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Iron plays a crucial role in plant chlorophyll synthesis, respiration, and plant growth. However, excessive iron content can contribute to ginseng poisoning. We previously discovered that the application of silicon (Si) and potassium (K) can mitigate the iron toxicity on ginseng. To elucidate the molecular mechanism of how Si and K alleviate iron toxicity stress in ginseng. We investigated the physiological and transcriptional effects of exogenous Si and K on Panax ginseng. The results suggested that the leaves of ginseng with Si and K addition under iron stress increased antioxidant enzyme activity or secondary metabolite content, such as phenylalanine amino-lyase, polyphenol oxidase, ascorbate peroxidase, total phenols and lignin, by 6.21%–25.94%, 30.12%–309.19%, 32.26%–38.82%, 7.81%–23.66%, and 4.68%–48.42%, respectively. Moreover, Si and K increased the expression of differentially expressed genes (DEGs) associated with resistance to both biotic and abiotic stress, including WRKY (WRKY1 , WRKY5 , and WRKY65), bHLH (bHLH35 , bHLH66 , bHLH128 , and bHLH149), EREBP , ERF10 and ZIP. Additionally, the amount of DEGs of ginseng by Si and K addition was enriched in metabolic processes, single-organism process pathways, signal transduction, metabolism, synthesis and disease resistance. In conclusion, the utilization of Si and K can potentially reduce the accumulation of iron in ginseng, regulate the expression of iron tolerance genes, and enhance the antioxidant enzyme activity and secondary metabolite production in both leaves and roots, thus alleviating the iron toxicity stress in ginseng. [Display omitted] • The leaf was the important part of Si and K to alleviate the iron toxicity of ginseng. • Exogenous Si and K can improve the tolerance of ginseng to iron toxicity. • Si and K can increase the activity of ginseng antioxidant enzymes and remove O 2 ·–. • Si and K enhanced ginseng secondary metabolite genes, reducing iron toxicity. • Si and K up-regulated transcription factors and genes involved in iron homeostasis. [ABSTRACT FROM AUTHOR]

Ginseng, a crucial medicinal plant in China, faces challenges due to rusty roots (GRR). Our early work linked GRR to nitrate-reducing Fe (II) oxidation (NRFO). However, the interaction between the NRFO and soil microorganisms how impact the GRR occurrence remain elusive. To elucidate how iron and nitrogen influence microbial community structure, diversity and functional characteristics during the soil of GRR occurrence. Here, we showed that the GRR occurred might be related to the soil microbial abundance associated with NRFO increased, such as Shewanella , Geobacter and Acidovorax (P < 0.05). Interestingly, LeFSe analysis suggested that soil microorganism (Allorhizobium-Neorhizobium-Pararhizobium-Rhizobium) involved in nitrogen cycling were enriched in GRR soils (P < 0.05, LDA > 2.5). Moreover, structural equation model analysis showed that increasing pH-mediated Fe (II) content and upregulation of expression genes (i.e., K15637) controlling microbial cell death may be significantly correlated with the decrease in bacterial diversity (P < 0.05), thus increasing the occurrence index of GRR (P < 0.01). Additionally, metagenomics function annotations indicated that the genes enriched in cell wall/membrane/envelope biogenesis and the carbohydrate uptakes were decreased, which may also be one of the factors contributing to the aggravation of GRR. Furthermore, we found that the genus of Bryobacter , Sphingobium and Luteibacter enriched in healthy samples soil may inhibit GRR. In conclusion, iron-nitrogen coupling alters microbial communities, diversity and gene expression, impacting GRR occurrence. These findings provide a new perspective for understanding the formation mechanism of GRR based on the influence of iron and nitrogen cycle on microbial gene expression. [Display omitted] • Increasing Fe (II) has reduced microbial diversity and upregulated K15637 gene. • The K15637 upregulation may promote the formation of ginseng rust root (GRR). • The cell wall/membrane/envelope biogenesis and carbohydrate uptake exacerbated GRR. • The Shewanella , Geobacter and Acidovorax may be associated with formation of GRR. • The Sphingobium and Luteibacte related to iron-nitrogen coupling may suppress GRR. [ABSTRACT FROM AUTHOR]

