Chemodynamic therapy (CDT) is widely explored for tumor-specific therapy by converting endogenous H 2 O 2 to lethal •OH to destroy cancer cells. However, •OH scavenging by glutathione (GSH) and insufficient intratumoral H 2 O 2 levels seriously hinder the application of CDT. Herein, we reported the fabrication of copper ion-doped ZIF-8 loaded with gold nanozymes and doxorubicin hydrochloride (DOX) for the chemotherapy and CDT synergistic treatment of tumors with the assistance of tumor microenvironment (TME)-activated fluorescence imaging. The Cu 2+ -doped ZIF-8 shell was gradually degraded to release DOX and gold nanoclusters responding to the acidic TME. The fluorescence signal of the tumor region was acquired after the quenched fluorescence of the gold nanoclusters by Cu 2+ and DOX by aggregation-induced quenching was turned on because of the interaction of GSH with Cu 2+ and the release of free DOX. The Cu 2+ ions could deplete the GSH via redox reactions and the generated Cu + could convert internal H 2 O 2 to •OH for tumor CDT. The chemotherapeutic effect of DOX was strengthened through drug efflux inhibition and drug sensitivity increase due to the consumption of GSH and •OH burst. Moreover, DOX could raise the level of H 2 O 2 and augment the effect of CDT. In addition, the fluorescent gold nanoclusters not only served as a peroxidase to convert H 2 O 2 to •OH but also employed as an oxidase to consume GSH, resulting in the amplification of chemotherapy and CDT. This work presents an approach to construct tumor microenvironment-activated theranostic probes without external stimuli and to achieve the tumor elimination through cascade reactions and synergistic treatment.

c Long-term infection with high-risk human papillomavirus (HPV) is the leading cause of cervical cancer, while infection with low-risk HPV is the major reason for condylomata acuminata. An accurate, rapid, and convenient assay that is able to simultaneously detect, genotype, and quantify HPV would be of great clinical value yet remains to be achieved. We developed a three-color real-time PCR assay that is able to analyze 30 predominant HPV types in three reactions. The amplification curves indicated the presence of HPV, melting curve analysis identified the HPV genotype, and the quantification cycle value determined the quantity. We applied this assay to 647 cervical swab samples, and the results were compared with those obtained with a commercial genotyping system. The proposed assay had a limit of detection of 5 to 50 copies per reaction and a dynamic range of 5 ؋ 10 1 to 5 ؋ 10 6 copies per reaction. A comparison study showed that the overall sample concordance with the comparison method was 91.6% and the type agreement was greater than 98.7%. The quantification study demonstrated that the loads of HPV type 16 in 30 samples with cervical intraepithelial neoplasia grade III (CIN III) lesions were significantly higher than those in samples with CIN I lesions or CIN II lesions, and the results were concordant with those of the comparison method. The increased information content, high throughput, and low cost would facilitate the use of this real-time PCR-based assay in a variety of clinical settings.

Polyethylene glycol (PEG) is recognized as an attractive excipient to modify liposomes due to its extended-circulation properties. Nevertheless, intravenous injection of polyethylene glycol-coated liposomes (PEG-L) usually triggers a rapid systemic clearance of the subsequent dose from blood circulation, which is referred to as an accelerated blood clearance (ABC) phenomenon. Therefore, since the induction of cytochrome P450 (P450) activity may lead to enhanced drug clearance, it motivated us to investigate the possibility of P450 involvement in the ABC phenomenon. In this study, polyethylene glycol-coated liposomal docetaxel was prepared and used to evaluate the magnitude of the ABC phenomenon in rats induced by repeated injection of PEG-modified liposomes. Notably, the ABC phenomenon was observed when the time interval between two doses was from 1 to 7 days, and its magnitude reached the maximum level at 3 days before gradually decreasing the time. Meanwhile, increased activity of CYP3A1, CYP2C6, and CYP1A2 was detected when PEG-L was repeatedly injected in male rats at a 3-day interval. Consistently, the expression levels of hepatic CYP3A1, CYP2C6, and CYP1A2 were also significantly increased in the repeated injection groups and their levels were highest in the 3-day interval group. P450 selective inhibitors confirmed the inhibition of hepatic CYP3A1 was accompanied by an attenuated magnitude of the ABC phenomenon, which strongly suggests that P450s may be induced by repeated injection of PEG-L, thus favoring metabolic clearance of the second dose. Collectively, herein, for the first time we demonstrate that the contribution of P450s should not be ignored in the ABC phenomenon.

No abstract

Recent viral metagenomic studies have demonstrated the diversity of eukaryotic viruses and bacteriophage shed in the feces of domestic species. Although enteric disease is a major concern in the commercial mink farming industry, few etiologic agents have been well characterized. This study aimed to identify viruses shed in the fecal matter of clinically healthy commercial mink from 40 southern Ontario farms. Viral RNA was extracted from 67 pooled fecal samples (30 adult female mink and 37 kit) and amplified for Illumina sequencing on the NextSeq platform, and the resulting contigs were trimmed and assembled using Trimmomatic 0.36.0 and Spades 3.8.0 in iVirus (CyVerse, AZ, USA) and SeqMan NGen 12 (DNAStar, WI, USA). Identification of assembled sequences >100 bp (Geneious 10.1.3) showed an abundance of bacteriophage sequences, mainly from families Siphoviridae (53%), Podoviridae (22%), Myoviridae (20%), Inoviridae (1%), Leviviridae (0.04%), Tectiviridae (0.01%), and Microviridae (0.01%). A diverse range of vertebrate viruses were detected, of which posavirus 3, mink bocavirus, gyroviruses, and avian-associated viruses were most abundant. Additionally, sequences from nonvertebrate viruses with water and soil-associated amebal and algal hosts were also highly prevalent. The results of this study show that viruses shed in the fecal matter of healthy commercial mink are highly diverse and could be closely associated with diet, and that more research is necessary to determine how the detected viruses may impact mink health.

No abstract

The genotype of the hepatitis C virus (HCV) is an important indicator for antiviral therapeutic response. We hereby described development of a rapid HCV genotyping approach that enabled the identification of the six most common HCV subtypes of Asia, i.e., 1a, 1b, 2a, 3a, 3b, and 6a, in a single reaction. Using two dual-labeled, self-quenched probes that target the core region of the HCV genome, the exact subtype could be accurately identified by two-melting temperature codes determined from the two respective probes in a real-time PCR assay. Analytical sensitivity studies using armored RNA samples representing each of the six HCV subtypes showed that 5 copies/reaction of HCV RNA could be detected. The assay was evaluated using 244 HCV-positive serum samples and the results were compared with sequencing analysis. Of the 224 samples, subtype 3a (127, 52.3%) was the dominant, followed by 1b (51, 20.9%), 3b (47, 19.3%), 2a (8, 3.3%), 6a (4, 1.6%) and the least was subtype 1a (1, 0.4%). Moreover, 6 (2.5%) mixed infection samples were also detected. These results were fully concordant with sequencing analysis. We concluded that this real-time PCR-based assay could provide a rapid and reliable tool for routine HCV genotyping in most Asian countries.

No abstract