Single-cell analysis of the miRNA activities in tuberculous meningitis (TBM) model mice injected with the BCG vaccine.

BACKGROUND: Our previous study revealed the transcriptome atlas of specific cell types in tuberculous meningitis (TBM) model mice injected with the BCG vaccine via scRNA sequencing. However, the activities of miRNAs in TBM at single-cell resolution remain to be explored. METHOD: Cell type-specific miRNA activities were investigated by using motif enrichment analyses (miReact) on the transcriptome data of 15 cell types. The target mRNAs of miRNAs were predicted and subjected to enrichment analysis. Furthermore, miRNAs and their target mRNAs with opposite expression trends were chosen to construct functional networks. Besides, qRT-PCR and RNA scope were performed to verify the expression level of representative miRNA. RESULTS: The tSNE dimensionality reduction presented 15 cell types in TBM model mice, in which microglia and endothelial cells accounted for the majority. Target mRNAs of each cell type were predicted for verification or network construction. The immune and inflammation-related miRNA-mRNA networks of macrophages and microglia, oxidative phosphorylation-related miRNA-mRNA networks of neurons, ion and protein transport-related networks of epididymal cells, and angiogenesis-related miRNA-mRNA networks of VSMCs were constructed. The miRNA activity analysis revealed that miR-21a-3p activity was increased in microglia, macrophages, neurons and epididymal cells. The result of qRT-PCR and RNA scope indicate that miR-21a-3p was significantly higher-expressed in TBM brain tissue compared with normal brain tissue. CONCLUSION: In our study, an in-depth exploration of the mRNA expression and miRNA activity of macrophages, microglia, epididymal cells, neurons and vascular smooth muscle cells during TBM progression was conducted using scRNA-Seq, which provided novel insights into the immune cell engagement in TBM patients.

Elucidation of Substantial Differences in Ring-Opening Polymerization Outcomes from Subtle Variation of Glucose Carbonate-Based Monomer Substitution Patterns and Substituent Types.

The substituents present upon five-membered bicyclic glucose carbonate monomers were found to greatly affect the reactivities and regioselectivities during ring-opening polymerization (ROP), which contrast in significant and interesting ways from previous studies on similar systems, while also leading to predictable effects on the thermal properties of the resulting polycarbonates. Polymerization behaviors were probed for a series of five five-membered bicyclic 2,3-glucose-carbonate monomers having 4,6-ether, -carbonate, or -sulfonyl urethane protecting groups, under catalysis with three different organobase catalysts. Irrespective of the organobase catalyst employed, regioregular polycarbonates were obtained via ROP of monomers with ether substituents, while the backbone connectivities of polymers derived from monomers with carbonate protecting groups suffered transcarbonylation reactions, resulting in irregular backbone connectivities and broad molar mass distributions. The sulfonyl urethane-protected monomers were unable to undergo organobase-catalyzed ROP, possibly due to the acidity of the proton in urethane functionality. The thermal behaviors of polycarbonates with ether and carbonate pendant groups were investigated in terms of thermal stability and glass transition temperature (Tg). A two-stage thermal decomposition was observed when tert-butyloxycarbonyl (BOC) groups were employed as protecting side chains, while all other polycarbonates presented high thermal stabilities with a single-stage thermal degradation. Tg was greatly affected by side-chain bulkiness, with values ranging from 39 to 139 °C. These fundamental findings of glucose-based polycarbonates may facilitate the development of next-generation sustainable highly functional materials.

Morphologic design of nanostructures for enhanced antimicrobial activity.