Weak tissue adhesion remains a major challenge in clinical translation of microneedle patches. Mimicking the structural features of honeybee stingers, stiff polymeric microneedles with unidirectionally backward-facing barbs were fabricated and embedded into various elastomer films to produce self-interlocking microneedle patches. The spirality of the barbing pattern was adjusted to increase interlocking efficiency. In addition, the micro-bleeding caused by microneedle puncturing adhered the porous surface of the patch substrate to the target tissue via coagulation. In the demonstrative application of myocardial infarction treatment, the bioinspired microneedle patches firmly fixed on challenging beating hearts, significantly reduced cardiac wall stress and strain in the infarct, and maintained left ventricular function and morphology. In addition, the microneedle patch was minimally invasively implanted onto beating porcine heart in 10 minutes, free of sutures and adhesives. Therefore, the honeybee stinger-inspired microneedles could provide an adaptive and convenient means to implant patches for various medical applications. Adhesion between tissue and microneedle patches with smooth microneedles is usually weak. We introduce a novel barbing method of fabricating unidirectionally backward facing barbs with controllable spirality on the microneedles on microneedle patches. The microneedle patches self-interlock on mechanically dynamic beating hearts, similar to honeybee stingers. The micro-bleeding and coagulation on the porous surface provide additional adhesion force. The microneedle patches attenuate left ventricular remodeling via mechanical support and are compatible with minimally invasive implantation. [Display omitted] [ABSTRACT FROM AUTHOR]

Background and Aims: Skin autofluorescence (SAF) can non-invasively assess the accumulation of tissue AGEs. We investigated the association between SAF and kidney dysfunction in participants with T2D.Methods: Of 4030 participants consecutively measured SAF at baseline, 3725 participants free of end-stage kidney disease (ESKD) were included in the analyses. The association of SAF with incident ESKD or ≥30% reduction in estimated glomerular filtration rate (eGFR) was examined with Cox regression, linear mixed-effects model for the association with annual eGFR decline, and mediation analyses for the mediating roles of renal markers.Results: During a median (IQR) 1.8 (1.1-3.1) years of follow-up, 411 participants developed the outcome. SAF was associated with progression of kidney disease (hazard ratio 1.15 per SD, 95% confidence interval [CI] [1.04, 1.28]) and annual decline in eGFR (β -0.39 per SD, 95% CI [-0.71, -0.07]) after adjustment for risk factors, including baseline eGFR and urinary albumin-creatinine ratio (UACR). Decreased eGFR (12.9%) and increased UACR (25.8%) accounted for 38.7% of the effect of SAF on renal outcome.Conclusions: SAF is independently associated with progression of kidney disease. More than half of its effect is independent of renal markers. SAF is of potential to be a prognostic marker for kidney dysfunction. [ABSTRACT FROM AUTHOR]

Phenoloxidase (PO) catalyzed melanization and other insect immune responses are mediated by serine proteases (SPs) and their noncatalytic homologs (SPHs). Many of these SP-like proteins have a regulatory clip domain and are called CLIPs. In most insects studied so far, PO precursors are activated by a PAP (i.e., PPO activating protease) and its cofactor of clip-domain SPHs. Although melanotic encapsulation is a well-known refractory mechanism of mosquitoes against malaria parasites, it is unclear if a cofactor is required for PPO activation. In Anopheles gambiae , CLIPA4 is 1:1 orthologous to Manduca sexta SPH2; CLIPs A5−7, A12–14, A26, A31, A32, E6, and E7 are 11:4 orthologous to M. sexta SPH1a, 1b, 4, and 101, SPH2 partners in the cofactors. Here we produced proCLIPs A4, A6, A7Δ, A12, and activated them with CLIPB9 or M. sexta PAP3. A. gambiae PPO2 and PPO7 were expressed in Escherichia coli for use as PAP substrates. CLIPB9 was mutated to CLIPB9 Xa by including a Factor X a cleavage site. CLIPA7Δ was a deletion mutant with a low complexity region removed. After PAP3 or CLIPB9 Xa processing, CLIPA4 formed a high M r complex with CLIPA6, A7Δ or A12, which assisted PPO2 and PPO7 activation. High levels of specific PO activity (55−85 U/μg for PO2 and 1131−1630 U/μg for PO7) were detected in vitro , indicating that cofactor-assisted PPO activation also occurs in this species. The cleavage sites and mechanisms for complex formation and cofactor function are like those reported in M. sexta and Drosophila melanogaster. In conclusion, these data suggest that the three (and perhaps more) SPHI-II pairs may form cofactors for CLIPB9-mediated activation of PPOs for melanotic encapsulation in A. gambiae. [Display omitted] • A. gambiae CLIPB9x a cleaved proCLIPA4, 6, 7Δ, and 12 to form its own cofactors. • M. sexta PAP3 more efficiently produced the cofactors for A. gambiae PPO activation. • CLIPs A6, A7Δ, or A12 pairs with CLIPA4 for PPO2/7 activation by CLIPB9 or PAP3. • Cleavages of pro-cSPHIs at site-1 and -2 and pro-cSPHII at site-1 are conserved. • Direct biochemical analysis based on orthology is useful for functional elucidation. [ABSTRACT FROM AUTHOR]

