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The development of a rapid and sensitive detection platform for DNA and DNA methylation in complex biological environments has attracted considerable attention. Herein, we describe a detection platform for p16 and p16 methylation in buffer and serum based on a single polymeric fluorescent microfiber waveguide with sandwich-structured hybridization designs. The target p16 could be captured by oligonucleotides conjugated on the surface of polymeric microfibers and oligonucleotides conjugated with gold nanoparticles, resulting in quenching the out-coupled tip emission of the microfiber waveguide. Then the restriction digestion enzyme HpaII was applied to specifically recognize the unmethylated 5'-CCGG-3' site and cut the formed sandwich structure. The gold nanoparticles could be removed from the surface of chitosan fiber so that the out-coupled tip emission of the polymeric fluorescent microfiber would be partially recovered. It is noteworthy that the proposed polymeric microfiber waveguide platform exhibited selective and sensitive detection of p16 with a low limit of 2 pM and excellent analytical performance of methylation as low as 5% difference. This strategy avoids the use of traditional PCR-based amplification and tedious operative processes, and we envisage that this technique could be extended to various DNA methylation analyses, which is meaningful for early clinical diagnosis of diseases.

Accurate, robust, and rapid diagnostics is the basis for all well-functioning healthcare. There is a large need in point-of-care biosensors to facilitate diagnosis and reduce the need for cumbersome laboratory equipment. Proteases are key virulence factors in periodontitis. Periodontal disease is very common and characterized by inflammation and infection in the tooth-supporting structures and is linked to many systemic diseases such as cardiovascular disease, diabetes, and Alzheimers disease. Proteases present in periodontal disease, gingipains, are highly responsible for the disease onset and progression and are therefore a promising biomarker. Here we show a novel nanopore-based biosensor strategy for protease activity monitoring. Solid-state nanopores were modified with a proteolytic substrate, restricting the ionic current through the apertures of the nanopores. Protease can digest the proteolytic substrate thus enlarge the aperture and the ionic current. Trypsin was used as an initial model protease to investigate the performance of the sensor. We show that the solid-state nanoporebiosensor can detect trypsin with a limit of detection (LOD) of 0.005 ng/mL (0.2 pM). The detection system developed for the model enzyme was then applied to the detection of gingipains. The LOD for detection of gingipains was 1 ng/mL (0.02 nM), with a 27% recovery of the signal at 0.1 mu g/mL, indicating that the sensitivity and dynamic range are relevant for the clinical diagnosis of periodontitis. The generic detection of protease activity and high sensitivity make this a promising sensor technology for both diagnosis of periodontal disease and monitoring of other disease-related proteases. Funding Agencies|Swedish Strategic Research Foun-dation [SSF FFL15-0174, FFL15-0026]; Swedish Research Council [VR 2019-04690, VR 2017-04475, VR 2016-04874]; Swedish Cancer Foundation [CAN 2017/430]; Wallenberg Academy Fellow Program [KAW 2020.0190, KAW 2016.0231]

Catalytic hairpin assembly (CHA) is a typical enzyme-free amplification strategy, in which the target can catalyze two hairpin probes to form a duplex and yield multiple outputs signal. However, the non-specific hybridization of two hairpin probes in CHA circuit usually occurred even in the absence of target, causing significant background leakage and impeding its practical applications in trace miRNA analysis. Herein, we proposed a novel heterogeneous CHA (hetero-CHA) design integrating with PDA microtube waveguide system, offering the advantages to enhance the target signal, but suppress the background leakage simultaneously. In hetero-CHA strategy, single-stranded targets are enriched nearby the surface of PDA microtube, facilitating the target-triggered CHA amplification and strand displacement reactions. In contrast, double-stranded DNA complexes formed by uncatalyzed hybridizations are isolated from PDA microtube, impeding the leakage signal. By combination with condensing enrichment effect, the proposed hetero-CHA probe exhibited high selectivity and sensitivity to miRNA target, giving a detection limit as low as 3.3 fM. More importantly, the proposed hetero-CHA probe can be applied directly to distinguish the expression of miRNA-21 in clinical serum of cancer patients (including lung, breast and pancreatic) from those of healthy human beings, favoring the cancer diagnosis and therapeutic evaluation.

Here, we present a novel PDA microtube waveguide platform by combining heterogeneous CHA amplification with competitive inhibition. The heterogeneous CHA amplification system can preferentially amplify the signal of the correct target, while the competitive inhibition system will preferentially bind with the mutant targets and inactivate their signal.

Herein, we study the enantioselective cytotoxicity of vesicles self-assembled by optically active linear polymers (LNPs) and hyperbranched polymers (HBPs). Compared to HBP vesicles, LNP vesicles exhibit properties such as a higher surface charge density and more violent interaction with simulated biomembranes which results in larger cytotoxicity against HeLa cells. Specifically, racemic-LNP vesicles exhibit the largest cytotoxicity of all. More interestingly, there is no significant enantioselective dependence of HBP vesicles on the abovementioned properties. Overall, we proved that the cytotoxicity of vesicles is deeply related to chirality and topological-structures. This research is of great fundamental value for the design of novel bio-interface materials.

