The prognostic role of radiotherapy and radiotherapy target in cervical lymph node metastatic squamous cell carcinoma with unknown primary: a retrospective study.

OBJECTIVES: Aim to analyze the effect of radiotherapy for cervical lymph node metastatic carcinoma with unknown primary (CCUP) and compare the survival benefits between Comprehensive radiotherapy and Involved Field radiotherapy. MATERIALS AND METHODS: The patients diagnosed with CCUP between 2009 and 2019 in our institution were analyzed retrospectively. The categorical variables were tested by χ2 test. Kaplan-Meier method was used for survival analysis. Log-rank test and Cox proportional hazards regression were performed with overall survival (OS) and disease-free survival (DFS) as the primary outcome variables. RESULTS: Of 139 patients, 64.7% (90/139) of them received radiotherapy. Of the 90 patients who underwent radiotherapy, 45.6% (41/90) received Involved Field radiotherapy and the rest 49 patients received Comprehensive radiotherapy. The median follow-up of 139 patients is 69 months. The 1-year, 3-year, and 5-year OS rates are 87%, 62%, and 39%, respectively, and the DFS rates are 73%, 45%, and 29%, respectively. Multivariate analysis of 139 patients with CCUP shows that differentiation grade, N stage, radiotherapy, and the length of the largest lymph node (DmaxLN) are the independent prognostic factors for both OS and DFS. Subgroup analysis of 90 patients who received radiotherapy shows that the Comprehensive radiotherapy group has a better OS (P < 0.001) and DFS (P < 0.001) compared with Involved Field radiotherapy. CONCLUSION: Radiotherapy is the independent prognostic factor for CCUP. Comprehensive radiotherapy may be superior to Involved Field radiotherapy in survival benefits.

Engineered red blood cell membrane for sensitive and precise electrochemical detection of salivary exosomes.

As a kind of promising non-invasive biomarker, exosomes naturally occurring in saliva have recently attracted considerable attention in view of their potential use in the diagnosis of oral diseases. Herein, we propose a new electrochemical method for the sensitive and precise detection of salivary exosomes. A red blood cell membrane (RBCM) engineered with CD63 aptamer is the core element of the method and is used to camouflage a gold electrode, thus giving the electrode superior antifouling and targeting ability. Target exosomes presented in saliva are recognized and captured by the highly specific interaction between the exosomal CD63 and the aptamers engineered in RBCM. Then, silver nanoparticles modified with CD63 aptamers are recruited onto the electrode surface to generate significant electrochemical signals, which enables the sensitive detection of target exosomes. By using human oral squamous cell carcinoma CAL27 cell-derived exosomes as a model, the method allows target salivary exosome detection in a wide linear range from 5 × 102 to 1 × 106 particles per mL and a low detection limit of 2.07 × 102 particles per mL. Moreover, the method displays good reproducibility and is feasible for detecting target exosomes with high precision in saliva samples. Overall, the method may provide a useful tool for salivary exosome detection and may have great potential for practical use in the clinical diagnosis of oral diseases.

Encapsulation of green tea polyphenol nanospheres in PVA/alginate hydrogel for promoting wound healing of diabetic rats by regulating PI3K/AKT pathway.

Difficult healing of skin wounds is one of the serious complications of diabetes mellitus. Green tea polyphenols (TP) have been found to have good therapeutic effects on wounds healing. However, TP that is soluble in water and easily been oxidized requires a gel material that provides moisture retention, oxidation prevention, and sustained release of TP to achieve better wound healing effect. Therefore, in this work, novel tea polyphenol nanospheres (TPN) were synthesized and encapsulated in a PVA /alginate hydrogel (TPN@H). The prepared TPN@H was characterized and applicated in model diabetic rats for promoting wound healing and regulating immune response. Fourier-transform infrared spectroscopy (FT-IR), UV spectroscopy, scanning electron microscopy (SEM), atomic force microscope (AFM), confocal laser scanning microscopy (CLSM), dynamic light scattering (DLS) and differential scanning calorimetry (DSC) were used for characterization. Animal experiments and molecular mechanism research proved that TPN@H could promote wound healing of diabetic rats by regulating PI3K/AKT signaling pathway.

pH and folic acid dual responsive polysaccharide nanospheres used for nuclear targeted cancer chemotherapy.

