Synthesis of a novel magnetic polyacrylamide coagulant and its application in wastewater purification.

In this study, a novel magnetic polyacrylamide (PAM) coagulant based on the core of magnetite (Fe3O4), with oleic acid serving as modifier and acrylamide as monomer, was synthesized to remove suspended solids in kaolin-suspended water. The composites were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, thermo gravimetric analysis and scanning electron microscopy. The results demonstrated that 82.8% of turbidity removal rate was obtained in 5 min of static settling in simulated kaolin-suspended water. This proved to be superior to that of PAM and poly aluminum chloride. Also confirmed in this study was the fact that zeta potential was significantly correlated with turbidity removal.

Porphyrin Derivative with Binary Properties of Photodynamic Therapy and Water-Dependent Reversible Photoacidity Therapy for Treating Hypoxic Tumor.

Porphyrin photosensitizers are the classic drugs in clinical photodynamic therapy (PDT), but the hypoxia of tumor environment and the rapid oxygen consumption of PDT severely weaken their therapeutic effect. A recently reported water-dependent reversible photoacidity therapy (W-RPAT) is O2-independence, providing a solution for the treatment of hypoxic tumors. In this work, TPP-O-PEG5, a porphyrin derivative with binary properties of PDT and W-RPAT, is designed and synthesized for the first time. The nanoparticles (NPs) of TPP-O-PEG5 encapsulated with DSPE-mPEG2000, an amphiphilic polymer approved by Food and Drug Administration, can simultaneously produce reactive oxygen species and H+ under irradiation of a 660 nm laser, and revert the H+ back under darkness, presenting strong phototoxicity to multiple tumor cell lines with no obvious difference between the IC50 values tested under normoxic (≈20% O2) and hypoxic (<0.5% O2) conditions. Excitingly, in vivo experiments show that the therapeutic effect of TPP-O-PEG5 NPs on large hypoxic tumors is better than that of NPe6, a clinical porphin PDT drug. This work provides a novel strategy for porphyrin photosensitizers to break through the limitation of hypoxic environment, and significantly improve the phototherapeutic effect on hypoxic tumors.

Expression of CCL2 signaling pathway genes in patients with periodontitis and atherosclerosis.

OBJECTIVE: Periodontitis and atherosclerosis are chronic inflammatory diseases characterized by leukocyte infiltration. We investigated the expression of CCL4, CCR5, c-Jun, c-Fos, NF-κB, and CCL2 as well as the possible mechanism involved in the regulation of CCL2 in human periodontitis tissues and atherosclerotic aorta based on previous research on the CCL4/CCR5/c-Jun and c-Fos/CCL2 pathway leading to CCL2 expression in collagen-induced arthritis (CIA) rat. METHODS: Sixty-five volunteers were recruited and the condition of their gingiva and coronary arteries were assessed. The subjects were divided into four groups: healthy control, chronic periodontitis (CP), coronary artery diseases (CAD), and noncoronary artery diseases (non-CAD). Total RNA was isolated from gingiva in periodontitis patients and control populations and from the aorta in patients with and without CAD. PCR was used to examine CCL4, CCR5, c-Jun, c-Fos, NF-κB, and CCL2 levels. The production of CCL2 in the gingiva and aorta was analyzed by immunostaining. RESULTS: PCR revealed that CCL4, CCR5, and CCL2 mRNA levels were increased in CP patients' gingivae and aortas from coronary artery bypass grafting (CABG) patients. Marked c-Jun, c-Fos, and NF-κB gene productions were detected in CP patients' gingivae but did not show statistical differences between the CAD and non-CAD groups. Stronger immunoreactivity against CCL2 was observed in periodontitis gingiva and aorta from CABG patients. CONCLUSIONS: Our findings suggest that the CCL4/CCR5/c-Jun and c-Fos/CCL2 pathways may be involved in CCL2 expression in periodontitis. CCL4, CCR5, and CCL2 might act as possible nodes to link the presence of periodontitis and atherosclerosis.

Immobilization of poly-L-lysine brush via surface initiated polymerization for the development of long-term antibacterial coating for silicone catheter.