Holotrichia oblita is one of the nastiest pests in China. In present research, four full-length cDNA encoding of HoblOBP genes were cloned and sequenced from H. oblita. The mRNA of HoblOBPs were predominantly expressed in antenna. The recombinant HoblOBPs proteins were obtained for fluorescence binding assays. Four of HoblOBPs could mediate the response of H. oblita to organic fertilizers-derived attractants, including HoblOBP5 binding to skatole; HoblOBP8 binding to p-cresol, indole and skatole; HoblOBP9 binding to indole and 4-allylanisole; and HoblOBP24 binding to p-cresol, indole and 4-ethylphenol. Further, RNA interference demonstrated that transcripts of HoblOBP5 , 8 , 9 , and 24 decreased in a time-dependent manner after dsRNA-injection. Knockdown of HoblOBP5 , 8 , 9 , and 24 by injection of dsRNA successfully interfered with behavioral responses towards the target compounds in beetles. Our results showed that HoblOBP5, HoblOBP8, HoblOBP9 and HoblOBP24 are essential in mediating the approach behavior of H. oblita. • Six recombinant HoblOBPs from Holotrichia oblita was expressed and purified. • HoblOBP5 , 8 , 9 , and 24 showed high binding affinity to five compounds. • RNA interference demonstrated that HoblOBP5 , 8 , 9 , and 24 are essential in mediating the approach behavior of H. oblita. [ABSTRACT FROM AUTHOR]

• Mixed reality three-dimensional imaging is in a stable state. • The neurosurgeon's feedback of mixed reality equipment was satisfactory. • Mixed reality can improve the anatomical perception of neurosurgeons. • Mixed reality neuronavigation has great development prospect in neurosurgery. During neurological surgery, neurosurgeons have to transform the two-dimensional (2D) sectional images into three-dimensional (3D) structures at the cognitive level. The complexity of the intracranial structures increases the difficulty and risk of neurosurgery. Mixed reality (MR) applications reduce the obstacles in the transformation from 2D images to 3D visualization of anatomical structures of central nervous system. In this study, the holographic image was established by MR using computed tomography (CT), computed tomography angiography (CTA) and magnetic resonance imaging (MRI) data of patients. The surgeon's field of vision was superimposed with the 3D model of the patient's intracranial structure displayed on the mixed reality head-mounted display (MR-HMD). The neurosurgeons practiced and evaluated the feasibility of this technique in neurosurgical cases. We developed the segmentation image masks and texture mapping including brain tissue, intracranial vessels, nerves, tumors, and their relative positions by MR technologies. The results showed that the three-dimensional imaging is in a stable state in the operating room with no significant flutter and blur. And the neurosurgeon's feedback on the comfort of the equipment and the practicality of the technology was satisfactory. In conclusion, MR technology can holographically construct a 3D digital model of patient's lesions and improve the anatomical perception of neurosurgeons during craniotomy. The feasibility of the MR-HMD application in neurosurgery is confirmed. [ABSTRACT FROM AUTHOR]

