Novel multi-analyte responsive ionic supramolecular gels based on pyridinium functionalized-naphthalimide

A novel ionic supramolecular gel (is-G) is synthesized using N-(pyridinium-4-yl)-naphthalimide (G1) and n-pentanoic acid. By rationally introducing competitive coordination into is-G, two ion coordinated ionic supramolecular gels is-IG and is-FeG (coordinated with I^- and Fe³⁺, respectively) are obtained. is-IG could fluorescently "turn-on" detect Hg²⁺ and l-Arg with specific selectivity, whereas, is-FeG could accurately identify l-Ser via fluorescence in water. Moreover, ion or amino acid responsive films based on these ionic supramolecular gels are prepared. These ionic supramolecular gels and films could act as multi-analyte detection materials as well as fluorescent display materials.

Toroidal resonance based optical modulator employing hybrid graphene-dielectric metasurface

In this paper, we demonstrate the combination of a dielectric metasurface with a graphene layer to realize a high performance toroidal resonance based optical modulator. The dielectric metasurface consists of two mirrored asymmetric silicon split-ring resonators (ASSRRs) that can support strong toroidal dipolar resonance with narrow line width (~0.77 nm) and high quality (Q)-factor (~1702) and contrast ratio (~100%). Numerical simulation results show that the transmission amplitude of the toroidal dipolar resonance can be efficiently modulated by varying the Fermi energy EF when the graphene layer is integrated with the dielectric metasurface, and a max transmission coefficient difference up to 78% is achieved indicating that the proposed hybrid graphene/dielectric metasurface shows good performance as an optical modulator. The effects of the asymmetry degree of the ASSRRs on the toroidal dipolar resonance are studied and the efficiency of the transmission amplitude modulation of graphene is also investigated. Our results may also provide potential applications in optical filter and bio-chemical sensing.

Prazosin during threat discrimination boosts memory of the safe stimulus

The α-1 adrenoreceptor antagonist prazosin has shown promise in the treatment of post-traumatic stress disorder (PTSD) symptoms, but its mechanisms are not well understood. Here we administered prazosin or placebo prior to threat conditioning (day 1) and tested subsequent extinction (day 2) and reextinction (day 3) in healthy human participants. Prazosin did not affect threat conditioning but augmented stimulus discrimination during extinction and reextinction, via lower responding to the safe stimulus. These results suggest that prazosin during threat acquisition may have influenced encoding or consolidation of safety processing in particular, subsequently leading to enhanced discrimination between the safe and threatening stimuli.

A novel supramolecular organogel based on acylhydrazone functionalized pillar[5]arene acts as an I- responsive smart material

A novel organic gelator (PZ) has been synthesized by rationally connecting a pillar[5]arene moiety and a bis(hexadecyloxy)phenyl functionalized acylhydrazone moiety. PZ could self-assemble into a supramolecular polymer and form a stable organogel (OPZ) in cyclohexanol by multi-self-assembly driving forces such as C-Hπ, ππ, vdW and hydrogen bonding interactions. The organogel (OPZ) shows blue aggregation-induced emission (AIE). Interestingly, the organogel OPZ could sense iodide ions (I^-) in the gel-gel state with high selectivity and sensitivity. The detection limit of OPZ for I^- is 9.4 × 10^-8 M, indicating high sensitivity to I^-. Furthermore, a thin film based on OPZ was prepared, which could be used as a smart material for the detection of I^- as well as a fluorescent security display material.

A novel supramolecular polymer gel based on naphthalimide functionalized-pillar[5]arene for the fluorescence detection of Hg2+ and I- and recyclable removal of Hg2+via cation-π interactions

The development of novel materials for the detection and removal of Hg²⁺ is a very important issue due to the acute toxicity of Hg²⁺. Herein, a novel supramolecular polymer P5BD-DPHB has been constructed by the collaboration of a naphthalimide functionalized-pillar[5]arene host (P5BD) and a bis-bromohexane functionalized-pillar[5]arene guest (DPHB). P5BD-DPHB could form a stable supramolecular gel (P5BD-DPHB-G). Interestingly, P5BD-DPHB-G shows selective fluorescent "turn-on" detection for Hg²⁺via cation-π interactions with high selectivity and sensitivity. Furthermore, the Hg²⁺ coordinated supramolecular gel P5BD-DPHB-HgG can detect I^- successively. The detection limits for Hg²⁺ and I^- are 1.65 × 10^-9 and 1.84 × 10^-8 mol L^-1, respectively. Even more significantly, the xerogel of P5BD-DPHB-G could remove Hg²⁺ from aqueous solution with excellent recyclability and ingestion capacity, and with a Hg²⁺ removal rate of 98%.

