Cancer has become a common disease that seriously endangers human health and life. Up to now, the essential treatment method has been drug therapy, and drug delivery plays an important role in cancer ...therapy. To improve the efficiency of drug therapy, researchers are committed to improving drug delivery methods to enhance drug pharmacokinetics and cancer accumulation. Supramolecular coordination complexes (SCCs) with well-defined shapes and sizes are formed through the coordination between diverse functional organic ligands and metal ions, and they have emerged as potential components in drug delivery and cancer therapy. In particular, micelles or vesicles with the required biocompatibility and stability are synthesized using SCC-containing polymeric systems to develop novel carriers for drug delivery that possess combined properties and extended system tunability. In this study, the research status of SCC-containing polymeric systems as drug carriers and adjuvants for cancer treatment is reviewed, and a special focus is given to their design and preparation.
Supramolecular polymers based on supramolecular coordination complexes (SCCs) have received extensive attention because of their good stimulus responsiveness, processability and other properties. ...Herein, we report metallacycle-crosslinked supramolecular polymers via amino–yne click reaction, which were employed as well-performing elastomer materials. The supramolecular polymers cross-linked by the metallacycle not only maintained the aggregation induced emission (AIE) properties of the metallacycle, which were used to detect nitroaromatic explosives, but also had enhanced mechanical strength and toughness and exhibited elastomeric properties. This study provides a feasible strategy for the preparation of metallacycle-based supramolecular polymers with better mechanical properties.
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The substrate pH directly affects nutrient availability in the rhizosphere and nutrient uptake by plants. Macronutrients such as nitrogen, potassium, calcium, magnesium, and sulfur are highly ...available at pH 6.0-6.5, while micronutrients become less available at higher, alkaline pH (pH > 7.0). Recent research has indicated that low pHs can enhance nutrient uptake and improve sweet orange (
) tree health. We designed a study to understand the influence of a wide range of substrate pH values on plant size and biomass, nutrient availability, leaf gas exchange, and rhizosphere microbiome of grapefruit (
) affected by Huanglongbing (HLB). Two-year-old "Ray Ruby" grapefruit plants grafted on sour orange (
) rootstock were cultivated indoors in 10-cm wide × 40-cm tall pots with peat:perlite commercial substrate (80:20 v/v). We tested two disease statuses HLB-free or healthy (negative, HLB-) and HLB-affected (positive, HLB+) and six substrate pH values (4, 5, 6, 7, 8, 9) in a 2 × 6 factorial arranged on a complete randomized design with four replications. The canopy volume of HLB+ plants was 20% lower than healthy plants, with pHs 7 and 9 resulting in 44% less canopy volume. The root and shoot ratio of dry weight was 25.8% lower in HLB+ than in healthy plants. Poor root growth and a decrease in fibrous roots were found, especially in pH 5 and 6 treatments in HLB+ plants (
< 0.0001). The disease status and the substrate pHs influenced the leaf nutrient concentration (
< 0.05). High substrate pH affects nutrient availability for root uptake, influencing the nutrient balance throughout the plant system. pH values did not affect plant photosynthesis, indicating that pH does not recover HLB+ plants to the photosynthetic levels of healthy plants-even though high pH positively influenced internal CO
. There were collectively over 200 rhizobacterial identified by the 16S rRNA gene sequencing in individual phylogenetic trees. Most rhizobacteria reads were identified in pH 9. Our results indicated no effect of substrate pHs on the plant disease status induced by enhanced nutrient uptake.
Citrus Huanglongbing (HLB) is a serious disease for the citrus industry. Earlier studies showed that ampicillin (Amp) can reduce titers of the pathogen which causes HLB and the bacteria Candidatus ...Liberibacter asiaticus (CLas) in HLB-affected citrus. CLas has not yet been cultured, so the mechanisms of Amp against CLas are unclear. Some chemicals were demonstrated to trigger citrus defense systems against CLas. Therefore, we hypothesize that Amp may induce citrus defenses against CLas. Here we applied three nano-formulations of varying droplet sizes to HLB-affected citrus to achieve different accumulated concentrations of Amp (high, medium, low) in the plants. We then used RNA-seq to analyze induction of gene expression of citrus defense systems against CLas in response to different concentrations of Amp. The results indicated that at all accumulated concentrations of Amp can significantly suppress CLas titer and mitigate HLB symptoms. Transcriptomic analyses showed that Amp treatment induced expression of heat shock proteins (Hsps) in HLB-affected citrus, and these Hsps were significantly related to several defense genes encoding R proteins, transcription factors, splicing factors, RNA-binding proteins, RNA-dependent RNA polymerase, Gibberellic acid methyltransferase 2, L-ascorbate peroxidase 2, and ferruginol synthase that confer tolerance to CLas in citrus plants. Taken together, these results suggest that Amp treatment of citrus plants can trigger expression of Hsps and related defense genes to respond to CLas infection. These findings are valuable for developing novel strategies to combat citrus HLB.