Bacterial biofilm-associated infection has been one of the largest threats to global public health due to serious antibiotic resistance. It is urgently needed to develop new bactericides beyond antibiotics for biofilm eradication. Herein, we repurpose a hypoxia-activated anticancer drug tirapazamine (TPZ) to treat biofilm-associated infections based on the hypoxic biofilm microenvironment. A "hypoxia-enhanced" strategy is adopted to improve the therapeutic efficacy of TPZ by encapsulating TPZ into raspberry-like gold nanoparticle-hybrid liposomes (Lip@Au-TPZ). The gold nanoparticles on the hybrid liposomes can be used as nanozymes to catalyze glucose oxidation, which will consume oxygen to aggravate biofilm hypoxia. The aggravation of biofilm hypoxia is a critical step to metabolize TPZ into fatal oxidising radicals to induce DNA damage. The radical-induced damage of bacterial DNA by hypoxia-activated TPZ is fully investigated by multiple characterizations, including comet assay, nucleic acid gel electrophoresis, and bacterial gene transcriptome sequencing. Compared to liposome encapsulated TPZ (Lip-TPZ), Lip@Au-TPZ can lead to two orders of magnitude more reduction of bacterial cells due to the gold nanozyme-aggravated biofilm hypoxia. The biofilm eradication effect of Lip@Au-TPZ is further investigated in vivo by a mouse pneumonia model and a mouse wound healing model. The "hypoxia-enhanced" antibiofilm strategy by combining gold nanozymes and TPZ provides a new strategy for combating biofilm-associated infections. All data supporting the findings of the current study are available in the article and its Supplemental Information. Additional relevant data are available from the corresponding author upon reasonable request. [Display omitted] ● Gold nanozyme-hybrid liposomes are prepared with a "deposition-precipitation-reduction" method. ● Hypoxic prodrug could be activated by nanozyme-hybrid liposomes. ● Bacterial DNA damage is proved by comet assay. ● Lip@Au-TPZ prime an efficient hypoxia-enhanced biofilm eradication. ● Anti-biofilm ability driven by Lip@Au-TPZ may be related to the perturbation of respiration. [ABSTRACT FROM AUTHOR]

The equilibrium geometries, stabilities, chemical bonding, and aromaticity of the ground state of iridium low-nitride Ir 3 N 3 2+/0/2− clusters and their metal complexes Ir 3 N 3 M −/0 (M = Li, Na, K and Be, Mg, Ca) or Ir 3 N 3 M 2 (M = Li, Na, and K) are investigated using density functional theory (DFT) calculations. The bare Ir 3 N 3 2+/0/2− clusters favor perfectly planar D 3h structure. The neutral Ir 3 N 3 favors the 3 A 2 ″ triplet state, the Ir 3 N 3 2+ cation prefer to the 1 A 1 ′ singlet state, and the Ir 3 N 3 2− dianion is found also to be a 1 A 1 ′ singlet state. A detailed molecular orbitals (MOs) analysis reveals that the Ir 3 N 3 (D 3h , 3 A 2 ″) cluster possesses multiple (σ-, π-, and partial δ-) aromaticity and the Ir 3 N 3 2− (D 3h , 1 A 1 ′) dianion possesses double (σ- and π-) aromaticity. The Ir 3 N 3 2− (D 3h , 1 A 1 ′) motif structure was perfectly preserved in the pyramidal Ir 3 N 3 M −/0 and bipyramidal Ir 3 N 3 M 2 complexes, which also possess corresponding aromatic characters. [ABSTRACT FROM AUTHOR]

The equilibrium geometries, harmonic vibrational frequencies, stabilities, and chemical bonding of the low-lying states for all-metal Hg 3 Al 3 +/− , Hg 3 Al 3 Li, and Hg 3 Al 3 Be + clusters are investigated using 2nd order Møller–Plesset perturbation theory. The extensive search for the global minimum structures of Hg 3 Al 3 +/− at the MP2 level of theory with 6-311++G∗ basis set for Al and CEP-121 G basis set for Hg reveals that the ground states of the Hg 3 Al 3 + and Hg 3 Al 3 − clusters are all singlet state 1 A′ with C s symmetry. A detailed molecular orbital (MO) analysis reveals that the Hg 3 Al 3 + (C s , 1 A′) cation and Hg 3 Al 3 − (C s , 1 A′) anion possess double aromaticity (simultaneous presence of σ- and π-aromaticity). The hexagonal pyramidal-type Hg 3 Al 3 Li and Hg 3 Al 3 Be + complexes containing the Hg 3 Al 3 − ligand reveal that the Hg 3 Al 3 − structural units are preserved in the Hg 3 Al 3 Li and Hg 3 Al 3 Be + complexes, which also possess corresponding aromatic characters. [ABSTRACT FROM AUTHOR]