Preoperative evaluation and surgical technique of functional and cosmetic aspects in zygomatic complex fracture patients

The zygomatico-maxillary complex functions as the principle buttress of the face and is the cornerstone to an individual’s aesthetic appearance. Its fracture not only creates cosmetic deformities owing to its position and facial contour, but can also cause disruption of ocular and mandibular functions. The aim of this study was to evaluate the quality, efficacy and impact of internal fixation of zygomatic complex fractures on functional and cosmetic outcomes. A prospective study was carried out on 100 patients who were divided according to the classification and the severity of injury. Subjective evaluation was submitted based on the patient’s perception of signs and symptoms in the preoperative and postoperative periods. Intraoperative and postoperative assessment of bone reduction quality was made according to the type of the fracture and related difficulties; also, the difference between these groups was observed as functional and esthetic outcome. To optimize the treatment of zygomatic bone fractures, a pre-designed questionnaire was used for subjective evaluation of symptoms and treatment outcome. In 70% of cases, ophthalmologic consultation was taken and was most common in type VII fractures (100% cases). Neurosensory disturbance was the most common finding (60%), followed by diplopia (56R%), pain upon mouth opening (54%) and malar depression (50%). Out of all possible 400 fracture sites in 100 patients of zygomatic complex fractures, 266 (66.5%) fractures were detected by clinical examination, in contrast to 330 (82.5%) on radiological examination, which were highest at zygomatic-maxillary buttress (93%) followed by infraorbital rim (91%) and almost equal among fronto-zygomatic site (72%) and zygomatic arch (74%). The scores from the questionnaire for annoyance were significantly higher for paraesthesia (23%) than for trismus (10%), pain (8.5%), or deformity (8.25%). Residual deformity and pain significantly influenced the total satisfaction. Conclusively, there are many treatment modalities available for zygomatic complex fractures, and the preferred methods should be selected on the basis of fracture type, fracture severity, pre-operative signs and symptoms. Regarding the requirements of fracture site exposure and actual fixation, one priority should be to minimize postoperative complications, morbidity and residual deformities.

A reminder before extinction strengthens episodic memory via reconsolidation but fails to disrupt generalized threat responses

A reminder can temporarily renew flexibility of consolidated memories, referred to as reconsolidation. Pavlovian threat-conditioning studies suggest that a reminder can renew flexibility of threat responses but that episodic memories remain stable. In contrast, outside the threat-conditioning domain, studies testing memory for word lists or stories find that a reminder can renew flexibility of episodic memory. This discrepancy in findings leaves it unclear if episodic memories reconsolidate, or only Pavlovian responses. Here we unite the different approaches in the field and show that a reminder can retroactively strengthen episodic memory for Pavlovian threat-conditioned events, but that, in contrast to threat-conditioning studies with simple sensory stimuli, extinction after a reminder fails to prevent recovery of generalized threat responses. Our results indicate the episodic memories also reconsolidate, allowing strengthening of relevant memories. These findings also suggest that generalized threat responses and episodic memories are less susceptible to be modified by reminder-interventions procedures.

Vertebral fracture in postmenopausal Chinese women: a population-based study

In a random sample of postmenopausal Chinese women, the prevalence of radiographic vertebral fractures increased from 13% between ages 50 and 59 to over 50% after age 80 years. A model with seven clinical risk factors predicted the probability of vertebral fractures as well with as without BMD and better than a model with only three risk factors. More than half an hour of outdoor activity per day might correlate with lower risk of vertebral fracture in this population.

INTRODUCTION

We aimed to describe the prevalence and develop a model for prediction of radiographic vertebral fractures in a large random sample of postmenopausal Chinese women.

METHODS

We enrolled 1760 women from an age-stratified random sample of postmenopausal women in Beijing, China. The presence of vertebral fracture was assessed by semi-quantitative grading of lateral thoracolumbar radiographs, risk factors by interview, bone mineral density (BMD) of the proximal femur and lumbar spine by dual x-ray absorptiometry (DXA), and markers of bone turnover from a fasting blood sample. Associations of these factors were analyzed in logistic models and discrimination by areas of receiver operating characteristics curves (AUC).

RESULTS

The prevalence of vertebral fracture, ranged from 13.4% ages 50 to 59 years old to 58.1% at age 80 years or older. Older age, a history of non-vertebral fracture, lower femoral neck BMD T-score, body mass index (BMI), height loss, housework, and less than half an hour of outdoor activity were significantly associated with increased probability of having a vertebral fracture. A model with those seven factors had a similar AUC with or without BMD and performed better than a simple model with three factors.