Bacterial colonization of indwelling catheter remains a major threat in healthcare units worldwide. Developing approaches to prevent catheter-associated infections (CAIs) is, therefore, in great demand. Herein, to endow silicone catheter with long-term antibacterial properties, antimicrobial poly-L-lysine (PLL) brush was developed on the surface of catheter via surface initiated ring open polymerization. Surface characterizations confirmed the successful immobilization of PLL. The PLL-tethered catheter showed potent antibacterial activities against catheter-associated urinary tract infections (CAUTIs) related pathogens. Moreover, after immersing in simulated body fluid for 28 days or incubating at 60 °C for 65 days, the bactericidal properties of PLL-tethered catheter were still retained. Furthermore, the PLL-tethered catheter exhibited good anti-infection activity and biocompatibility in vivo. The PLL-tethered surfaces hold great potential in the development of antibacterial silicone catheter to combat CAIs in clinical applications.

High-efficient lignin-based polymerizable macromolecular photoinitiator with UV-blocking property for visible light polymerization.

Developing high-efficient visible light macromolecular photoinitiator (macro PI) with excellent initiation performance, low migration, high biosafety and multi-function is beneficial to broaden the application of photopolymer. Lignin contains chromophores which could generate free radicals under light irradiation. In this study, a lignin-based polymerizable macro PI (DAL-11ene-amine) was designed and synthesized through covalent grafting 10-undecenoyl chloride (11ene) and hydrogen donor 4-(dimethylaminobenzoic acid) ethyl ester (EDAB) into dealkaline lignin (DAL) skeleton. The structure of DAL-11ene-amine was characterized by UV-vis, FTIR, 1H NMR, GPC, and 31P NMR spectra. Under the irradiation of a 405 nm LED, DAL-11ene-amine can directly produce active species and initiate the polymerization of acrylate monomers or thiol-ene click reaction. The photoinitiation efficiency of DAL-11ene-amine is higher than that of DAL-11ene or the two-component combination of DAL-11ene and EDAB. Using DAL-11ene-amine as PI, the prepared polymer films exhibit excellent UV-blocking property. With only 0.5 wt% addition of DAL-11ene-amine, nearly 100% of UVB + UVC and the most of UVA can be blocked by the films. Moreover, DAL-11ene-amine exhibits higher migration stability and biosafety because it can be covalently linked into polymer cross-linking networks. The results indicate that DAL-11ene-amine has great application potentials in preparing environmentally friendly UV-blocking films and biosafety coatings.

Polyethylene glycol-functionalized benzylidene cyclopentanone dyes for two-photon excited photodynamic therapy.

A series of polyethylene glycol-functionalized benzylidene cyclopentanone dyes with varying lipid/water partition coefficients were synthesized in high yields by a simple process. Detailed characterization and systematic studies of these molecules, including linear and nonlinear photophysical properties, reactive oxygen yields, and in vitro photodynamic therapy (PDT) activities, were conducted. Four of these dyes exhibited good solubility in PBS (>2 mg ml(-1), which is sufficient for clinical venous injection), high reactive oxygen yields, large two-photon absorption and low dark toxicity, under the therapy dosage. Among them, two dyes could be absorbed efficiently by human rectal cancer 1116 cells, and presented strong two-photon excited PDT activity in in vitro cell experiments.

Pneumonitis, appendicitis, and biliary obstruction during toripalimab treatment in a patient with extensive-stage small-cell lung cancer: a case report.

