Cucurbit[7]uril-Mediated Supramolecular Bactericidal Nanoparticles: Their Assembly Process, Controlled Release, and Safe Treatment of Intractable Plant Bacterial Diseases.

A safe, biocompatible, and stimuli-responsive cucurbit[7]uril-mediated supramolecular bactericidal nanoparticle was fabricated by encapsulating a highly bioactive carbazole-decorated imidazolium salt (A1, EC50 = 0.647 µg/mL against phytopathogen Xanthomonas oryzae pv oryzae) into the host cucurbit[7]uril (CB[7]), thereby leading to self-assembled topographies from microsheets (A1) to nanospheroidal architectures (A1@CB[7]). The assembly behaviors were elucidated by acquired single-crystal structures, 1H NMR, ITC, and X-ray powder diffraction experiments. Complex A1@CB[7] displayed lower phytotoxicity and could efficiently switch on its potent antibacterial ability via introducing a simple competitor 1-adamantanamine hydrochloride (AD). In vivo antibacterial trials against rice bacterial blight revealed that A1@CB[7] could relieve the disease symptoms after being triggered by AD and provide a workable control efficiency of 42.6% at 100 µg/mL, which was superior to bismerthiazol (33.4%). These materials can provide a viable platform for fabricating diverse stimuli-responsive supramolecular bactericides for managing bacterial infections with improved safety.

Free Triiodothyronine Connected With Metabolic Changes in Patients With Coronary Artery Disease by Interacting With Other Functional Indicators.

This study aims to evaluate the association between free triiodothyronine (FT3) and outcomes of coronary artery disease (CAD) patients, as well as to assess the predictive power of FT3 and related functional markers from the perspective of potential mechanism. A total of 5104 CAD patients with an average follow-up of three years were enrolled into our study. Multivariate Cox regression was used to evaluate the associations between FT3, FT4 (free thyroxin), FT3/FT4 and death, MACE. We developed and validated an age, biomarker, and clinical history (ABC) model based on FT3 indicators to predict the prognosis of patients with CAD. In the multivariable Cox proportional hazards model, FT3 and FT3/FT4 were independent predictors of mortality (Adjusted HR = 0.624, 95% CI = 0.486-0.801; adjusted HR = 0.011, 95% CI = 0.002-0.07, respectively). Meanwhile, emerging markers pre-brain natriuretic peptide, fibrinogen, and albumin levels are significantly associated with low FT3 (p < 0.001). The new risk death score based on biomarkers can be used to well predict the outcomes of CAD patients (C index of 0.764, 95% CI = 0.731-0.797). Overall, our findings suggest that low levels of FT3 and FT3/FT4 are independent predictors of death and MACE risk in CAD patients. Besides, the prognostic model based on FT3 provides a useful tool for the death risk stratification of CAD patients.

Cytotoxic p-terphenyls from the deep-sea-derived Aspergillus candidus.

From the deep-sea-derived fungus Aspergillus candidus, one novel (1) and three known (2-4) p-terphenyl derivates were isolated. The structure of the new compound was established mainly on the basis of extensive analysis of 1D and 2D NMR data. All four isolates were tested for in vitro anti-food allergic and antitumor bioactivities. Compounds 3 and 4 showed potent antiproliferative effect against four cancer cells of Hela, Eca-109, Bel-7402, and PANC-1 with IC50 values ranging from 5.5 µM to 9.4 µM.

Expression of Bacillus thuringiensis toxin Cyt2Ba in the entomopathogenic fungus Beauveria bassiana increases its virulence towards Aedes mosquitoes.

