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The solubilities of benzoic acid and its nitrated derivatives (3-nitrobenzoic acid and 3,5-dinitrobenzoic acid) in seven pure solvents—water, methanol, ethanol, acetonitrile, dichloromethane, toluene, and ethyl acetate—were determined experimentally over a temperature range from 273.15 K to 323.15 K under 101.3 kPa. The solubility of the above substances in these solvents increased with temperature. The solubility values of benzoic acid in these seven solvents follow the following order: ethanol > ethanol > acetonitrile > ethyl acetate > dichloromethane > toluene > water, while the solubility values of its nitrification derivatives in these seven solvents follow the following order: methanol > ethanol > ethyl acetate > acetonitrile > dichloromethane > toluene > water. The solubility of benzoic acid, 3-nitrobenzoic acid, and 3,5-dinitrobenzoic acid were significantly different in the same solvent. The solubilities obtained are very helpful in improving the recrystallization and yields of 3-nitrobenzoic acid and 3,5-dinitrobenzoic acid.

The efficacy of free radical-based therapeutic strategies is severely hindered by nonspecific accumulation, premature release and glutathione (GSH) scavenging effects. Herein, a tumor microenvironment-responsive MPDA/AIPH@Cu-TA@HA (abbreviated as MACTH) nanoplatform was constructed by coating Cu

We reported the synthesis of a tris(triazolylmethyl)amine (TTA)-bridged organosilane, functioning as Cu(I)-stabilizing ligands, and the installation of this building block into the backbone of mesoporous organosilica nanoparticles (TTASi) by a sol-gel way. Upon coordinating with Cu(I), the mesoporous CuI-TTASi, with a restricted metal active center inside the pore, functions as a molecular-sieve-typed nanoreactor to efficiently perform Cu(I)-catalyzed alkyne-azide cycloaddition (CuAAC) reactions on small-molecule substrates but fails to work on macromolecules larger than the pore diameter. As a proof of concept, we witnessed the advantages of selective nanoreactors in screening protein substrates for small molecules. Also, the robust CuI-TTASi could be implanted into the body of animal models including zebrafish and mice as biorthogonal catalysts without apparent toxicity, extending its utilization in vivo ranging from fluorescent labeling to in situ drug synthesis.

Lysosome, an organelle which contains a number of hydrolases and hydrogen ions, plays a crucial role in cellular survival and apoptosis. If selectively destroy lysosomes membrane, inner hydrolases and hydrogen ions will leak and induce cell death. In this work, three lysosome-targeting fluorescent probes (HCL 1-3, heptamethine cyanine lysosomal-targeting probe) were designed, synthesized and developed for photodynamic therapy. Piperazine and N, N-dimethyl structures made HCL 1-3 have good lysosome targeting ability while Pearson's correlation coefficients reached 0.85, 0.87 and 0.78. It can be concluded from MTT test, HCL 1-3 have high photo cytotoxicity and low dark cytotoxicity from MTT test. Calcein/PI staining assays also supported cytotoxicity of HCL 1-3 under light conditions. In vivo experiments, HCL 2 accumulated in tumor and a strong fluorescence signal was observed at 12 h post injection. All results showed that our experiments provide help and new ideas for cyanine dyes in cancer treatment.

Recently, the toxic hydroxyl radical (·OH) has received wide interest for inducing cell apoptosis by increasing the intracellular reactive oxygen species (ROS) levels. Herein, a cationic polymer (MV-PAH) was rationally synthesized, and a new pH-responsive nanoreactor (DOX@Fe-MOF@PEM) was modified with the prepared cationic polymer MV-PAH multilayers by layer-by-layer (LBL) technique. The polyelectrolyte multilayer (PEM) disassembled and notably enhanced drug delivery in the weak acid environment of the tumor cell. In the cytotoxicity and apoptosis experiments, DOX@Fe-MOF@PEM revealed an advanced repression of cancer. The H2O2 induced by DOX and MV-PAH could be catalyzed to generate hypertoxic ·OH through intracellular iron ions based on a Fenton-like reaction, which thereby improved the anticancer effect of DOX. This realistic strategy may create a potential way to provide a combination of ROS and chemotherapy to improve the anti-cancer effect.