The molecular structures, stabilities, and electronic properties of the bare and complex (with group IA/IIA metals) Os 3 2+/0/2− clusters have been investigated systematically using the density-functional theory (DFT) B3LYP method. It is found that the non-linear structures in their heptet states are energetically favored for these bare and complex osmium trimers, i.e. ( 7 A′, C s ), ( 7 A 2 , C 2v ) and ( 7 A″, C s ) for bare Os 3 2+/0/2− respectively, and as ( 7 A′, C s ) and ( 7 B 1 , 7 B 2 , C 2v ) for isoelectronic (as compared to Os 3 2− ) pyramidal Os 3 M −/0 and bipyramidal Os 3 M 2 0/2+ (M = Li, Na, K and Be, Mg, Ca) complexes. The detailed molecular orbital (MO) were analyzed. The ground-states of bare Os 3 2+/0/2− clusters were observed to possess the multiple (partial σ- and partial δ-) aromaticity. The Os 3 2− motif structure was perfectly preserved in these pyramidal and bipyramidal all-metal complexes, which also possess corresponding d-orbital aromatic character. [ABSTRACT FROM AUTHOR]

The structural stability, electronic properties, and aromaticity of osmium low-nitride Os 3 N 3 +/− clusters have been investigated systematically using density functional theory (DFT) B3LYP methods. The calculations reveal that five types of σ-tangential (σ t ), σ-radial (σ r ), π-tangential (π t ), π-radial (π r ), and δ-bonding interaction exist in the planar regular hexagonal Os 3 N 3 + (D 3h , 7 A 1 ′) cation and Os 3 N 3 − (D 3h , 5 A 1 ′) anion. The detailed molecular orbitals (MOs) were analyzed. Simultaneously, the Os 3 N 3 + (D 3h , 7 A 1 ′) cation and Os 3 N 3 − (D 3h , 5 A 1 ′) anion possess triply (σ-, π- and δ-) aromatic character. The structural stabilities should be attributed to powerful five types of d-orbital bonding interaction and triple (σ-, π-, and δ-) aromaticity for the Os 3 N 3 + (D 3h , 7 A 1 ′) and Os 3 N 3 − (D 3h , 5 A 1 ′) clusters. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ascomycota and Basidiomycota had the same change trend in ginseng soils of all ages. • Soil harmful microbes predominate as culture time increased in ginseng. • Enhanced synergy of pathogenic bacteria with the extension of cultivation time. • Decreased amino acid synthesis and physiological metabolism in aged ginseng soils. • Soil pH was a driver of microbial community structure in cultivated ginseng soil. Changes in the microbial community are considered important factors affecting the yield and quality of ginseng cultivated in farmland, while the characteristics of the change in the microbial community of the soil before and after cultivation of ginseng in farmland are not well understood. Here, we aimed to fill this research gap by comparing the differences in soil nutrients and microbial communities between continuously cultivated ginseng soils for 1-, 2-, 3- and 5-year-old ginseng soils and corresponding uncultivated ginseng soils. The soil properties (pH, total soil organic carbon (TOC) content and total nitrogen (TN) content) of aged ginseng soil (3- and 5-year-old) were significantly reduced compared with those of the control soil after ginseng was cultivated in farmland. With the exception of 2-year-old ginseng, soil bacterial richness and diversity were higher in different ages of cultivated ginseng soils than in the control soil, while fungal diversity decreased in aged ginseng soil and increased in young ginseng soil (1- and 2-year-old). Ascomycota and Basidiomycota showed a consistent increasing/decreasing trend in cultivated ginseng soils of all ages compared to the control. In addition, ginseng cultivation resulted in a substantial decrease in the complexity of soil bacterial networks but a slight decrease in the complexity of fungal networks. The results from the linear discriminant size effect (LEfSe) analysis showed that beneficial microorganisms were biomarkers of the young ginseng soil, including Nitrosospira , Cephalotrichum and Humicola , while harmful microorganisms were biomarkers of aged ginseng, such as Plectosphaerella , Cladosporium and Alternaria. PICRUSt2 analysis revealed that the increase in the incidence of ginseng disease with continuous cultivation time may be related to the decreases in amino acid synthesis and physiological metabolism and the increase in fungal saprophytes. Soil pH was the most common and best predictor of bacterial and fungal community structure, followed by TOC and ammonium nitrogen (NH 4 +-N) contents. Meanwhile, the decreased of soil pH, TOC and AK may be the driving factors for the growth of ginseng soil pathogens. Overall, this study revealed the changing ginseng rhizosphere soil microbial community at different continuous cultivation times, provided a theoretical basis for ginseng cultivation, and promoted the development of medicinal plants such as ginseng. [ABSTRACT FROM AUTHOR]

