Prediction of Bone Healing around Dental Implants in Various Boundary Conditions by Deep Learning Network.

Tissue differentiation varies based on patients' conditions, such as occlusal force and bone properties. Thus, the design of the implants needs to take these conditions into account to improve osseointegration. However, the efficiency of the design procedure is typically not satisfactory and needs to be significantly improved. Thus, a deep learning network (DLN) is proposed in this study. A data-driven DLN consisting of U-net, ANN, and random forest models was implemented. It serves as a surrogate for finite element analysis and the mechano-regulation algorithm. The datasets include the history of tissue differentiation throughout 35 days with various levels of occlusal force and bone properties. The accuracy of day-by-day tissue differentiation prediction in the testing dataset was 82%, and the AUC value of the five tissue phenotypes (fibrous tissue, cartilage, immature bone, mature bone, and resorption) was above 0.86, showing a high prediction accuracy. The proposed DLN model showed the robustness for surrogating the complex, time-dependent calculations. The results can serve as a design guideline for dental implants.

A microwell array structured surface plasmon resonance imaging gold chip for high-performance label-free immunoassay.

Surface plasmon resonance imaging (SPRi) offers a compelling method for high-throughput, real-time, and label-free biomolecular interaction studies and immunoassays, but its performance suffers from limited intrinsic sensitivity and low-contrast SPRi images. Herein we report a high-performance SPRi chip featuring patterned microwell array constructed by photolithography of adhesive polydopamine (PDA) thin film on conventional gold chip. The chip allows for the facile construction of region-defined sensing array on its surface with improved intrinsic SPRi sensitivity due to the intensified surface plasmon wave (SPW) in the microwells. The immunoassay performance of the as-designed SPRi chip is evaluated by using anti-ochratoxin A (anti-OTA) monoclonal antibody as a model target. The results show that this microwell array structured gold chip exhibits ca. 18%-32% higher signal intensity than the conventional gold chip when detecting anti-OTA at different concentrations, and the noise remains at the same level, showing enhanced intrinsic sensitivity. Meanwhile, this microwell-structured chip affords clear and high-contrast SPRi images with well-defined sensing areas, which greatly facilitates the extraction and quantitative analysis of detection signals while efficiently suppressing the disturbance from background areas.

Semiconducting Polymer Nanocavities: Porogenic Synthesis, Tunable Host-Guest Interactions, and Enhanced Drug/siRNA Delivery.

Nanocavities composed of lipids and block polymers have demonstrated great potential in biomedical applications such as sensors, nanoreactors, and delivery vectors. However, it remains a great challenge to produce nanocavities from fluorescent semiconducting polymers owing to their hydrophobic rigid polymer backbones. Here, we describe a facile, yet general strategy that combines photocrosslinking with nanophase separation to fabricate multicolor, water-dispersible semiconducting polymer nanocavities (PNCs). A photocrosslinkable semiconducting polymer is blended with a porogen such as degradable macromolecule to form compact polymer dots (Pdots). After crosslinking the polymer and removing the porogen, this approach yields semiconducting polymer nanospheres with open cavities that are tunable in diameter. Both small molecules and macromolecules can be loaded in the nanocavities, where molecular size can be differentiated by the efficiency of the energy transfer from host polymer to guest molecules. An anticancer drug doxorubicin (Dox) is loaded into the nanocavities and the intracellular release is monitored in real time by the fluorescence signal. Finally, the efficient delivery of small interfering RNA (siRNA) to silence gene expression without affecting cell viability is demonstrated. The combined features of bright fluorescence, tunable cavity, and efficient drug/siRNA delivery makes these nanostructures promising for biomedical imaging and drug delivery.

Mitigation of the corrosion-causing Desulfovibrio desulfuricans biofilm using an organic silicon quaternary ammonium salt in alkaline media simulated concrete pore solutions.

