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51.
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This study led to the discovery of four putative entomopathogenic fungi of armoured scale insects on citrus trees in coastal New South Wales. Two of these species belong in Podonectria as P. coccicola (Ellis & Everh.) Petch (syn. Tetracrium coccicola (Höhn.) Ellis & Everh.) and P. novae-zelandiae Dingley. Members of this genus are grown in culture for the first time. Formerly placed in the Pleosporales, Tubeufiaceae, or more recently in the Tubeufiales, these species are herein placed in the new family Podonectriaceae fam. nov., Pleosporales. Another species is placed in the Hypocreales, Bionectriaceae as Clonostachys coccicola (J.A. Stev.) H.T. Dao comb. nov. (basionym Tubercularia coccicola J.A. Stev., syn. Nectria tuberculariae Petch). The fourth species is Myriangium citri Henn. (Myriangiales, Myriangiaceae). Each fungal species is characterized and the phylogenetic placement confirmed by molecular analyses of the ITS and 28 s rDNA regions. In addition, their biology is noted, including location of the fungi within tree canopies.  相似文献   
53.
The leucocyte-specific phosphatase CD45 is present in two main isoforms: the large CD45RA and the short CD45RO. We have recently shown that distinctive expression of these isoforms distinguishes natural killer (NK) populations. For example, co-expression of both isoforms identifies in vivo the anti tumor NK cells in hematological cancer patients. Here we show that low CD45 expression associates with less mature, CD56bright, NK cells. Most NK cells in healthy human donors are CD45RA+CD45RO-. The CD45RA-RO+ phenotype, CD45RO cells, is extremely uncommon in B or NK cells, in contrast to T cells. However, healthy donors possess CD45RAdimRO- (CD45RAdim cells), which show immature markers and are largely expanded in hematopoietic stem cell transplant patients. Blood borne cancer patients also have more CD45RAdim cells that carry several features of immature NK cells. However, and in opposition to their association to NK cell progenitors, they do not proliferate and show low expression of the transferrin receptor protein 1/CD71, suggesting low metabolic activity. Moreover, CD45RAdim cells properly respond to in vitro encounter with target cells by degranulating or gaining CD69 expression. In summary, they are quiescent NK cells, with low metabolic status that can, however, respond after encounter with target cells.  相似文献   
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The aim of this study is to search for soluble epoxide hydrolase (sEH) inhibitors from natural plants, bioassay-guided fractionation of lipophilic n-hexane and chloroform layers of an extract of the aerial parts of Glycosmis stenocarpa led to the isolation of 12 compounds (112) including murrayafoline-A (1), isomahanine (2), bisisomahanine (3), saropeptate (4), (24?S)-ergost-4-en-3,6-dione (5), stigmasta-4-en-3,6-dion (6), stigmast-4-en-3-one (7), β-sitosterol (8), 24-methylpollinastanol (9), trans-phytol (10), neosarmentol III (11) and (+)-epiloliolide (12). Their structures were elucidated on the basis of spectroscopic data. Among them, neosarmentol III (11) was isolated from nature for the first time. All the isolated compounds were evaluated for their inhibitory activity against sEH. Among isolated carbazole-type compounds, isomahanine (2) and bisisomahanine (3) were identified as a potent inhibitor of sEH, with IC50 values of 22.5?±?1.7 and 7.7?±?1.2?µM, respectively. Moreover, the inhibitory action of 2 and 3 represented mixed-type enzyme inhibition.  相似文献   
56.
