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A tetracationic macrocycle can include clinically used photodynamic agents, alleviating their posttreatment phototoxicity and maintaining their photodynamic efficacy.

Since 1995, photodynamic therapy (PDT) has been utilized as an effective method for cancer treatment. However, the residues of photosensitizers in the normal tissues after PDT can be activated by sunlight to cause severe skin phototoxicity, for which currently there are no clinical solutions. As a result, post-PDT patients need to remain out of sunlight for up to five weeks, which produces great living and mental burdens for patients. Herein, we report that a biocompatible porous organic polymer (POP) with average 3.1 nm porosity is able to suppress the skin phototoxicity of clinically used porphyrin-based photodynamic agents (PDAs), including Photofrin, Talaporfin and Hiporfin, through an adsorption-elimination mechanism. Fluorescence titration and dialysis experiments show that POP can adsorb and retain the PDAs at a micromolar concentration. In vivo experiments demonstrate that POP can significantly suppress the skin phototoxicity caused by all the three PDAs without reducing their PDT efficacy. STATEMENT OF SIGNIFICANCE: Up to now, no efficient clinical treatment for the inhibition of post-PDT phototoxicity of clinically used porphyrin-based PDAs is available. In the manuscript, a water-soluble cationic porous organic polymer has been revealed to include three clinically used PDAs. In vivo experiments show that this inclusion remarkably reduces the content of PDAs in mouse skins, leading to significant alleviation of their post-PDT phototoxicity without no negative effect on their PDT efficacy. Thus, this work provides a strategy for overcoming the drawback of clinically used photodynamic agents.

A three-dimensional flexible organic framework FOF-1 has been synthesized from the condensation of a tetratopic acylhydrazine and a rigid 4,4′-diphenyl-4,4′-bipyridinium dialdehyde in water through the quantitative formation of hydrazone bond. FOF-1 is further applied to construct a polycatenane framework FOF-pc-1 through the quantitative cucurbit[7]uril encapsulation for the diphenylbipyridinium subunits of the framework by making use of the dynamic nature of the hydrazone bond in water. The bipyridinium subunits in both frameworks can be reduced their radical cation counterparts to produce conjugated radical cation-linked dynamic organic frameworks rc-FOF-1 or rc-FOF-pc-1. Polycatenation is revealed to enhance the stability of the dynamic frameworks in water, whereas depolycatenation can be reached for both FOF-pc-1 and rc-FOF-pc-1 by using a ferrocene guest to form a more stable complex with CB[7].

Bacterial lipopolysaccharides (LPS, endotoxins) cause sepsis that is responsible for a huge amount of mortality globally. However, their neutralization or detoxification remains an unmet medical need. We envisaged that cationic organic frameworks with persistent hydrophobic porosity may adsorb and thus neutralize LPS through a combination of cooperative ion-pairing electrostatic attraction and hydrophobicity. We here report the preparation of two water-soluble flexible organic frameworks (FOF-1 and FOF-2) from tetratopic and ditopic precursors through quantitative formation of hydrazone bonds at room temperature. The two FOFs are revealed to possess hydrodynamic diameters, which range from 20 to 120 nm, depending on the concentrations. Dynamic light scattering and isothermal titration calorimetric and chromogenic limulus amebocyte lysate experiments indicate that both frameworks are able to adsorb and thus reduce the concentration of free LPS molecules in aqueous solution, whereas cytokine inhibition experiments with RAW264.7 support that this adsorption can significantly decrease the toxicity of LPS. In vivo experiments with mice (five males per group) show that the injection of FOF-1 at a dose of 0.6 mg/kg realizes the survival of all of the mice administrated with LPS of the d-galactosamine (d-Gal)-sensitized absolute lethal dose (LD

A water-soluble porous supramolecular polymer is assembled through a CB[8]-based 2 + 2 host–guest binding motif, which can greatly increase the efficiency of photocatalysis.

Key management is the base of wireless sensor network security, key pre-distribution way is a high feasibility method in key management. The network connectivity rate, resilience against node capture and the storage consumption are important performance indicators in key pre-distribution way. However, most of the existing key pre-distribution schemes of wireless sensor network have the problems of low connectivity rate ， large storage consumption or poor resilience against node capture .On the basis of Overlap-Key-Sharing (OKS) management scheme and the group-based model of Wenliang Du and Donggang Liu et, an improved Overlap-Key-Sharing key management scheme is proposed. The management scheme has little storage consumption and good resilience against node capture. In this paper, we mainly do some analyses and evaluations on a basic random key pre-distribution scheme (E-G scheme) which is proposed by Eschenauer and Gligor et and the improved Overlap-Key-Sharing key management scheme. Result analyses show that under the same network connectivity rate, compared to E-G management scheme, the improved scheme has better resilience against node capture and the smaller storage consumption.

Treatment responses of N 0 stage nasopharyngeal carcinoma were firstly analyzed comprehensively to evaluate long term outcomes of patients and identify prognostic factors. A total of 610 patients with N 0 NPC, undergoing definitive radiotherapy to their primary lesion and prophylactic radiation to upper neck, were reviewed retrospectively. Concomitant chemotherapy was administrated to 65 out of the 610. Survival rates of the patients were calculated using the Kaplan-Meier method and compared by log-rank test. Prognostic factors were identified by the Cox regression model. The study revealed the 5-year and 10-year overall, disease-free, disease-specific, local failure-free, regional failure-free, locoregional failure-free and distant metastasis-free survival rates to be 78.7% and 66.8%, 68.8% and 55.8%, 79.9% and 70.4%, 81.2% and 72.5%, 95.8% and 91.8%, 78.3% and 68.5%, 88.5% and 85.5%, respectively. There were 192 patients experiencing failure (31.5%) after radiotherapy or chemoradiotherapy. Of these, local recurrence, regional relapse and distant metastases as the first event of failure occurred in 100 (100/610, 16.4%), 15(15/610, 2.5%) and 52 (52/610, 8.5%), respectively. Multivariate analysis showed that T stage was the only independent prognostic factor for patients with N 0 NPC (P=0.000). Late T stage (P=0.000), male (P=0.039) and anemia (P=0.007) were independently unfavorable factors predicting disease-free survival. After treatment, satisfactory outcome wasgenerally achieved in patients with N 0 NPC. Local recurrence represented the predominant mode of treatment failure, while T stage was the only independent prognostic factor for overall survival. Late T stage, male gender, and anemia independently predicted lower possibility of the disease-free survival.