CONCLUSION

This study is from a true random sample of postmenopausal women in urban China with high response rate. The prevalence of vertebral fractures in postmenopausal women in Beijing increases from 13% under age 60 to over 50% by age 80 years. A model with seven clinical risk factors with or without BMD is better than simple models and may guide the use of spine x-rays to identify women with vertebral fractures. More than half an hour of outdoor activity might correlate with lower risk of vertebral fracture in this population.

Cannabinoid receptor agonist WIN55,212-2 and fatty acid amide hydrolase inhibitor URB597 ameliorate neuroinflammatory responses in chronic cerebral hypoperfusion model by blocking NF-κB pathways

The present study explored the protective effects of cannabinoid receptor agonist WIN55,212-2 (WIN) and fatty acid amide hydrolase inhibitor URB597 (URB) against neuroinflammation in rats with chronic cerebral hypoperfusion (CCH). Activated microglia, astrocytes, and nuclear factor kappa B (NF-κB) p65-positive cells were measured by immunofluorescence. Reactive oxygen species (ROS) was assessed by dihydroethidium staining. The protein levels of cluster of differentiation molecule 11b (OX-42), glial fibrillary acidic protein (GFAP), NF-κB p65, inhibitor of kappa B alpha (IκB-a), IκB kinase a/β (IKK a/β), phosphorylated IKK a/β (p-IKK a/β), cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), tumor necrosis factor (TNF)-α, and interleukin-1β (IL-1β) were examined by western blotting or enzyme-linked immunosorbent assay. All the protein levels of OX-42, GFAP, TNF-a, IL-1β, COX-2, and iNOS are increased in CCH rats. WIN and URB downregulated the levels of OX-42, GFAP, TNF-α, IL-1β, COX-2 and iNOS and inhibited CCH-induced ROS accumulation in CCH rats, indicating that WIN and URB might exert their neuroprotective effects by inhibiting the neuroinflammatory response. In addition, the NF-κB signaling pathway was activated by CCH in frontal cortex and hippocampus, while the aforementioned changes were reversed by WIN and URB treatment. These findings suggest that WIN and URB treatment ameliorated CCH-induced neuroinflammation through inhibition of the classical pathway of NF-κB activation, resulting in mitigation of chronic ischemic injury.

A pillar[5]arene-based multiple-stimuli responsive metal-organic gel was constructed for facile removal of mercury ions

A thioacetohydrazide functionalized pillar[5]arene was synthesized, which could further assemble into a linear supramolecular metal-organic polymer upon adding Zn²⁺. Furthermore, the obtained linear supramolecular metal-organic polymer could self-assemble to form a fluorescent supramolecular metal-organic gel at high concentration. When TBAOH was added to the viscous solution at high temperature, the obtained solution could not form a supramolecular metal-organic gel upon cooling. More importantly, when Hg²⁺ ions are added to the metal-organic gel, the strong blue fluorescence is clearly quenched, and this metal-organic gel (xerogel) could effectively remove Hg²⁺ from water. Simultaneously, a thin film based on the metal-organic gel was prepared, which was confirmed to be a convenient test kit for detecting Hg²⁺.

Crystal structure of 2,3,9,10-tetramethoxy-5,6-dihydroisoquinolino[2,1-b]isoquinolin-7-ium 5-hydroxy-3-(4-hydroxyphenyl)-4-oxo-4H-chromen-7-olate methanol solvate, C37H35N1O10

C37H35N1O10, triclinic, P1̅ (no. 2), a = 12.039(8) Å, b = 12.353(9) Å, c = 12.938(9) Å, α = 102.786(3)°, β = 111.865(6)°, γ = 105.173(7)°, V = 1610.6(19) Å3, Z = 2, Rgt(F) = 0.0567, wRref(F2) = 0.1392, T = 293 K.

Tunable graphene-based plasmonic multispectral and narrowband perfect metamaterial absorbers at the mid-infrared region

We numerically investigate the optical performance of a periodically patterned H-shaped graphene array by the finite-difference time-domain (FDTD) in the mid-infrared region. The simulated results reveal that absorption spectra of the proposed structure consist of two dramatic narrowband perfect absorption peaks located at 6.3 μm (Mode 1) and 8.6 μm (Mode 2) with high absorption coefficients of 99.65% and 99.80%, respectively. Two impressive absorption bandwidths that are the full width at half-maximum (FWHM) of the resonant frequency of 90 nm and 188 nm are obtained. The dipole resonance mode is supported by graphene ribbon at a wavelength of 6.3 μm. While the other absorption, attributed to the hybridized mode, is a new resonance that is different from the dipole resonance. The spectral position of the absorption peaks can be dynamically tuned by controlling the refractive index of the dielectric and the Fermi energy of graphene. Furthermore, we can obtain multispectral absorption peaks by applying multilayer graphene arrays. These design approaches enable us to control the number of absorption spectra and such absorbers will benefit the easy-to-fabricate nanophotonic devices for optical filtering, thermal detectors, and electromagnetic wave energy storage.