Despite significant progress in synthetic polymer chemistry and in control over tuning the structures and morphologies of nanoparticles, studies on morphologic design of nanomaterials for the purpose of optimizing antimicrobial activity have yielded mixed results. When designing antimicrobial materials, it is important to consider two distinctly different modes and mechanisms of activity-those that involve direct interactions with bacterial cells, and those that promote the entry of nanomaterials into infected host cells to gain access to intracellular pathogens. Antibacterial activity of nanoparticles may involve direct interactions with organisms and/or release of antibacterial cargo, and these activities depend on attractive interactions and contact areas between particles and bacterial or host cell surfaces, local curvature and dynamics of the particles, all of which are functions of nanoparticle shape. Bacteria may exist as spheres, rods, helices, or even in uncommon shapes (e.g., box- and star-shaped) and, furthermore, may transform into other morphologies along their lifespan. For bacteria that invade host cells, multivalent interactions are involved and are dependent upon bacterial size and shape. Therefore, mimicking bacterial shapes has been hypothesized to impact intracellular delivery of antimicrobial nanostructures. Indeed, designing complementarities between the shapes of microorganisms with nanoparticle platforms that are designed for antimicrobial delivery offers interesting new perspectives toward future nanomedicines. Some studies have reported improved antimicrobial activities with spherical shapes compared to non-spherical constructs, whereas other studies have reported higher activity for non-spherical structures (e.g., rod, discoid, cylinder, etc.). The shapes of nano- and microparticles have also been shown to impact their rates and extents of uptake by mammalian cells (macrophages, epithelial cells, and others). However, in most of these studies, nanoparticle morphology was not intentionally designed to mimic specific bacterial shape. Herein, the morphologic designs of nanoparticles that possess antimicrobial activities per se and those designed to deliver antimicrobial agent cargoes are reviewed. Furthermore, hypotheses beyond shape dependence and additional factors that help to explain apparent discrepancies among studies are highlighted.

Transcriptomic Identification and Expression Profile Analysis of Odorant-Degrading Enzymes from the Asian Corn Borer Moth, Ostrinia furnacalis.

The Asian corn borer moth Ostrinia furnacalis is an important lepidopteran pest of maize in Asia. Odorant-degrading enzymes (ODEs), including carboxylesterases (CCEs), glutathione S-transferases (GSTs), cytochrome P450s (CYPs), UDP-glycosyltransferases (UGTs), and aldehyde oxidases (AOXs), are responsible for rapid inactivation of odorant signals in the insect antennae. In this study, we performed a transcriptome assembly for the antennae of O. furnacalis to identify putative ODE genes. Transcriptome sequencing revealed 35,056 unigenes, and 21,012 (59.94%) of these were annotated by searching against the reference sequences in the NCBI non-redundant (NR) protein database. For functional classification, these unigenes were subjected to Gene Ontology (GO), Eukaryotic Orthologous Groups (KOG), and Kyoto Encyclopedia of Genes and Genomes (KEGG) annotations. We identified 79 genes encoding putative ODEs: 19 CCEs, 17 GSTs, 24 CYPs, 13 UGTs, and 6 AOXs. BLASTX best hit results indicated that these genes shared quite high amino acid identities with their respective orthologs from other lepidopteran species. Reverse transcription-quantitative PCR showed that OfurCCE2, OfurCCE5, and OfurCCE18 were enriched in male antennae, while OfurCCE7 and OfurCCE10 were enriched in female antennae. OfurCCE14 and OfurCCE15 were expressed at near-equal amounts in the antennae of both sexes. Our findings establish a solid foundation for future studies aimed at understanding the olfactory functions of these genes in O. furnacalis.

Complexities of Regioselective Ring-Opening vs Transcarbonylation-Driven Structural Metamorphosis during Organocatalytic Polymerizations of Five-Membered Cyclic Carbonate Glucose Monomers.