Citrus huanglongbing (HLB) is a devastating disease for the citrus industry. The previous studies demonstrated that oxytetracycline and penicillin are effective antibiotics against
Liberibacter ...asiaticus (
Las). However, since
Las is uncultured, the mechanisms of action of antibiotics against
Las are still unclear. It was recently reported that the endophytic microbial communities are associated with the progression of citrus HLB after oxytetracycline and penicillin treatment. Therefore, we hypothesize that penicillin has greater antibacterial activity against
Las than oxytetracycline, which may be associated with the alteration of the structure and function of endophytic microbial communities in HLB-affected citrus in response to these antibiotics. To test this hypothesis, the microbiome of HLB-affected citrus leaves treated with these two antibiotics was analyzed using a metagenomic method. Our results indicate that the microbial structure and function in HLB-affected citrus were altered by these two antibiotics. The relative abundance of beneficial bacterial species, including
and
was higher in penicillin-treated plants compared to those treated with oxytetracycline, and the relative abundance of the bacterial species (such as
and
sp PCC 6803) associated with
Las survival was lower for penicillin-treated plants compared to oxytetracycline-treated plants. These results indicate that penicillin has greater antibacterial activity against
Las. Based on the metagenomic analysis, this study elucidated the mechanism for the observed increase in antibacterial activity of penicillin against
Las. The data presented here are not only invaluable for developing eco-friendly and effective biocontrol strategies to combat citrus HLB, but also provide a method for revealing mechanism of antimicrobial against uncultured bacteria in host.
The development of more effective tumor therapy remains challenging and has received widespread attention. In the past decade, there has been growing interest in synergistic tumor therapy based on ...supramolecular coordination complexes. Herein, we describe two triangular metallacycles (1 and 2) constructed by the formation of pyridyl boron dipyrromethene (BODIPY)-platinum coordination. Metallacycle 2 had considerable tumor penetration, as evidenced by the phenylthiol-BODIPY ligand imparting red fluorescent emission at ∼660 nm, enabling bioimaging, and transport visualization within the tumor. Based on the therapeutic efficacy of the platinum(II) acceptor and high singlet oxygen (
O
) generation ability of BODIPY, 2 was successfully incorporated into nanoparticles and applied in chemo-photodynamic tumor therapy against malignant human glioma U87 cells, showing excellent synergistic therapeutic efficacy. A half-maximal inhibitory concentration of 0.35 μM was measured for 2 against U87 cancer cells in vitro. In vivo experiments indicated that 2 displayed precise tumor targeting ability and good biocompatibility, along with strong antitumor effects. This work provides a promising approach for treating solid tumors by synergistic chemo-photodynamic therapy of supramolecular coordination complexes.
A series of 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) with different connection sites and conjugation length and fluorene alternating conjugated polymers have been synthesized via ...palladium-catalyzed Suzuki coupling reaction. The polymers were fully characterized by 1H NMR spectroscopy and gel permeation chromatography (GPC), and their properties were measured by thermogravimetric analysis (TGA), UV–vis absorption spectroscopy, cyclic voltammetry (CV), photoluminescence (PL) spectroscopy, the Z-scan technique, and theoretical calculation using density-functional theory (DFT) method. The results indicate that the connection sites and conjugation length of BODIPY have great effect on the optical-electronic and nonlinear optical properties of the conjugated BODIPY- fluorene copolymers although they don't affect the polymerization process. The absorption and emission peaks of P1 exhibit red shifts compared to those of P2 and P3. The polymers show good nonlinear optical properties that are closely related to the connection sites of the BODIPY pendants. P1 exhibits relatively richer nonlinear optical (NLO) properties than P2 and P3. The third order nonlinear optical coefficient (χ(3)) of P1 is 3.57 × 10−11 esu, which is ~4 times larger than those of P2 and P3.
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•A series of BODIPY and fluorene alternating conjugated polymers•Different connection sites and conjugation length•Nonlinear optical properties investigated by Z-scan technique
Screening of LED light source of the adapter solar trap lamp for trapping the citrus psyllid Lin Xiongjie, Fujian Academy of Agricultural Sciences, Fuzhou (China), Research Institute of Fruits; Fan Guocheng, Fujian Academy of Agricultural Sciences, Fuzhou (China), Research Institute of Fruits; Hu Hanqing, Fujian Academy of Agricultural Sciences, Fuzhou (China), Research Institute of Fruits
Zhiwu baohu,
20/Aug., Letnik:
39, Številka:
4
Journal Article
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