The structures, stabilities and chemical bonding in the mercuric low-borides Hg 3 B 3 +/−/3− clusters are investigated using density functional theory (DFT) calculations. The extensive search for the global minimum structures of Hg 3 B 3 +/−/3− at the DFT/B3LYP level of theory revealed that the ground-state for the Hg 3 B 3 + cation is a singlet state 1 A 1 ′ with the D 3h symmetry, the ground-state for the Hg 3 B 3 − anion is a singlet state 1 A 1 with the C 2v symmetry, and the ground-state for the Hg 3 B 3 3− cluster is a triplet state 3 B 2 with the C 2v symmetry. A detailed molecular orbital (MO) analysis reveals that the Hg 3 B 3 + (D 3h , 1 A 1 ′) cation possesses the double σ - ( σ t and σ r ) aromaticity, which is responsible for a planar regular hexagonal structure D 3h ( 1 A 1 ′) of Hg 3 B 3 + and perfect triangular Hg 3 framework, respectively. The Hg 3 B 3 − (C 2v , 1 A 1 ) anion possesses the multiple ( σ - and π-) aromaticity, which is responsible for a planar regular hexagonal structure C 2v ( 1 A 1 ) of Hg 3 B 3 − and the Hg 3 B 3 3− (C 2v , 3 B 2 ) anion possesses also the multiple ( σ- and π-) aromaticity, which is responsible for a planar regular hexagonal structure C 2v ( 3 B 2 ) of Hg 3 B 3 3− and perfect triangular Hg 3 framework, respectively. We search the hexagonal pyramidal-type Hg 3 B 3 X (X = Li, Na and K) and Hg 3 B 3 Mg + complexes, which containing Hg 3 B 3 − (C 2v , 1 A 1 ) ligand to reveal that Hg 3 B 3 − (C 2v , 1 A 1 ) structural unit was preserved preferably in Hg 3 B 3 X (C 3v , 5 A 2 ) (X = Li, Na and K) and Hg 3 B 3 Mg + (C 3v , 5 A 2 ) complexes. [ABSTRACT FROM AUTHOR]

Granulocyte colony-stimulating factor (G-CSF) has been widely accepted as a mediator of T cell tolerance. The immune modulatory effect of G-CSF on T cells is believed to be mediated exclusively through other effector cells, such as monocytes, tolerogenic dendritic cells (DC), and myeloid-derived suppressor cells. Recent advances confirmed the direct effects of G-CSF in inducing immune tolerance of T cells through the G-CSF-G-CSF receptor pathway and related molecular mechanisms. This review aims to summarize the findings associated with the direct and indirect mechanisms for T cell tolerance induced with G-CSF. The role of G-CSF in preventing graft-versus-host disease (GVHD) and in treating autoimmune diseases (ADs) is also discussed. It is conceivable that G-CSF and immune cell compositions, such as tolerogenic DC and CD4 + CD25 + Foxp3 + T cells, modulated by G-CSF could become an integral part of the immunomodulatory therapies against GVHD and ADs in the future. [ABSTRACT FROM AUTHOR]

A novel amphiphilic photo-degradable hyperbranched polymer was reported at the first time. The hyperbranched o -nitrobenzyl containing poly(amino ester)s (HPAE) were prepared by one-pot Michael addition polymerization. The photo-induced degradation of hyperbranched poly(amino ester)s was confirmed by gel permeation chromatography (GPC) and UV- vis spectra. Bioinspired phosphorylcholine grafted HPAE (HPAE-PC) was synthesized via thiol-ene click chemistry. HPAE-PC can self-assemble to micelles and the micelles could be disassembled under UV irradiation because of the photo-degradation of HPAE. HPAE-PC micelles were used to load anticancer drug Doxorubicin (DOX). In vitro drug release studies showed that the release of DOX was much faster in the presence of UV irradiation than that without UV irradiation. The fluorescence microscope results indicated that DOX-loaded micelles exhibited faster drug release in A549 cells after UV irradiation. Moreover, the DOX-loaded HPAE-PC micelles under UV irradiation exhibited better anticancer activity against A549 cells than that of the nonirradiated ones. The novel amphiphilic photo-degradable hyperbranched polymers can be used to construct spatiotemporal on-demand drug delivery system for cancer therapy. [ABSTRACT FROM AUTHOR]