The concept of drug repositioning has recently received considerable attention in the field of oncology. In the present study, we propose that paroxetine can be used as a potent anticancer drug. Paroxetine, one of the selective serotonin reuptake inhibitors (SSRIs), has been widely prescribed for the treatment of depression and anxiety disorders. Recently, SSRIs have been reported to have anticancer activity in various types of cancer cells; however, the underlying mechanisms of their action are not yet known. In this study, we investigated the potential anticancer effect of paroxetine in human colorectal cancer cells, HCT116 and HT‐29. Treatment with paroxetine reduced cell viability, which was associated with marked increase in apoptosis, in both the cell lines. Also, paroxetine effectively inhibited colony formation and 3D spheroid formation. We speculated that the mode of action of paroxetine might be through the inhibition of two major receptor tyrosine kinases – MET and ERBB3 – leading to the suppression of AKT, ERK and p38 activation and induction of JNK and caspase‐3 pathways. Moreover, in vivo experiments revealed that treatment of athymic nude mice bearing HT‐29 cells with paroxetine remarkably suppressed tumour growth. In conclusion, paroxetine is a potential therapeutic option for patients with colorectal cancer.  相似文献   
57.
Plasmonics - Since the metamaterial perfect absorber (MPA) is composed of electromagnetic resonance structures, the main operational mechanism of the MPA is electromagnetic resonance. In this work,...  相似文献   
58.

The cooperation of Bacillus subtilis strain DKT and Comamonas testosteroni KT5 was investigated for biofilm development and toluenes and chlorobenzenes degradation. Bacillus subtilis strain DKT and C. testosteroni KT5 were co-cultured in liquid media with toluenes and chlorobenzenes to determine the degradation of these substrates and formation of dual-species biofilm used for the degradation process. Bacillus subtilis strain DKT utilized benzene, mono- and dichlorinated benzenes as carbon and energy sources. The catabolism of chlorobenzenes was via hydroxylation, in which chlorine atoms were replaced by hydroxyl groups to form catechol, followed by ring fission via the ortho-cleavage pathway. The investigation of the dual-species biofilm composed of B. subtilis DKT and C. testosteroni KT5 (a toluene and chlorotoluene-degrading isolate with low biofilm formation) showed that B. subtilis DKT synergistically promoted C. testosteroni KT5 to develop biofilm. The bacterial growth in dual-species biofilm overcame the inhibitory effects caused by monochlorobenzene and 2-chlorotoluene. Moreover, the dual-species biofilm showed effective degradability toward the mixture of these substrates. This study provides knowledge about the commensal relationships in a dual-culture biofilm for designing multispecies biofilms applied for the biodegradation of toxic organic substrates that cannot be metabolized by single-organism biofilms.

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59.
Susceptibility of Asian corn borer (ACB), Ostrinia furnacalis (Guenée) to Bacillus thuringiensis (Bt) Cry1Ab protein was studied between 2015 and 2016 with 11 ACB populations, collected from various geographical regions in Vietnam. A concentration range of Cry1Ab from 0.20 to 26.10 ng/cm2 of diet was evaluated against F1 ACB neonates using diet surface-overlay bioassays. Mortality data was recorded daily until seven days after infestation. Growth inhibition was recorded at the end of seven days. The median lethal concentration (LC50) varied ≈3-fold among the different populations, ranging from 0.58 to 1.83 ng/cm2 of diet with an overall mean of 0.86 ng/cm2 of diet. Even the lowest concentration of 0.20 ng/cm2 caused 73.53% growth inhibition. >90% growth inhibition was achieved at 0.82 ng/cm2 or higher concentrations. The results reflect natural variation in Bt susceptibility among ACB populations rather than variation caused by prior exposure to selection pressures. LC99 value (17.26 ng/cm2) was generated by pooling mortality data across different populations. The upper fiducial limit of LC99 (24.38 ng/cm2) could be a potential diagnostic dose for future resistance monitoring programs. The findings from this study suggest that ACB populations in Vietnam are highly susceptible to Cry1Ab protein. This is the first report of Cry1Ab susceptibility of different ACB populations in Vietnam and will serve as a baseline for future resistance monitoring work.  相似文献   
60.
Russian Journal of Bioorganic Chemistry - The regioselective synthesis of betulin 3,28-bis- and 28-monoacylates (nicotinate and isonicotinates) as well as of 3β-hemisuccinyl dipterocarpol was...  相似文献   
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