THOR, a highly conserved lncRNA, is potentially involved in various cancer development. However, its involvement in tongue squamous cell carcinoma (TSCC) remains unclear. The present study aims to explore the biological function and molecular mechanism of THOR in TSCC progression. The expressions of THOR and IGF2BP1 in TSCC tissues and adjacent non-cancerous tongue tissues (ANT) were examined through qRT-PCR. THOR levels were manipulated in TSCC cells to explore its function in cancer progression in vitro and in vivo, which were subsequently evaluated by CCK8, colony formation assay, flow cytometry, xenograft tumor assays. In situ hybridization, RIP and Western blot assay were performed to explore the underlying molecular mechanisms. We discovered that THOR and IGF2BP1 were dramatically upregulated in TSCC tissues. The expression of THOR is positively correlated with IGF2BP1 mRNA level. THOR mediated IGF2 expression via interacting with IGF2BP1, and affected the downstream MEK-ERK signaling pathway to regulate TSCC cells proliferation. THOR/IGF2BP1/IGF2-MEK-ERK axis regulated the proliferation of TSCC cells, implying that THOR would be a promising therapeutic target for TSCC patients.

MicroRNAs (miRNAs) have emerged as novel biomarkers for human early-phase cancer diagnosis and disease prevention recently. Herein, we reported a novel miRNA-215 targeting biosensor, which was based on single polydiacetylene (PDA) microtube waveguide system integrated with sandwich-type hybridization design and condensing enrichment effect. The target miRNA could be captured by oligonucleotides conjugated on the surface of PDA microtube and Au nanorod (AuNR) respectively, resulting in the out-coupled fluorescence of PDA microtube quenching. In this strategy, the formation of a sandwich structure, as a result of co-hybridization of the target miRNA, enabled simplified preparation process, enhanced reaction efficiency, and increased recyclability and stability of the platform. Based on condensing enrichment effect, the co-hybridization reaction could be enriched on the surface of microtube and the proposed platform could easily achieve highly sensitive detection of miRNA-215 in one step. Remarkably, this platform could be directly applied to discriminate the miRNA-215 expression levels in clinical gastric cancerous, paracancerous and normal tissues samples. This assay offers a simple and convenient method for miRNA quantification in clinical samples, even with the potential for invasive, portable equipment for early clinical diagnosis of diseases.

The aim of the study was to find out what perioperative risk factors predicted complications in patients having reconstructions with radial forearm free flaps (RFFF). We organised a retrospective study of 169 patients (mean (range) age 54 (22-86) years, 100 of whom were female) who had oral and maxillofacial tumours resected, and reconstructed with RFFF, from January 2011-December 2016. We recorded predictive variables, subdivided into: personal and clinical (sex, age, weight, coexisting conditions, history of smoking, radiotherapy, and primary lesions); haemodynamic (perioperative concentrations of haemoglobin and albumin, blood loss, blood transfusion, urinary output (ml), and rate (ml/kg/hour), and infusion rates for crystalloids and colloids (ml/kg/hour, and volumes given intraoperatively and postoperatively for 24hours); and anaesthetic and surgical (American Society of Anesthesiologists(ASA) grade, visual analogue pain score (VAS), and duration of tourniquet and operation). The primary outcome was the presence of a postoperative complication, and the secondary outcome the types of complications (medical and surgical). The significance of differences among the variables was assessed by univariate and multivariate analysis, and probabilities of less than 0.05 were accepted as significant. There were 26 complications, of which 15 were surgical and 11 medical. Risk factors were: preoperative radiotherapy, postoperative haemoglobin and albumin concentrations, VAS for pain, and volume of crystalloids transfused during the first 24hours. Although reconstruction with a RFFF is a common and safe treatment for patients with oral and maxillofacial tumours, regulating perioperative risk factors, particularly those related to anaesthesia (including VAS and management of fluids) is important in the reduction of the number of complications.

Purpose Fibular free flap transfer is a powerful tool available to the reconstructive surgeon when treating oral and maxillofacial defects, but complications still occasionally occur and predictive analysis focusing on this specific flap is limited in terms of risk factors for complication. The purpose of this study was to identify key variables associated with complications in patients undergoing fibular free flap transfer. Patients and Methods The data of 163 consecutive patients who underwent fibular free flap surgery at the Department of Oral and Maxillofacial Surgery, Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University, between 2012 and 2015 were reviewed retrospectively. Patient demographic data, laboratory data, surgical data, and fluid infusion–related data that may have an influence on free flap outcomes were recorded. Univariate and multivariate logistic regression analyses were used to identify relevant risk factors. Results A total of 163 fibular free flaps were transferred for mandibulofacial reconstruction in 163 patients with a mean age of 50.9 years. Postoperative complications developed in 33 (20.2%). Multivariate analysis showed that free flap complications were significantly associated with radiotherapy history (odds ratio [OR], 5.12; P = .001), postoperative anemia (OR, 1.048; P = .041), postoperative hypoalbuminemia (OR, 0.844; P = .002), and prolonged operative time (OR, 1.005; P = .004). Conclusions Radiotherapy history, decreased postoperative hemoglobin and albumin levels, and prolonged operative time are potential predictors of postoperative complications after fibular free flap reconstruction for mandibulofacial defects.

Opioids have been widely used in clinical practice as potent pain relievers for centuries. However, opioids have many deleterious effects. It has been reported that opioid increases tau protein phosphorylation. Hyperphosphorylation of tau is also a pathological feature of Alzheimer's disease and other chronic neurodegenerative disorders. However, the underlying mechanism by which opioids enhance tau phosphorylation is not yet known. In this study, we treated rat embryo cortical neurons with morphine and observed its effect on tau phosphorylation. We found that morphine induced tau hyperphosphorylation and increased levels of phospho-JNK and phospho-p38; these effects were blocked by pretreatment with naloxone. Inhibition of JNK by SP600125 significantly reduced tau hyperphosphorylation in neurons treated with morphine. Similarly, SB203580, an antagonist of p38 MAPK, abolished tau hyperphosphorylation in neurons treated with morphine. Our data suggest that JNK/p38 MAPK, activated by morphine in an opioid receptor-dependent manner, may lead to tau hyperphosphorylation.