Organic silicon quaternary ammonium salt (OSA), an environmentally friendly naturally occurring chemical, was used as a bacteriostatic agent against sulphate-reducing bacteria (SRB) on a 20SiMn steel surface in simulated concrete pore solutions (SCP). Four different media were used: No SRB (NSRB), No SRB and OSA (NSRB + OSA), With SRB (WSRB), With SRB and OSA (WSRB + OSA). After biofilm growth for 28 days, optimized sessile SRB cells survived at the high pH of 11.35 and as a result these cells caused the breakdown of the passive film due to the metabolic activities of the SRB. Corrosion prevention results showed that the OSA was effective in mitigating the growth of the sessile SRB cells and reduced corrosion in the SCP. These results were further confirmed by scanning electron microscope images, energy dispersive X-ray analysis, confocal-laser scanning microscopy, X-ray photoelectron spectroscopy and corrosion testing using electrochemical analysis.

Combination Cyclophosphamide/Glucocorticoids Provide Better Tolerability and Outcomes versus Glucocorticoids Alone in Patients with Sjogren's Associated Chronic Interstitial Nephritis.

BACKGROUND: Steroid therapy has become an effective option for patients with primary Sjogren's syndrome with tubulointerstitial nephritis (TIN), while the use of cytotoxic agents is still debated. Our study aimed to compare the clinical outcomes of patients treated with cyclophosphamide (CTX) combined with glucocorticoids with those of patients treated with glucocorticoids alone. METHODS: All patients with primary Sjogren's syndrome with chronic TIN admitted to the Division of Nephrology, Ruijin Hospital, from January 1, 2002, to April 30, 2016, and treated with steroids alone or combined with CTX were included. The immunological prognosis, improvements of renal function, and acquired tubular defects of the patients were retrospectively compared between the 2 therapeutic groups. RESULTS: A total of 70 cases were included. Of these, 36 were diagnosed by renal biopsy. A total of 56 patients were treated with glucocorticoids alone, while 14 patients received glucocorticoids combined with CTX. There were no significant differences in clinical characteristics and laboratory parameters between the 2 therapeutic groups at baseline. Compared with patients in the steroid group, patients in the CTX group showed better estimated glomerular filtration rate (eGFR) improvement (21.35 ± 19.63 vs. 2.72 ± 19.11 mL/min/1.73 m2, p = 0.006) but a similar decline in immunoglobulin G (IgG; 450 [interquartile range, IQR 910] vs.176 [IQR 1,910] mg/dL, p = 0.93) at 12 months of follow-up. CTX therapy was associated with better eGFR improvement (ß = 12.96 [2.95-22.97]) even after adjusting for dry mouth, anti-Sjögren's-syndrome-related antigen A and anti-Sjögren's-syndrome-related antigen B positivity, hemoglobin, initial steroid dose, and baseline eGFR by linear regression analyses. Subgroup analyses revealed that the beneficial effects of CTX therapy on renal function were only observed in patients with baseline IgG ≥1,560 mg/dL or eGFR <90 mL/min/1.73 m2. The urine α1-microglobulin improvement was better in the CTX group than in the steroid group at 12 months of follow-up (ß = 1.29, 95% CI 0.56-2.02, p = 0.001). CONCLUSIONS: CTX therapy is suggested for primary Sjogren's syndrome patients with chronic TIN, especially those with higher IgG levels and abnormal renal function at baseline.

iCVD Cyclic Polysiloxane and Polysilazane as Nanoscale Thin-Film Electrolyte: Synthesis and Properties.

A group of crosslinked cyclic siloxane (Si-O) and silazane (Si-N) polymers are synthesized via solvent-free initiated chemical vapor deposition (iCVD). Notably, this is the first report of cyclic polysilazanes synthesized via the gas-phase iCVD method. The deposited nanoscale thin films are thermally stable and chemically inert. By iCVD, they can uniformly and conformally cover nonplanar surfaces having complex geometry. Although polysiloxanes are traditionally utilized as dielectric materials and insulators, our research shows these cyclic organosilicon polymers can conduct lithium ions (Li(+) ) at room temperature. The conformal coating and the room temperature ionic conductivity make these cyclic organosilicon polymers attractive for use as thin-film electrolytes in solid-state batteries. Also, their synthesis process and properties have been systemically studied and discussed.

Environmentally responsive graphene systems.