Phenoloxidase (PO) is a crucial component of the insect immune response against microbial infection. In the tobacco hornworm Manduca sexta , PO is generated from its precursor proPO by prophenoloxidase activating proteases (PAPs) in the presence of two noncatalytic serine protease homologs (SPHs). cDNA cloning and genome analysis indicate that SPH1a (formerly known as SPH1), SPH1b, SPH4, SPH101, and SPH2 contain a clip domain, a linker, and a protease-like domain (PLD). The first 22 residues of the SPH1b, SPH4, and SPH101 PLDs are identical, and differ from SPH1a only at position 4, Thr154 substituted with Asn154 in SPH1a. While the sequence from Edman degradation was used to establish PAP cofactor as a high M r complex of SPH1a and SPH2, this assignment needed further validation, especially because SPH1b mRNA levels are much higher than SPH1a ′s and better correlate with SPH2 transcription. Thus, here we determined expression profiles of these SPH genes in different tissues from various developmental stages using highly specific primers. High levels of SPH1b and SPH2 proteins, low SPH4, and no SPH1a or SPH101 were detected in hemolymph from larvae in the feeding, wandering and bar stages, pupae, and adults by targeted LC-MS/MS analysis, based on unique peptides from the trypsin-treated SPHs. We expressed the five proSPHs in baculovirus-infected Sf 9 cells for use as standards to identify and quantify their counterparts in plasma samples. Moreover, we tested their cleavage by PAP3 and efficacy of the SPH1a, 1b, 4, and 101 as SPH2 partners in PAP3-mediated proPO activation. PAP3 processed proSPH1b and 101 more readily than proSPH1a and 4; PAP3 activated proPO more efficiently in the presence of SPH2 with SPH101 or SPH1b than with SPH1a or SPH4. These results generally agree with their order of appearance or sequence similarity: SPH101 > SPH1b (98%) > SPH1a (90%) > SPH4 (83%). In other words, likely due to positive selection, products of the newly duplicated genes (SPH1b and SPH101) are more favorable substrates of PAP3 and better SPH2 partners in forming a high M r cofactor than SPH1a or SPH4 is. Electrophoresis on native gel and immunoblot analysis further indicated that SPH101 or 1b form high M r complexes more readily than SPH1a or 4 does. In comparison, SPH2 showed a small mobility decrease and then increase on native gel after PAP3 cleavage at the first site. Since the natural cofactor in bar-stage hemolymph is complexes of SPH1 and 2 with an average M r of 790 kDa, PAP3-activated SPH2 may associate with the higher M r SPH1b scaffolds to form super-complexes. Their structures and formation in relation to cleavage of SPH1b at different sites await further exploration. [Display omitted] • Phylogenetic relationships of the five SPH genes lead to a functional hypothesis confirmed by biochemical analyses. • Four SPHI variants (1a, 1b, 4, and 101) can form complexes with SPH2 to act as cofactors for proPO activation. • Cleavage efficiency and cofactor activity of SPH1b and 101 are higher than SPH1a or 4, consistent with positive selection of the duplicated genes. • The cofactor formation may involve multiple cleavages of proSPHI to yield high M r scaffolds for SPHII units to associate. [ABSTRACT FROM AUTHOR]

Highlights: [•] We studied the [Hf3F3]−, [Hf3F3Y]+ (Y=Be and Mg), [Hf3F3X2]+ (X=Li, Na, and K) clusters. [•] The [Hf3F3]− (D3h, 1 ) anion exhibits the multiple (δ- and π-) aromaticity. [•] The [Hf3F3Y]+ and [Hf3F3 X2]+ complexes possess the multiple (δ- and π-) aromaticity. [Copyright &y& Elsevier]