In recent years, immune checkpoint inhibitors (ICIs) have become a standard treatment for patients with advanced lung cancers. With the widespread use of immunotherapy in clinical practice, immune-related adverse events (irAEs) have become increasingly common. This case report details a 72-year-old man with small-cell lung cancer (SCLC) who developed pneumonitis, appendicitis, and biliary obstruction during treatment with toripalimab. The patient was initially diagnosed with limited-stage SCLC in January 2019 and completed 5 sequential cycles of etoposide/cisplatin (EP) and radiotherapy (60 Gy/30 F). The overall response was complete response (CR) after first line treatment. He developed radiation pneumonitis after completion of radiotherapy, which responded well to symptomatic treatment. Due to newly diagnosed bone metastasis, he was administered toripalimab intravenously every 3 weeks and 12 mg anlotinib orally once a day from January 2020. By the third cycle, the patient presented with electrocardiographic abnormalities, gingival swelling and pain, and hoarseness, and consequently, the anlotinib was suspended. After 4 cycles, he developed suppurative appendicitis, which was managed successfully with anti-inflammatory agents. He then presented with shortness of breath on exertion and after a comprehensive examination, he was diagnosed with ICI-related-pneumonitis. After 6 weeks of treatment with methylprednisolone, the shortness of breath was mostly relieved and treatment continued. In June 2020, the patient developed severe vomiting. Computed tomography (CT) indicated biliary obstruction, and at endoscopic retrograde cholangiopancreatography (ERCP) there was edema of the major papilla of the duodenum. The patient's symptoms were relieved after treatment with gastric acid suppression and antiemetics. Re-examination by magnetic resonance imaging (MRI) showed that the biliary obstruction had been resolved. Although the disease progressed after immunotherapy, no tumor tissue related to the biliary obstruction was detected, and this was therefore classified as an irAE.

Interlayer expansion of 2D MoS2 nanosheets for highly improved photothermal therapy of tumors in vitro and in vivo.

Interlayer-expanded MoS2 (E-MoS2) nanosheets with an interlayer spacing of 0.94 nm are demonstrated to show an high photothermal conversion efficiency of ∼62%. More importantly, such biocompatible E-MoS2 nanosheets show highly improved photothermal therapy (PTT) of tumors in vitro and in vivo under near-infrared light irradiation.

Water-soluble benzylidene cyclopentanone based photosensitizers for in vitro and in vivo antimicrobial photodynamic therapy.

Antimicrobial photodynamic therapy (aPDT) has been proposed to cope with the increasing antibiotic resistance among pathogens. As versatile pharmacophores, benzylidene cyclopentanone based photosensitizers (PSs) have been used in various bioactive materials. However, their reports as aPDT agents are very limited, and relationships between their chemical structures and antibacterial abilities have not been systematically discussed. Here, nine water-soluble benzylidene cyclopentanone PSs modified by polyethylene glycol (PEG), carboxylate anionic or pyridyl cationic agents are studied for aPDT. It is found that the binding/uptake abilities and aPDT effects of these PSs toward bacterial cells vary significantly when adjusting the number and position of their terminal charged groups. Though the comparable (also best) binding/uptake amounts are achieved by both cationic PS P3 and anionic PS Y1, only Y1 exhibits much more excellent aPDT activities than other PSs. Antibacterial mechanisms reveal that, relative to the favorable cell wall-binding of cationic PS P3, the anionic PS Y1 can accumulate more in the spheroplast/protoplast of methicillin-resistant Staphylococcus aureus (MRSA), which ensures its high efficient aPDT abilities both in vitro and in vivo. This study suggests the great clinical application potential of Y1 in inactivation of MRSA.

Effective Two-Photon Excited Photodynamic Therapy of Xenograft Tumors Sensitized by Water-Soluble Bis(arylidene)cycloalkanone Photosensitizers.

A series of bis(arylidene)cycloalkanone photosensitizers modified by polyethylene glycol (PEG) have been studied for two-photon excited photodynamic therapy (2PE-PDT). As compared with their prototype compounds, these PEGylated photosensitizers show enhanced water solubilities while their photophysical and photochemical properties, including linear absorption, two-photon absorption, fluorescence, and singlet oxygen quantum yield, remain unaltered. In vitro behaviors (cellular uptake, subcellular localization, photocytotoxicity in both PDT and 2PE-PDT) of these photosensitizers reveal that an optimized lipid-water partition coefficient can be obtained by adjusting the length and position of the PEG chains. Among them, the photosensitizer modified asymmetrically by two tetraethylene glycol chains presents the best performance as a 2PE-PDT candidate. Selective blood-vessel closure and obvious therapeutic effect in inhibiting the growth of tumors are confirmed by in vivo 2PE-PDT after intravenous injection of this photosensitiezer. The survival periods of treated tumor-bearing mice are significantly prolonged. This study demonstrates the feasibility of using a simple molecule to construct a potential candidate for 2PE-PDT.