Graphene materials have been attracting significant research interest in the past few years, with the recent focuses on graphene-based electronic devices and smart stimulus-responsive systems that have a certain degree of automatism. Owing to its huge specific surface area, large room-temperature electron mobility, excellent mechanical flexibility, exceptionally high thermal conductivity and environmental stability, graphene is identified as a beneficial additive or an effective responding component by itself to improve the conductivity, flexibility, mechanical strength and/or the overall responsive performance of smart systems. In this review article, we aim to present the recent advances in graphene systems that are of spontaneous responses to external stimulations, such as environmental variation in pH, temperature, electric current, light, moisture and even gas ambient. These smart stimulus-responsive graphene systems are believed to have great theoretical and practical interests to a wide range of device applications including actuators, switches, robots, sensors, drug/gene deliveries, etc.

Engineering Female Germline Stem Cells with Exocytotic Polymer Dots.

Germline stem cells (GSCs) are the only cell population capable of passing genetic information to offspring, making them attractive targets in reproductive biology and fertility research. However, it is generally more difficult to introduce exogenous biomolecules into GSCs than other cell types, impeding the exploration and manipulation of these cells for biomedical purposes. Herein, semiconductor polymer dots (Pdots)-based nanocomplex Pdot-siRNA is developed and achieves effective knockdown of target genes in female germline stem cells (FGSCs). Advantage of high fluorescence brightness of Pdots is taken for comprehensive investigation of their cellular uptake, intracellular trafficking, and exocytosis in FGSCs. Importantly, Pdots show excellent biocompatibility and minimally disturb the differentiation of FGSCs. Intracellular Pdots escape from the lysosomes and undergo active exocytosis, which makes them ideal nanocarriers for bioactive cargos. Moreover, Pdot-siRNA can penetrate into 3D ovarian organoids derived from FGSCs and down-regulate the expression levels of target genes. This study investigates the interface between a type of theranostic nanoparticles and FGSCs for the first time and sheds light on the manipulation and medical application of FGSCs.

Ion-specific self-assembly of low-dimension aggregate structures of conjugated polymer at two-phase interface.

A novel and facile approach to manipulate the morphology of Cu(2+)-ion-specific assembly of conjugated polymer by coordinative interaction at an oil-water two-phase interface is present. The application of increasing importance is the use of π-conjugated polymers as receptors, exploiting their ability to selectively form complexes, which can obviously change the optical properties in solution and induce the formation of varied solid nano/microstructures. By this method, microtubes are formed through self-rolling of a strained ionic bilayer film at the oil/water interface.

[The efficacy and safety of continuous erythropoietin receptor activator in dialytic patients with chronic renal anemia: an open, randomized, controlled, multi-center trial].

OBJECTIVE: To evaluate the efficacy and safety of continuous erythropoietin receptor activator (C.E.R.A.) once every 4 weeks by subcutaneous administration on hemoglobin (Hb) maintenance in dialytic patients with chronic renal anemia who had been treated with stable dose of erythropoietin (EPO). METHODS: This was an open, randomized, controlled, multi-center trial. All the hemodialysis or peritoneal dialytic patients in EPO maintenance treatment received subcutaneous EPO-ß during the 6-week pre-treatment period to maintain Hb level between 100 g/L and 120 g/L. Eligible patients were randomized (2:1) to accept either C.E.R.A. once every 4 weeks by subcutaneous administration (C.E.R.A. group, n = 187) or subcutaneous EPO-ß 1-3 times weekly (EPO group, n = 94) for 28 weeks (including 20-week dose titration period and 8-week efficacy evaluation period). The starting dose of C.E.R.A. was converted according to the dose of EPO-ß administered in the week preceding the first study drug administration. The primary outcome was the change of Hb level between the baseline and that in the efficacy evaluation period. RESULTS: Totally 253 patients completed the whole 28-week treatment. The change of baseline-adjusted mean Hb was +2.57 g/L for C.E.R.A. group and +1.23 g/L for EPO group, resulting in a treatment difference of 1.34 g/L (95%CI -1.11 - 3.78 g/L). Since the lower limit of 95%CI was greater than the pre-defined non-inferiority margin -7.5 g/L (P < 0.0001), C.E.R.A. once every 4 weeks by subcutaneous administration was clinically non-inferior to EPO regarding the maintenance of stable Hb level. The proportion of patients maintaining Hb level within the range of 100-120 g/L through efficacy evaluation period was similar between the two groups (69.0% for C.E.R.A. group vs 68.9% for EPO group, P > 0.05). The overall incidence of adverse events was similar between the C.E.R.A.(41.7%) and EPO (46.2%) groups (P > 0.05). The safety findings were in accordance with the patients' primary diseases rather than the administration. CONCLUSIONS: Conversion from EPO to C.E.R.A. once every 4 weeks by subcutaneous injection could maintain the Hb in target level in dialytic patients with renal anemia, and it was non-inferior to EPO. In general, subcutaneous administration of C.E.R.A. is well tolerated in dialytic patients with chronic renal anemia.