Abstract: Reversibly light-responsive and biocompatible micelles with an appropriate size were constructed from an amphiphilic spiropyran-containing hyperbranched polyphosphate (denoted as HPHEEP-SP). The polymer was conveniently synthesized based on the modification of a biodegradable hyperbranched polyphosphate with carboxyl-containing spiropyran molecules. HPHEEP-SP can self-assemble to biocompatible micelles with an average diameter of 186.3 nm and a critical micelle concentration of 0.052 mg mL−1. After 5 min of UV irradiation, the diameter of the micelles decreased gradually to about 100 nm, which is ascribed to the transformation of hydrophobic spiropyran to hydrophilic merocyanine. Subsequent exposure the micelles to visible light, the diameter of the micelles was restored. Model drug coumarin 102 was then encapsulated into the micelles successfully. Light-controlled release and re-encapsulation behaviours were lastly demonstrated by fluorescence spectroscopy. This study provides a convenient way to construct smart nanocarriers for controlled release and re-encapsulation of hydrophobic drugs. [Copyright &y& Elsevier]

Abstract: Investigation of equilibrium geometries, total energies, harmonic vibrational frequencies, and nucleus-independent chemical shifts (NICS) of the low-lying states for the planar quadrilateral CN2O2− dianion, alkali metal MCN2O− (M=Li, Na, K, Rb, and Cs) clusters, and alkali earth metal MCN2O (M=Be, Mg, Ca, Sr, and Ba) clusters were done with two density functional theory (DFT) methods. The calculations reveal that the planar quadrilateral CN2O2− dianion can coordinate with metal atoms to form the pyramidal MCN2O− and MCN2O complexes maintaining the planar quadrilateral CN2O2− dianion structure. From structural and electronic criteria, the presence of six delocalized π electrons (satisfying the 4n +2 electron counting rule), and maintaining its structural and electronic integrity inside the MCN2O− and MCN2O clusters confirm that the planar quadrilateral CN2O2− dianion exhibits characteristics of π-aromaticity. [ABSTRACT FROM AUTHOR]

Abstract: Reversibly photo-cross-linkable pH-responsive block copolymer poly(ethylene oxide)-b-poly((2-(diethylamino)ethyl methacrylate-co-4-methyl-[7-(methacryloyl)oxyethyloxy] coumarin)) (PEO-b-P(DEA-co-CMA)) was synthesized via atom transfer radical polymerization (ATRP). Block copolymer nanogels could be easily prepared by first photo-cross-linking of the micelles at pH>7 and then adjusting the solution to pH<7. The photo-cross-linking was proved to be reversibly controlled under alternative irradiation of UV light at 365nm and 254nm. As a result, the cross-linking degrees and sizes of the nanogels can be easily controlled by alternatively UV light irradiation. Finally, the nanogels can serve as nanoreactors for the synthesis of gold nanoparticles. The protonated DEA units were first coordinated with HAuCl4, and then the electrostatically bounded AuCl4− anions were reduced to gold nanoparticles by NaBH4. The nanogel-supported gold nanoparticles were used in chemical catalysis. The pH-responsive photo-cross-linked nanogels have been characterized using dynamic light scattering, transmission electron microscopy, UV–vis spectra and 1H NMR spectroscopy measurements, respectively. [Copyright &y& Elsevier]

Abstract: Phenylboronic acid-containing thermo-responsive block copolymer, poly(ethylene oxide)-b-poly(methoxydi(ethylene glycol) methacrylate-co- aminophenylboronic acid ethyl methacrylate) (PEO-b-P(DEGMMA-co-PBAMA)), was employed to investigate the multiple micellization and dissociation transitions. The unique sugar- and pH-responsive properties of phenylboronic acid were interesting to provide two parallel approaches to tune the critical micellization temperature (CMT) and multiple micellization of thermo-responsive block copolymer. The block copolymers were molecularly soluble below 21 °C and underwent micellization above 21 °C at pH 8.7. After glucose was added at 24 °C, hydrophobic phenylboronic acid was changed to hydrophilic boronate–glucose complex and the CMT of the thermo-sensitive block was increased which caused the dissociation of micelles. In parallel, if the solution pH was increased from 8.7 to 11 at 25 °C, micelles were disrupted because of the formation of hydrophilic phenylboronate anion, which elevated the CMT of the thermo-sensitive block polymer. The introduction of phenylboronic acid groups into the thermo-responsive block copolymers provides a novel approach to tune the multiple micellization and dissociation transitions that might have great potentials in biomedical applications. [Copyright &y& Elsevier]