Rigorous investigations of the organobase-catalyzed ring-opening polymerizations (ROPs) of a series of five-membered cyclic carbonate monomers derived from glucose revealed that competing transcarbonylation reactions scrambled the regiochemistries of the polycarbonate backbones. Regioirregular poly(2,3-α-d-glucose carbonate) backbone connectivities were afforded by 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD)-catalyzed ROPs of three monomers having different cyclic acetal protecting groups through the 4- and 6-positions. Small molecule studies conducted upon isolated unimers and dimers indicated a preference for Cx-O2 vs Cx-O3 bond cleavage from tetrahedral intermediates along the pathways of addition-elimination mechanisms when the reactions were performed at room temperature. Furthermore, treatment of isolated 3-unimer or 2-unimer, having the carbonate linkage in the 3- or 2-position as obtained from either Cx-O2 or Cx-O3 bond cleavage, respectively, gave the same 74:26 (3-unimer:2-unimer) ratio, confirming the occurrence of transcarbonylation reactions with a preference for 3-unimer vs. 2-unimer formation in the presence of organobase catalyst at room temperature. In contrast, unimer preparation at -78 °C favored Cx-O3 bond cleavage to afford a majority of 2-unimer, presumably due to a lack of transcarbonylation side reactions. Computational studies supported the experimental findings, enhancing fundamental understanding of the regiochemistry resulting from the ring-opening and subsequent transcarbonylation reactions during ROP of glucose carbonates. These findings are expected to guide the development of advanced carbohydrate-derived polymer materials by an initial monomer design via side chain acetal protecting groups, with the ability to evolve the properties further through later-stage structural metamorphosis.

Morphologic Design of Silver-Bearing Sugar-Based Polymer Nanoparticles for Uroepithelial Cell Binding and Antimicrobial Delivery.

Platelet-like and cylindrical nanostructures from sugar-based polymers are designed to mimic the aspect ratio of bacteria and achieve uroepithelial cell binding and internalization, thereby improving their potential for local treatment of recurrent urinary tract infections. Polymer nanostructures, derived from amphiphilic block polymers composed of zwitterionic poly(d-glucose carbonate) and semicrystalline poly(l-lactide) segments, were constructed with morphologies that could be tuned to enhance uroepithelial cell binding. These nanoparticles exhibited negligible cytotoxicity, immunotoxicity, and cytokine adsorption, while also offering substantial silver cation loading capacity, extended release, and in vitro antimicrobial activity (as effective as free silver cations) against uropathogenic Escherichia coli. In comparison to spherical analogues, cylindrical and platelet-like nanostructures engaged in significantly higher association with uroepithelial cells, as measured by flow cytometry; despite their larger size, platelet-like nanostructures maintained the capacity for cell internalization. This work establishes initial evidence of degradable platelet-shaped nanostructures as versatile therapeutic carriers for treatment of epithelial infections.

LncRNA NUTM2A-AS1 positively modulates TET1 and HIF-1A to enhance gastric cancer tumorigenesis and drug resistance by sponging miR-376a.

Long noncoding RNA NUTM2A-AS1 has been shown to be dysregulated in non-small cell lung carcinoma. To date, it is unclear whether NUTM2A-AS1 plays a role in gastric cancer progression. The purpose of this study is to elucidate the molecular mechanism of the role of NUTM2A-AS1 in gastric cancer. mRNA and protein levels were measured by RT-qPCR and western blot methods. Invasion ability was examined by transwell assay. Cell viability was determined by MTT assay. Dual-luciferase assay, RNA pull down, and RNA immunoprecipitation were used to confirm direct binding of between miR-376a and NUTM2A-AS1 or TET1. Xenografting tumor assay and TCGA analysis showed the contributory role of NUTM2A-AS1 in vivo and human clinical setting. Our results suggested that NUTM2A-AS1 promoted cell viability, invasion, and drug resistance of gastric cancer cells, which was largely rescued by miR-376a. More interestingly, TET1 and HIF-1A were negatively regulated by miR-376a. TET1 could interact with HIF-1A to modulate PD-L1. Finally, we revealed that PD-L1 was key to NUTM2A-AS1- and miR-376a-mediated tumorigenesis and drug resistance. In summary, our conclusions facilitate us understand the underlying mechanism and develop novel treatment strategy for gastric cancer.

