Mesoporous silica nanoparticles enhance the cytotoxicity of curcumin

Curcumin encapsulated in mesoporous silica nanoparticles showed improved solubility, in vitro release profile and significantly enhanced cell cytotoxicity compared to the pure drug

Combination of microporous hollow carbon spheres and nafion for the individual metal-free stripping detectionof Pb2+ and Cd2+

Here, the combination of Nafion with microporous hollow carbon spheres (MHCS) is first proposed to fabricate a disposable metal-free electrode for heavy metal stripping sensing. The MHCS-Nafion composite film electrode is prepared by drop-casting a mixture of MHCS and Nafion onto the lab-made screen-printed carbon electrode (SPCE*). Results demonstrate that the interfusion of MHCS into Nafion offers enhanced performance for the electro-enrichment and stripping of lead and cadmium over the only Nafion film: 1) abundant MHCS immobilized on the electrode surface serve as effective nucleation sites for metal ion reduction; 2) the mixing of MHCS into Nafion enlarges the active surface of negative-charged Nafion for the electrostatic adsorption of metal cations. The proposed MHCS-Nafion/SPCE* provides linear responses for Pb2+ and Cd2+ in the range of 2 - 200 mu g/L, with a detection limit of 1.37 and 1.63 mu g/L, respectively. Practical applications of the sensor in water sample detection with good accuracy have also been confirmed

Roots play a key role in drought-tolerance of poplars as suggested by reciprocal grafting between male and female clones

Drought stress influences the growth of plants and thus grafting has been widely used to improve tolerance to abiotic stresses. Poplars possess sex-specific responses to drought stress, but how male or female rootstock affect the grafted plant is little known. To explore the mechanisms underlying changes in drought tolerance caused by grafting, we investigated the changes in growth, leaf traits, gas exchange and antioxidant enzyme activities of reciprocally grafted seedlings between Populus euramericana cv. "Nanlin895" (NL-895) (female) and Populus deltiodes cv."3412" (NL-3412) (male) under water deficit stress with 30% field capacity for 30 d. Results showed that drought stress affected adversely growth, morphological, and physiological characteristics in all seedlings studied. Grafted seedlings with male roots can effectively alleviated the inhibition of growth induced by drought stress, as shown by higher WUE, activities of SOD, POD and CAT, and lower levels of lipid peroxidation. Male seedlings with female roots were found to be less tolerance to drought than non-grafted male clones and female scions with male roots, but more tolerance than non-grafted female clones. This results suggested that drought tolerance of grafted seedlings is primarily caused by the rootstock, although the scion also affects the grafted plant. Thus, paying attention on the root genotype can provide an important means of improving the drought tolerance of poplars.Peer reviewe

Functionalized large pore mesoporous silica nanoparticles for gene delivery featuring controlled release and co-delivery

Novel mesoporous silica nanoparticles (LPMSNs) functionalised with degradable poly(2-dimethylaminoethyl acrylate) (PDMAEA) have been developed (PDMAEA–LPMSNs) as nano-carriers for gene delivery. The unique design of PDMAEA–LPMSNs has endowed this system with multiple functions derived from both the organic and inorganic moieties. The cationic polymer unit binds to genetic molecules and undergoes a self-catalyzed hydrolysis in water to form a non-toxic anionic polymer poly(acrylic acid), allowing controlled release of siRNA in the cells. The nanopores of the LPMSNs provide a reservoir for storage and release of chloroquine to facilitate endosomal escape. The PDMAEA–LPMSN composites were characterized by elemental analysis (EA), X-ray photoelectron spectroscopy (XPS), solid-state 13C magic-angle spinning nuclear magnetic resonance (MAS-NMR), thermogravimetric analysis (TGA), and nitrogen sorption techniques. Their siRNA delivery performance was tested in a KHOS cell line, showing promising potential for co-delivery of genes and drugs

Shaping nanoparticles with hydrophilic compositions and hydrophobic properties as nanocarriers for antibiotic delivery

Inspired by the lotus effect in nature, surface roughness engineering has led to novel materials and applications in many fields. Despite the rapid progress in superhydrophobic and superoleophobic materials, this concept of Mother Nature’s choice is yet to be applied in the design of advanced nanocarriers for drug delivery. Pioneering work has emerged in the development of nanoparticles with rough surfaces for gene delivery; however, the preparation of nanoparticles with hydrophilic compositions but with enhanced hydrophobic property at the nanoscale level employing surface topology engineering remains a challenge. Herein we report for the first time the unique properties of mesoporous hollow silica (MHS) nanospheres with controlled surface roughness. Compared to MHS with a smooth surface, rough mesoporous hollow silica (RMHS) nanoparticles with the same hydrophilic composition show unusual hydrophobicity, leading to higher adsorption of a range of hydrophobic molecules and controlled release of hydrophilic molecules. RMHS loaded with vancomycin exhibits an enhanced antibacterial effect. Our strategy provides a new pathway in the design of novel nanocarriers for diverse bioapplications

Writing for Local Government Schools: Authors and Themes in Song-dynasty School Inscriptions