Ideal nanoscale drug delivery system (DDS) should be biocompatible, having targeted recognition and controlled release properties. In this work, monodispersed, doxorubicin (Dox) loaded chitosan (Cts) nanospheres functionalized by mesoporous SiO2 and folic acid (FA) were prepared, briefly named as DCSF NSs. The prepared raspberry-like DCSF NSs had an average size of 440 nm and drug loading efficiency (DLE) of 42.61%. The drug release results confirmed that the release of Dox could be controlled by pH change. Cell apoptosis results indicated that the obtained DCSF NSs could kill 90% of MCF-7 cells in 48 h. Confocal laser scanning microscopy (CLSM) results further revealed that folic acid could mediate the cellular uptake of DCSF NSs. These results demonstrated that the obtained DCSF NSs were pH-responsive, folic acid-triggered nuclear targeted, which can be used as ideal DDS for tumor chemotherapy.

8DSS peptide induced effective dentinal tubule occlusion in vitro.

OBJECTIVE: Eight repetitive nucleotide sequences of aspartate-serine-serine (8DSS) derived from dentin phosphoprotein (DPP) has been proved to be a good remineralization agency. In this study, 8DSS peptide was employed to induce dentinal tubule occlusion. METHODS: Dentin samples were acid-etched, and then the samples were coated with 8DSS solution. The binding capacity of 8DSS to acid-etched dentin was tested by attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR). Subsequently, the 8DSS-treated dentin samples were immersed in artificial saliva for 1, 2 and 4 weeks. After 4 weeks, the remineralized dentin was treated with 6wt% citric acid (pH 1.5) solution for 1min. Dentin permeability measurement and scanning electron microscopy (SEM) were carried out after different periods. Energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) were used to identify the mineral phase of the regenerated minerals. RESULTS: The results showed that 8DSS had a good binding capacity to the acid-etched dentin, and significantly reduced the dentin permeability by inducing minerals deposited within the dentinal tubules. After 4 weeks, all the dentinal tubules were occluded by large bulk of regenerated minerals, which largely decreased the diameters of the tubules. The regenerated minerals deposited with a deep depth within the dentinal tubules, ensuring an effective occlusion even after an acid challenge. The results of XRD and EDS confirmed that the regenerated minerals were mainly hydroxyapatite (HA). SIGNIFICANCE: 8DSS peptide induced strong dentinal tubule occlusion. 8DSS have a great potential to be used in the treatment of dentin hypersensitivity in the future.

Bioinspired Peptide-Decorated Tannic Acid for in Situ Remineralization of Tooth Enamel: In Vitro and in Vivo Evaluation.

Tooth enamel can be eroded by the local cariogenic bacteria in plaque or nonbacterial factors in the oral environment. The damage is irreversible in most situations. For the etched human tooth enamel to be restored in situ, a salivary-acquired pellicle (SAP) bioinspired tannic acid (SAP-TA) is synthesized. Statherin is one of the SAP proteins that can selectively adsorb onto enamel surface. Peptide sequence DDDEEKC is a bioinspired sequence of statherin and has the adsorption capacity of hydroxyapatite (HAP). TA has abundant polyphenol groups that can grasp Ca2+ in saliva to induce the regeneration of HAP crystal. Hence, SAP-TA not only enhances the binding force at the interface of remineralization but also mimics the biomineralization process of tooth enamel. Moreover, ferric ion can coordinate with SAP-TA to form a compact coating that increases the adsorbed amounts of SAP-TA on tooth enamel. Compared with SAP-TA alone, the etched enamels treated with SAP-TA/Fe(III) have a better remineralization effect and mechanical properties (surface microhardness recovery >80% and binding force of 64.85 N) when being incubated in artificial saliva for 2 weeks. In vivo remineralization performance is evaluated in a classical rat caries model. The polarizing microscope and micro-CT results show that SAP-TA/Fe(III) has a good effect on the remineralization process in a real oral environment, indicating that it is a promising repair material for in situ remineralization of enamel.

Natural products and caries prevention.

Dental caries is considered as the most common polymicrobial oral disease in the world. With the aim of developing alternative approaches to reduce or prevent the decay, numerous papers showed the potential anticaries activity of a number of natural products. The natural products with anticaries effects are selected from e.g. food, beverages, flowers or traditional herbs. Most of the effective components are proven to be polyphenol compounds. Many of the natural products are studied as antibacterial agents, while some of them are found to be effective in shifting the de-/remineralization balance. However, the mechanisms of the anticaries effects are still unclear for most of the natural products. In the future, more efforts need to be made to seek novel effective natural products via in vitro experiment, animal study and in situ investigations, as well as to enhance their anticaries effects with the help of novel technology like nanotechnology.