Invoking Side-Chain Functionality for the Mediation of Regioselectivity during Ring-Opening Polymerization of Glucose Carbonates.

The extent of participation of side-chain functionalities during the 1,5,7-triazabicyclo[5.4.0]dec-5-ene (TBD) organobase-catalyzed ring-opening polymerizations (ROP) of six-membered cyclic d-glucose-based carbonates was found to result in significantly different regiochemical outcomes. High regioselectivity was observed for naturally derived poly(4,6-d-glucose carbonate)s (PGCs) containing carbonate side chain substituents in the 2- and 3-positions, whereas regioirregularity was found for analogous PGCs with ether side-chain substituents. The backbone connectivities and structural details of these PGCs were examined through a combination of comprehensive 1D and 2D NMR studies on unimers and dimers, verifying the ring-opening preferences and indicating the contribution of side-chain functionalities in regioselective ROP processes. A molecular understanding of the curious role of side-chain functionalities was demonstrated via density functional theory calculations, revealing stabilization effects of intermolecular hydrogen bonding between the side-chain functionalities and TBD in the transition states. Overall, this work provides fundamental insights into the organocatalytic ROP of these specific six-membered asymmetric cyclic glucose carbonates. More importantly, these findings serve as a foundation for future design strategies that incorporate adjacent functionalities within monomers to act as directing groups and impart molecular interactions that define regiochemical ring-opening.

A Tale of Drug-Carrier Optimization: Controlling Stimuli Sensitivity via Nanoparticle Hydrophobicity through Drug Loading.

Interactions between drug molecules, nanocarrier components, and surrounding media influence the properties and therapeutic efficacies of nanomedicines. In this study, we investigate the role that reversible covalent loading of a hydrophobic drug exerts on intra-nanoparticle physical properties and explore the utility of this payload control strategy for tuning the access of active agents and, thereby, the stimuli sensitivity of smart nanomaterials. Glutathione sensitivity was controlled via altering the degree of hydrophobic payload loading of disulfide-linked camptothecin-conjugated sugar-based nanomaterials. Increases in degrees of camptothecin conjugation (fCPT) decreased aqueous accessibility and reduced glutathione-triggered release. Although the lowest fCPT gave the fastest camptothecin release, it resulted in the lowest camptothecin concentration. Remarkably, the highest fCPT resulted in a 5.5-fold improved selectivity against cancer vs noncancerous cells. This work represents an advancement in drug carrier design by demonstrating the importance of controlling the amount of drug loading on the overall payload and its availability.

Applications of Inorganic Nanomaterials in Photothermal Therapy Based on Combinational Cancer Treatment.

BACKGROUND: Cancer is one of the major causes of death and is difficult to cure using existing clinical therapies. Clinical cancer treatments [such as surgery, chemotherapy (CHT), radiotherapy (RT) and immunotherapy (IT)] are widely used but they have limited therapeutic effects and unavoidable side effects. Recently, the development of novel nanomaterials offers a platform for combinational therapy (meaning a combination of two or more therapeutic agents) which is a promising approach for cancer therapy. Recent studies have demonstrated several types of nanomaterials suitable for photothermal therapy (PTT) based on a near-infrared (NIR) light-responsive system. PTT possesses favorable properties such as being low in cost, and having high temporospatial control with minimal invasiveness. However, short NIR light penetration depth limits its functions. METHODS: In this review, due to their promise, we focus on inorganic nanomaterials [such as hollow mesoporous silica nanoparticles (HMSNs), tungsten sulfide quantum dots (WS2QDs), and gold nanorods (AuNRs)] combining PTT with CHT, RT or IT in one treatment, aiming to provide a comprehensive understanding of PTT-based combinational cancer therapy. RESULTS: This review found much evidence for the use of inorganic nanoparticles for PTT-based combinational cancer therapy. CONCLUSION: Under synergistic effects, inorganic nanomaterial-based combinational treatments exhibit enhanced therapeutic effects compared to PTT, CHT, RT, IT or PDT alone and should be further investigated in the cancer field.