A hallmark of the Song dynasty\u27s achievements was the creation of a national network of state-sponsored local schools. This engendered an exponential growth of commemorative inscriptions dedicated to local government schools. Many authors used these inscriptions as an avenue to expound and disseminate their visions of schools and education. Using the methods of network analysis and document clustering, this article analyzes all the inscriptions extant from Song times for local government schools. It reveals a structural schism in the diffusion of ideas between the Upper Yangzi and other regions of the Song. It also demonstrates the growing intellectual influence of Neo-Confucian ideologues that gradually overtook that of renowned prose-writers. Methodologically, this article provides an example of how diverse digital methods enable us to handle a large body of texts from multiple perspectives and invite us to explore connections we might not have otherwise thought of. Free access link: https://www.cambridge.org/core/journals/journal-of-chinese-history/article/writing-for-local-government-schools-authors-and-themes-in-songdynasty-school-inscriptions/8917993FA5EC53FC837961E6B929856F/share/eb301b0b72c9781fb464765a830a50b029453e6

Pristine mesoporous carbon hollow spheres as safe adjuvants induce excellent Th2-biased immune response

The development of a safe and effective adjuvant that amplifies the immune response to an antigen is important for vaccine delivery. In this study, we developed pristine mesoporous carbon hollow spheres as high-capacity vaccine protein nanocarriers and safe adjuvants for boosting the immune response. Mono-dispersed invaginated mesostructured hollow carbon spheres (IMHCSs) have an average particle size of ∼200 nm, large pore size of 15 nm, and high pore volume of 2.85 cm·g. IMHCSs exhibited a very high loading capacity (1,040 μg·mg) towards ovalbumin (OVA, a model antigen), controlled OVA release behavior, excellent safety profile to normal cells, and high antigen delivery efficacy towards macrophages. In vivo immunization studies in mice demonstrated that OVA-loaded IMHCSs induced a 3-fold higher IgG response compared to a traditional adjuvant QuilA used in veterinary vaccine research. OVA delivered by IMHCSs induced a higher IgG1 concentration than IgG2a, indicating a T-helper 2 (Th2)-polarized response. Interferon-γ and interleukin-4 concentration analysis revealed both T-helper 1 (Th1) and Th2 immune responses induced by OVA-loaded IMHCSs. IMHCSs are safer adjuvants than QuilA. Our study revealed that pure IMHCSs without further functionalization can be used as a safe adjuvant for promoting Th2-biased immune responses for vaccine delivery

High-throughput monitoring of wild bee diversity and abundance via mitogenomics

1. Bee populations and other pollinators face multiple, synergistically acting threats, which have led to population declines, loss of local species richness and pollination services, and extinctions. However, our understanding of the degree, distribution and causes of declines is patchy, in part due to inadequate monitoring systems, with the challenge of taxonomic identification posing a major logistical barrier. Pollinator conservation would benefit from a high-throughput identification pipeline. 2. We show that the metagenomic mining and resequencing of mitochondrial genomes (mitogenomics) can be applied successfully to bulk samples of wild bees. We assembled the mitogenomes of 48 UK bee species and then shotgun-sequenced total DNA extracted from 204 whole bees that had been collected in 10 pan-trap samples from farms in England and been identified morphologically to 33 species. Each sample data set was mapped against the 48 reference mitogenomes. 3. The morphological and mitogenomic data sets were highly congruent. Out of 63 total species detections in the morphological data set, the mitogenomic data set made 59 correct detections (93�7% detection rate) and detected six more species (putative false positives). Direct inspection and an analysis with species-specific primers suggested that these putative false positives were most likely due to incorrect morphological IDs. Read frequency significantly predicted species biomass frequency (R2 = 24�9%). Species lists, biomass frequencies, extrapolated species richness and community structure were recovered with less error than in a metabarcoding pipeline. 4. Mitogenomics automates the onerous task of taxonomic identification, even for cryptic species, allowing the tracking of changes in species richness and istributions. A mitogenomic pipeline should thus be able to contain costs, maintain consistently high-quality data over long time series, incorporate retrospective taxonomic revisions and provide an auditable evidence trail. Mitogenomic data sets also provide estimates of species counts within samples and thus have potential for tracking population trajectories

Regulation of HIF1α under Hypoxia by APE1/Ref-1 Impacts CA9 Expression: Dual Targeting in Patient-Derived 3D Pancreatic Cancer Models

Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer-related mortality in the United States. Aggressive treatment regimens have not changed the disease course, and the median survival has just recently reached a year. Several mechanisms are proposed to play a role in PDAC therapeutic resistance, including hypoxia, which creates a more aggressive phenotype with increased metastatic potential and impaired therapeutic efficacy. AP Endonuclease-1/Redox Effector Factor 1 (APE1/Ref-1) is a multifunctional protein possessing a DNA repair function in base excision repair and the ability to reduce oxidized transcription factors, enabling them to bind to their DNA target sequences. APE1/Ref-1 regulates several transcription factors involved in survival mechanisms, tumor growth, and hypoxia signaling. Here, we explore the mechanisms underlying PDAC cell responses to hypoxia and modulation of APE1/Ref-1 redox signaling activity, which regulates the transcriptional activation of hypoxia-inducible factor 1 alpha (HIF1α). Carbonic anhydrase IX (CA9) is regulated by HIF1α and functions as a part of the cellular response to hypoxia to regulate intracellular pH, thereby promoting cell survival. We hypothesized that modulating APE1/Ref-1 function will block activation of downstream transcription factors, STAT3 and HIF1α, interfering with the hypoxia-induced gene expression. We demonstrate APE1/Ref-1 inhibition in patient-derived and established PDAC cells results in decreased HIF1α–mediated induction of CA9. Furthermore, an ex vivo three-dimensional tumor coculture model demonstrates dramatic enhancement of APE1/Ref-1–induced cell killing upon dual targeting of APE1/Ref-1 and CA9. Both APE1/Ref-1 and CA9 are under clinical development; therefore, these studies have the potential to direct novel PDAC therapeutic treatment