[Marine Aerosol Using On-board Aerosol Mass Spectrometry]

Marine aerosols were measured in real-time by an on-board signal particle aerosol mass spectrometer(SPAMS) over the Southeast China Sea. The chemical compositions and size distribution characteristics of aerosol particles were obtained, and the sources and ion spectra were analyzed. The results showed that particle number concentration decreased with the distance apart from the coastal area. In the coastal area, the aerosol compositions were mainly determined by the emissions of industry, such as vessel, traffic and coal combustion etc. When it was far from the continent, aerosols were mainly affected by the sea sources. Aerosol particles during the observation period disturbed singly with a peak diameter value of 0.5 μm. Most of the particles were in the size range of 0.2 μm to 0.8 μm. High signal intensity of EC with high K⁺ intensity in the positive spectrum and HSO₄^- intensity in negative spectrum was present in the marine aerosol over the coastal area. However, the signals of NO₃^- and NO₂^- were absent in the negative spectrum. The signal intensity of EC was weak in the marine aerosol over the sea area far from the coastal area. High signal intensity of Na⁺ and weak Mg⁺,Ca⁺ and NaCl⁺ signals were present in the positive spectrum, while high signal intensity of MSA^-,CN^-,O^- and HSO₄^- were present in negative spectrum which was considered to be the special ions spectrum of marine biological sources. It indicated that ambient aerosols over the observation area were influenced not only by the anthropogenic emission sources but also affected by the marine aerosol formation.

Role of biochar in biodegradation of nonylphenol in sediment: Increasing microbial activity versus decreasing bioavailability

The observed strong sorption of hydrophobic organic contaminants (HOCs) to biochar presents potential implications for HOCs bioavailability and bioaccessibility in sediments, while biochar could impact sediment microbial ecology. However, the comprehensive study on the effects of biochar on HOC biodegradation coupled with bioavailability and microbial ecology are rarely documented. In this paper, the effects of biochar on the biodegradation of nonylphenol (NP) were investigated using 3 different NP concentrations (20, 50 and 500 mg/Kg) in sediments amended with different percentage of rice straw biochar (RC). Results showed that the influence of RC on NP biodegradation varied with different NP concentrations. At low NP concentrations, RC suppressed NP biodegradation by reducing NP bioavailability, while at high NP concentrations, moderate RC addition promoted biodegradation by reducing toxicity of NP to microbes. The effects of NP on microbial community structures were significant (P < 0.01), but those of RC were not significant (P > 0.05). The RC affected microorganisms through altering NP toxicity, microbial quantity and activity, but not microbial community structures. This study indicated that there could be an optimal biochar percentage in biochar-sediment systems at different HOC concentrations, which strengthened HOC biodegradation process and accelerated biodegradation rate, forming adsorption-biodegradation coupled bioremediation.

Colorimetric and fluorescent chemosensor for highly selective and sensitive relay detection of Cu2+ and H2PO4- in aqueous media

In this manuscript, a new colorimetric and fluorescent chemosensor (T) was designed and synthesized, it could successively detect Cu²⁺ and H₂PO₄^- in DMSO/H₂O (v/v=9:1, pH=7.2) buffer solution with high selectivity and sensitivity. When added Cu²⁺ ions into the solution of T, it showed a color changes from yellow to colorless, meanwhile, the green fluorescence of sensor T quenched. This recognition behavior was not affected in the presence of other cations, including Hg²⁺, Ag⁺, Ca²⁺, Co²⁺, Ni²⁺, Cd²⁺, Pb²⁺, Zn²⁺, Cr³⁺, and Mg²⁺ ions. More interestingly, the Cu²⁺ ions contain sensor T solution could recover the color and fluorescence upon the addition of H₂PO₄^- anions in the same medium. And other surveyed anions (including F^-, Cl^-, Br^-, I^-, AcO^-, HSO₄^-, ClO₄^-, CN^- and SCN^-) had nearly no influence on the recognition behavior. The detection limits of T to Cu²⁺ and T-Cu²⁺ to H₂PO₄^- were evaluated to be 1.609×10^-8M and 0.994×10^-7M, respectively. In addition, the sensor T also could be served as a recyclable component and the logic gate output was also defined in sensing materials. The test strips based on sensor T were fabricated, which acted as a convenient and efficient Cu²⁺ and H₂PO₄^- test kits.