Effective dentin restorative material based on phosphate-terminated dendrimer as artificial protein.

In clinic, it calls for effective and simple materials to repair etched dentin. Bioinspired by the natural mineralization process guided by noncollagenous proteins (NCPs), in this work, we synthesized the fourth generation phosphate-terminated polyamidoamine dendrimer (G4-PO3H2) by one-step modification. We used FT-IR and 1H NMR to characterize the structure of G4-PO3H2, and MTT assay to prove its biocompatibility. It was applied as the analog of dentin phosphophoryn (DPP: a type of NCPs) to repair dentin, due to its similar dimensional scale, topological architecture and peripheral functionalities to that of DPP. By the characterization of SEM and XRD, the effective regeneration of human dentin induced by G4-PO3H2 is characterized and illustrated both in vitro (artificial saliva) and in vivo (oral cavity of rats). It is noted that the thickness of the regenerated mineral layers are more than 10 µm both in vitro and in vivo. The design strategy of G4-PO3H2 may be valuable for researchers in the fields of material science, stomatology and medicine to prepare various promising restorative nano-materials for biomineralized hard tissues such as bone and teeth.

Novel tea polyphenol-modified calcium phosphate nanoparticle and its remineralization potential.

Tea polyphenols (TP) are not only potent antimicrobial and antioxidant agents but also effective modifiers in the formation of nanosized crystals. Since nano-hydroxyapatite (n-HA) is known to enhance remineralization of dental hard tissue, our aims were to synthesize nanosized calcium phosphate particles incorporating TP and to test their potential as caries preventive agent. An ammonia water diffusion method was used to synthesize nanosized calcium phosphate particles (TP-CaP) in the presence of various amounts of TP. The resultant products were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The remineralization potential of the nano TP-CaP was then investigated in a 12-day pH-cycling model. Nano TP-CaP slurries, at pH 7.0 and pH 5.5, were applied onto preformed enamel lesions 4 × 3 min per day. n-HA slurries at pH 7.0 and pH 5.5 were used as positive controls, and deionized water was served as a negative control. SEM showed nanosized particles were only formed at 27 mg/mL of TP. Further characterization of the nanosized particles revealed the components were amorphous calcium phosphate, HA, and TP. Both surface microhardness and transverse microradiography analyses showed that nano TP-CaP at pH 5.5, but not at pH 7.0, significantly enhanced remineralization, to the same extent as the n-HA controls. Furthermore, significantly higher amount of TP was found in the supernatant of TP-CaP at pH 5.5 than those at pH 7.0. Since TP can inhibit bacterial growth and enzyme activities, the novel nanosized TP-CaP particle, at low pH, is a potential dual-functional-remineralization and antibacteria-product.

The effects of light on bleaching and tooth sensitivity during in-office vital bleaching: a systematic review and meta-analysis.

OBJECTIVE: To evaluate the influence of light on bleaching efficacy and tooth sensitivity during in-office vital bleaching. DATA SOURCES: We performed a literature search using Medline, EMBASE and Cochrane Central up to September 2011. STUDY SELECTION: All randomised controlled trials (RCTs) or quasi-RCTs comparing the light-activated bleaching system with non-activation bleaching system were included. Reports without clinical data concerning bleaching efficacy or tooth sensitivity were excluded. RESULTS: Eleven studies were included in the meta-analysis. A light-activated system produced better immediate bleaching effects than a non-light system when lower concentrations of hydrogen peroxide (15-20% HP) were used (mean difference [MD], -1.78; 95% confidence interval [CI]: [-2.30, -1.26]; P<0.00001). When high concentrations of HP (25-35%) were employed, there was no difference in the immediate bleaching effect (MD, -0.39; 95% CI: [-1.15, 0.37]; P=0.32) or short-term bleaching effect (MD, 0.25; 95% CI: [-0.47, 0.96]; P=0.50) between the light-activated system and the non-light system. However, the light-activated system produced a higher percentage of tooth sensitivity (odds ratio [OR], 3.53; 95% CI: [1.37, 9.10]; P=0.009) than the non-light system during in-office bleaching. CONCLUSIONS: Light increases the risk of tooth sensitivity during in-office bleaching, and light may not improve the bleaching effect when high concentrations of HP (25-35%) are employed. Therefore, dentists should use the light-activated system with great caution or avoid its use altogether. Further rigorous studies are, however, needed to explore the advantages of this light-activated system when lower concentrations of HP (15-20%) are used.