In Situ Production of Ag/Polymer Asymmetric Nanoparticles via a Powerful Light-Driven Technique.

As a rapid, controllable, and easily transferrable approach to the preparation of antimicrobial nanoparticle systems, a one-step, light-driven procedure was developed to produce asymmetric hybrid inorganic-organic nanoparticles (NPs) directly from a homogeneous Ag/polymer mixture. An amphiphilic triblock polymer was designed and synthesized to build biocompatible NPs, consisting of poly(ethylene oxide) (PEO), carboxylic acid-functionalized polyphosphoester (PPE), and poly(l-lactide) (PLLA). Unexpectedly, snowman-like asymmetric nanostructures were subsequently obtained by simply loading silver cations into the polymeric micelles together with purification via centrifugation. With an understanding of the chemistry of the asymmetric NP formation, a controllable preparation strategy was developed by applying UV irradiation. A morphology transition was observed by transmission electron microscopy over the UV irradiation time, from small silver NPs distributed inside the micelles into snowman-like asymmetric NPs, which hold promise for potential antimicrobial applications with their unique two-stage silver release profiles.

Isotope and Hydrogen-Bond Effects on the Self-Assembly of Macroions in Dilute Solution.

We report on the disparity in the assembly behavior of four types of nano-sized macroions induced by isotopic substitution of protium (H) to deuterium (D) in solvents. Macroions with modest charge density can self-assemble into single-layer, hollow, spherical "blackberry"-type structures, with larger assembly sizes representing stronger attractions among the macroions. Kinetically, all assembly processes become slower in D2 O than in H2 O. Thermodynamically, the polyoxometalate {SrPd12 }, the uranium cage {U60 } with alkali metal counterions, and the metal-organic cationic cage {Pd12 L24 } demonstrate similar assembly sizes in both H2 O and D2 O, whereas the metal oxide cluster {Mo72 Fe30 } as a weak acid shows an unusually large assembly size in H2 O-suggesting a stronger contribution from the hydrogen bonding in the last case.

Tuning the Intercage Distance in Charge-Regulated Blackberry-Type Assemblies through Host-Guest Chemistry.

Charged or neutral adamantane guests can be encapsulated into the cavity of cationic metal-organic M6 L4 (bpy-cage, M=PdII (2,2'-bipyridine), L=2,4,6-tri(4-pyridyl)-1,3,5-triazine) cages through hydrophobic interaction. These encapsulations can provide an approach to control the net charge on the resulting cage-guest complexes and regulate their charge-dominated assembly into hollow spherical blackberry-type assemblies in dilute solutions: encapsulation of neutral guests will hardly influence their self-assembly process, including the blackberry structure size, which is directly related to the intercage distance in the assembly; whereas encapsulating negatively (positively) charged guests resulted in a shorter (longer) intercage distance with larger (smaller) assemblies formed. Therefore, the host-guest chemistry approach can be used to tune the intercage distance accurately.

Conformational change due to intramolecular hydrophobic interaction leads to large blue-shifted emission from single molecular cage solutions.

We demonstrate a unique negative solvatochromic emission (NSE) process from a conformational change of a coordination cage in response to solvent composition. The cationic cage contains two tetra-(4-pyridylphenyl)ethylene (TPPE) luminogens on two opposite faces, linked by Pt(PEt3)2 and isophthalate. When the solvent changes from acetone/acetonitrile/methanol to water, the emission of single cages gradually shifts to short wavelength (NSE) with a drastic value of ∼60 nm. Small angle X-ray scattering (SAXS) measurements indicate a molecular conformational change during the process and intramolecular π-π stacking and hydrophobic interaction between the TPPE planes could be the driving forces. As a comparison, a cage with a longer inter-fluorophore distance does not have such strong intramolecular interactions and only shows regular positive solvatochromic emission (PSE) under the same conditions.