BACKGROUND: The entomopathogenic fungus Beauveria bassiana has been widely used to kill mosquito larvae and adults in the laboratory and field. However, its slow action of killing has hampered its widespread application. In our study, the B. bassiana fungus was genetically modified to express the Bacillus thuringiensis (Bt) toxin Cyt2Ba to improve its efficacy in killing mosquitoes. METHODOLOGY/PRINCIPAL FINDINGS: The efficacy of the wild type (WT) of B. bassiana and a transgenic strain expressing Cyt2Ba toxin (Bb-Cyt2Ba) was evaluated against larval and adult Aedes mosquitoes (Aedes aegypti and Aedes albopictus) using insect bioassays. The Bb-Cyt2Ba displayed increased virulence against larval and adult Aedes mosquitoes compared with the WT: for Ae. aegypti adults, the median lethal time (LT50) was decreased by 33% at the concentration of 1× 108 conidia/ml, 19% at 1× 107 conidia/ml and 47% at 1× 106 conidia/ml. The LT50 for Ae. albopictus adults was reduced by 20%, 23% and 29% at the same concentrations, respectively. The LT50 for Ae. aegypti larvae was decreased by 42% at 1× 107 conidia/ml and 25% at 1× 106 conidia/ml, and that for Ae. albopictus larvae was reduced by 33% and 31% at the same concentrations, respectively. In addition, infection with Bb-Cyt2Ba resulted in a dramatic reduction in the fecundity of Aedes mosquitoes. CONCLUSIONS/SIGNIFICANCE: In conclusion, our study demonstrated that the virulence of B. bassiana against mosquitoes can be significantly improved by introducing the Bt toxin gene Cyt2Ba into the genome to express the exogenous toxin in the fungus. The transgenic strain Bb-Cyt2Ba significantly reduced the survival and fecundity of Ae. aegypti and Ae. albopictus compared with the WT strain, which suggested that this recombinant B. bassiana has great potential for use in mosquito control.

Cascade Reaction of Isatins with 1,1-Enediamines: Synthesis of Multisubstituted Quinoline-4-carboxamides.

A one-step methodology for the synthesis of multisubstituted quinoline-4-carboxamides was developed by simply refluxing a mixture of isatins 1 and various kinds of 1,1-enediamines 2-4 in a reaction catalyzed by NH2SO3H. As a result, a series of quinolone-4-carboxamides were produced through a novel cascade reaction mechanism. This reaction involved the formation of the quinoline ring accompanied by the formation of an amide bond in one step. Accordingly, this protocol is suitable for combinatorial and parallel syntheses of quinolone-4-carboxamide drugs or natural products.

Memory and threshold resistance switching in Ni/NiO core-shell nanowires.

We report on the first controlled alternation between memory and threshold resistance switching (RS) in single Ni/NiO core-shell nanowires by setting the compliance current (I(CC)) at room temperature. The memory RS is triggered by a high I(CC), while the threshold RS appears by setting a low I(CC), and the Reset process is achieved without setting a I(CC). In combination with first-principles calculations, the physical mechanisms for the memory and threshold RS are fully discussed and attributed to the formation of an oxygen vacancy (Vo) chain conductive filament and the electrical field induced breakdown without forming a conductive filament, respectively. Migration of oxygen vacancies can be activated by appropriate Joule heating, and it is energetically favorable to form conductive chains rather than random distributions due to the Vo-Vo interaction, which results in the nonvolatile switching from the off- to the on-state. For the Reset process, large Joule heating reorders the oxygen vacancies by breaking the Vo-Vo interactions and thus rupturing the conductive filaments, which are responsible for the switching from on- to off-states. This deeper understanding of the driving mechanisms responsible for the threshold and memory RS provides guidelines for the scaling, reliability, and reproducibility of NiO-based nonvolatile memory devices.

[Concentrations and influence factors of polycyclic aromatic hydrocarbons in leaves of dominant species in the Pearl River Delta, South China].

Concentrations of PAHs in leaves of six dominant species in the Pearl River Delta of South China were determined with gas chromatography and mass spectrometry (GC-MS), and synchronously leaf-lipid contents, leaf areas, specific leaf areas (SLA) were measured. The characters of PAHs abundance and influence factors on them were investigated. The results show that concentrations of PAHs in pine needles are higher than those in broad-leaves remarkably, and the highest value (1034.7 ng x g(-1) in Pinus massoniana) is fivefold of the lowest (199.7 ng x g(-1) in Schima superba) . Flu, Phe, Fluo, Pyr, Chr are the main components of sigma PAHs, and the concentrations of 3-ring and 4-ring PAHs exceed 80% of the total PAHs. Significant positive correlations between the components and sigma PAHs were also detected. The PAHs contents by per lipid could reduce inter-species variance obviously, and the diversity is no more than two times (6.8 ng x mg(-1) and 2.7 ng x mg(-1), respectively). Adversely, the PAHs contents by per cm2 magnify inter-species variance, and the highest value (15.3 ng x cm(-2)) ascends to eight times of the lowest (1.9 ng x cm(-2)). Furthermore, significant positive correlation between PAHs and leaf-lipid contents was identified, as well as negative correlation between PAHs and specific leaf areas. All of these indicate that leaf-lipid contents and specific leaf areas are two significant factors which influenced PAHs contents in leaves.