The delivery of salicylic acid or its derivatives to tumor tissue in the form of nanomedicine is critical for the studies on their potential synergistic mechanism in tumor therapy and chemoprevention considering the dangerous bleeding in the high-dose oral administration. To deepen the understanding of their role in adjusting immunosuppressive tumor microenvironment (ITM), herein, we firstly developed a hypoxia-sensitive Fe-5,5'-azosalicylic acid nanoscale coordination polymer nanomedicines (FeNCPs) via a "old drugs new tricks" strategy for synergistic chemodynamic therapy (CDT) and remodulation of ITM to elevate antitumor immunotherapy effect. PEGylated FeNCPs could be reductively cleaved to release 5-aminosalicylic acid (5-ASA) and ferric ions by azo-reductase under hypoxic conditions, which could induce tumor cell death by Fenton reaction-catalysis enhanced CDT and 5-ASA-converted carboxylquinone to promote the production of •OH. Meanwhile, cyclooxygenase-2 (COX-2) and its enzymatic product prostaglandin E

The integration of metal-ion therapy and hydroxyl radical (˙OH)-mediated chemodynamic therapy (CDT) holds great potential for anticancer treatment with high specificity and efficiency. Herein, Ag nanoparticles (Ag NPs) were enveloped with Cu2+-based metal-organic frameworks (MOFs) and further decorated with hyaluronic acid (HA) to construct a glutathione (GSH)-activated nanoplatform (Ag@HKU-HA) for specific chemodynamic/metal-ion therapy. The obtained nanoplatform could avoid the premature leakage of Ag in circulation, but realize the release of Ag at the tumor site owing to the degradation of external MOFs triggered by Cu2+-reduced glutathione. The generated Cu+ could catalyze endogenous H2O2 to the highly toxic ˙OH by a Fenton-like reaction. Meanwhile, Ag NPs were oxidized to toxic Ag ions in the tumor environment. As expect, the effect of CDT combined with metal-ion therapy exhibited an excellent inhibition of tumor cells growth. Therefore, this nanoplatform may provide a promising strategy for on-demand site-specific cancer combination treatment.

Twenty reported compounds (1–20), including four sterols, five triterpenes, two anthraquinones, three chromones, two stilbenes and four flavonoids, were obtained from Fallopia aubertii by phytochemical methods. Their structures were confirmed on the basis of spectroscopic methods. Among them, nine compounds were firstly reported from the genus Fallopia, while eight of them were obtained from this species for the first time. In addition, this study discussed the relatonships between F. aubertii and some plants of Polygonaceae family.

An improved analytical model for vertical borehole ground heat exchanger (BHE) which takes into account effect of groundwater flow in multiple-layer geologies is applied to simulate and analyze the long-term temperature response of soil around BHE with the unbalanced seasonal dynamic load. The present model was validated by experiment for a single borehole with good agreement, and it can find that the average of temperature integral along the borehole wall depth is taken as the representative temperature of the borehole wall will be more reasonable. Moreover, the influence of groundwater flow velocity on soil temperature around the borehole was investigated, the results show that the deformation of plane temperature field caused by groundwater advection, as equivalent velocity reach a certain order of magnitude, groundwater flow can effectively alleviate the heat (cold) accumulation. Finally, the temperature change of soil around borehole at different operation time was simulated, results indicate that the higher the groundwater velocity is, the faster time make temperature field to achieve stability. This analytical model provides better flexibility and versatility to research further the effect of groundwater flow in layered geologies.

In this paper, the energy efficiency of multi-input single-output and orthogonal frequency division multiplexing (MISO-OFDM) communication systems with power and capacity constraints is investigated. By formulating the power allocation problem of MISO-OFDM communication systems, the minimum subchannel transmission power is analyzed with power and capacity constraints. Simulation results indicate that there exists a specific minimum subchannel capacity threshold. Moreover, the energy efficiency of MISO-OFDM communication systems starts to increase only when the minimum subchannel capacity exceeds the specific threshold.

In this paper, the uplink energy efficiency and uplink outage probability for two-tier cellular access networks (TTCANs) are investigated. To model of the uplink energy efficiency and uplink outage probability in TTCANs, a closed-form expression of signal-to-interference ratio (SIR) is derived by considering the on/off states of femtocell access points (APs). Moreover, a second order kernel function is firstly used to solve the analytical interference model with femtocell APs turning on in TTCANs. Simulation results show that femtocell user's intensity has great impact on the uplink energy efficiency and uplink outage probability in a TTCAN. These results provide some guidelines for developing new energy saving schemes in practical TTCANs deployment.

In this paper, the relationship between the energy efficiency and spectrum efficiency in a two-cell cellular network is obtained, and the impact of multi-antenna on the energy efficiency of cellular network is analyzed and modeled based on two-state Markovian wireless channels. Then, the energy efficiency of multi-cell cellular networks with co-channel interference is investigated. Simulation results verify the proposed model and the energy-spectrum efficiency tradeoffs in cellular networks with multi-antenna and co-channel interference.