Abstract 3214: Systematic drug repurposing for faster cures of pediatric cancer identifies that Digoxin prolongs survival in a PDOX model of group 4 medulloblastoma

Background: Medulloblastoma (MB) is the most common malignant brain tumor of childhood. While the current standard care for MB leads to long term survival in approximately 75 % of patients; recurrent and refractory MB continues to have dismal outcomes. In addition, long term survivors face significant treatment-related sequelae especially poor neurocognitive outcomes. Drug repositioning for known drugs is a promising potential strategy not only for drug discovery but also for accelerated translation into the clinical setting. To systematically explore thousands of known drugs available, we integrated computational biology and empirical biology methods to find old drugs for new indications in MB.

Results: A non-parametric, bootstrapping based simulated annealing (NPBSA) algorithm was employed to identify driver signaling pathways for over 1,800 patients with Group 3 and Group 4 MB through an integrative analysis on their mRNA expression, DNA-copy number, DNA-methylation and DNA-seq profiles. Then, drug functional networks were constructed based on gene expression profiles under drug treatment as well as chemical structures and were clustered into drug modules with potential mechanisms of action. By evaluating targeted effects of 1,309 drugs from connectivity map database within each drug module in driver signaling pathways, we identified a group of known cardiac glycosides that top ranked among the total drug candidates for the Group 3 and 4 MB subtypes. In addition to traditional chemotherapeutic agents, members of the cardiac aminoglycoside family were repeatedly identified as potential therapeutic agents for MB. These findings were validated in multiple MB-derived cell lines which showed high rates of growth inhibition by cardiac aminoglycosides compared to controls. To evaluate if this growth inhibition in vitro correlated to prolonged survival in vivo, an extensively characterized patient-derived orthotopic-xenograft (PDOX) model of Group 4 MB (ICb-1078MB) was treated with digoxin (2 mg/kg i.p.) for 2 cycles of 14 days. Digoxin treatment significantly prolonged survival to 113 days from a median of 92 days in untreated controls (p=0.001). Histological evaluation of recurrent tumors following digoxin treatment demonstrated changes in the pattern of tumor spread, vascularity and necrosis compared to untreated controls.

Conclusions: Leveraging big data in the domains of pharmacogenomics and the notion of drug functional networks and driver signaling pathways represents a powerful tool to repurpose known drugs for new indications in pediatric cancers. Using this integrative biology approach, we identified the cardiac aminoglycosides family generally and Digoxin, specifically, as potential novel agents in the treatment of pediatric medulloblastoma

Citation Format: Lei Huang, Sarah G. Injac, Hong Zhao, Qi Lin, Mari Kogiso, Chris T. Man, Xiao-Nan Li, Ching C. Lau, Stephen T. Wong. Systematic drug repurposing for faster cures of pediatric cancer identifies that Digoxin prolongs survival in a PDOX model of group 4 medulloblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3214. doi:10.1158/1538-7445.AM2017-3214

Thermoresponsive Pickering Emulsions Stabilized by Silica Nanoparticles in Combination with Alkyl Polyoxyethylene Ether Nonionic Surfactant

We put forward a simple protocol to prepare thermoresponsive Pickering emulsions. Using hydrophilic silica nanoparticles in combination with a low concentration of alkyl polyoxyethylene monododecyl ether (C₁₂E_n) nonionic surfactant as emulsifier, oil-in-water (o/w) emulsions can be obtained, which are stable at room temperature but demulsified at elevated temperature. The stabilization can be restored once the separated mixture is cooled and rehomogenized, and this stabilization-destabilization behavior can be cycled many times. It is found that the adsorption of nonionic surfactant at the silica nanoparticle-water interface via hydrogen bonding between the oxygen atoms in the polyoxyethylene headgroup and the SiOH groups on particle surfaces at low temperature is responsible for the in situ hydrophobization of the particles rendering them surface-active. Dehydrophobization can be achieved at elevated temperature due to weakening or loss of this hydrogen bonding. The time required for demulsification decreases with increasing temperature, and the temperature interval between stabilization and destabilization of the emulsions is affected by the surfactant headgroup length. Experimental evidence including microscopy, adsorption isotherms, and three-phase contact angles is provided to support the mechanism.