signaling cascades evoked by targeting the β-tubulin:CCT-β complex but also demonstrate a strategy to combat malignancies with chemoresistance to Hsp90- and VCP-related anticancer agents.  相似文献   

20.

Objective

to assess the levels and determinants of interleukin (IL)-1β, IL-6, tumour necrosis factor (TNF)-α and C-reactive protein (CRP) in a healthy Caucasian population.

Methods

population sample of 2884 men and 3201 women aged 35 to 75. IL-1β, IL-6 and TNF-α were assessed by a multiplexed particle-based flow cytometric assay and CRP by an immunometric assay.

Results

Spearman rank correlations between duplicate cytokine measurements (N = 80) ranged between 0.89 and 0.96; intra-class correlation coefficients ranged between 0.94 and 0.97, indicating good reproducibility. Among the 6085 participants, 2289 (37.6%), 451 (7.4%) and 43 (0.7%) had IL-1β, IL-6 and TNF-α levels below detection limits, respectively. Median (interquartile range) for participants with detectable values were 1.17 (0.48–3.90) pg/ml for IL-1β; 1.47 (0.71–3.53) pg/ml for IL-6; 2.89 (1.82–4.53) pg/ml for TNF-α and 1.3 (0.6–2.7) ng/ml for CRP. On multivariate analysis, greater age was the only factor inversely associated with IL-1β levels. Male sex, increased BMI and smoking were associated with greater IL-6 levels, while no relationship was found for age and leisure-time PA. Male sex, greater age, increased BMI and current smoking were associated with greater TNF-α levels, while no relationship was found with leisure-time PA. CRP levels were positively related to age, BMI and smoking, and inversely to male sex and physical activity.

Conclusion

Population-based levels of several cytokines were established. Increased age and BMI, and to a lesser degree sex and smoking, significantly and differentially impact cytokine levels, while leisure-time physical activity has little effect.  相似文献   

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