Treatment of nitrate containing wastewater by adsorption process using polypyrrole-modified plastic-carbon: Characteristic and mechanism.

Polypyrrole-modified plastic-carbon (PET-PPy) composite was prepared by using high porosity plastic-carbon materials and a special doping mechanism of polypyrrole to remove nitrate from water to achieve waste recycling. As a result, PET-PPy-500 showed remarkable nitrate adsorption in both acidic and alkaline wastewater. The pseudo-second-order kinetic and Langmuir isotherm models were fit for the nitrate adsorption by PET-PPy-500, and the maximum adsorption capacity predicted by the Langmuir model was 10.04 mg NO3-N/g (45.18 mg NO3-/g) at 30 °C. The ion exchange and electrostatic attraction were the main mechanisms of removing NO3- by PET-PPy-500, which was demonstrated by the interface characterization and theoretical calculation. The doped ions (Cl-) and/or other anions produced by charge transfer interaction were the main exchange ions in the process of NO3- adsorption. The main binding sites in the electrostatic adsorption process were nitrogen-containing functional groups, which can be confirmed by the results of XPS and density functional theory (DFT). Furthermore, DFT results also showed that the adsorption of nitrate by PET-PPy was a spontaneous exothermic process, and the adsorption energy at the nitrogen site was the lowest. The findings of this study provide a feasible strategy for the advanced treatment of nitrate containing wastewater.

Rice washing drainage (RWD) embedded in poly(vinyl alcohol)/sodium alginate as denitrification inoculum for high nitrate removal rate with low biodiversity.

Immobilization technology with low maintenance is a promising alternative to enhance nitrate removal from water. In this study, washing rice drainage (RWD) was immobilized by poly(vinyl alcohol)/sodium alginate (PVA/SA) to obtain RWD-PVA/SA gel beads as inoculum for denitrification. When initial nitrate concentration was 50 mg N/L, nitrate was effectively removed at rates of 50-600 mg/(L∙d) using acetate as carbon source (C/N = 1.25). Arrhenius activation energy (Ea) of nitrate oxidoreductase was 28.64 kJ/mol for the RWD-PVA/SA gel beads. Temporal and spatial variation in microbial community structures were revealed along with RWD storage and in the reactors by Illumina high-throughput sequencing technology. RWD-PVA/SA gel beads has a simple (operational taxonomic units (OTUs) ã€ˆ100). Dechloromonas, Pseudomonas, Flavobacterium and Acidovorax were the most four dominant genera in the denitrification reactors inoculated with RWD-PVA/SA gel beads. This study provides an inoculum for denitrification with high nitrate removal performance and simple microbial community structures.

Targeted inhibition of osteoclastogenesis reveals the pathogenesis and therapeutics of bone loss under sympathetic neurostress.

Sympathetic cues via the adrenergic signaling critically regulate bone homeostasis and contribute to neurostress-induced bone loss, but the mechanisms and therapeutics remain incompletely elucidated. Here, we reveal an osteoclastogenesis-centered functionally important osteopenic pathogenesis under sympatho-adrenergic activation with characterized microRNA response and efficient therapeutics. We discovered that osteoclastic miR-21 was tightly regulated by sympatho-adrenergic cues downstream the ß2-adrenergic receptor (ß2AR) signaling, critically modulated osteoclastogenesis in vivo by inhibiting programmed cell death 4 (Pdcd4), and mediated detrimental effects of both isoproterenol (ISO) and chronic variable stress (CVS) on bone. Intriguingly, without affecting osteoblastic bone formation, bone protection against ISO and CVS was sufficiently achieved by a (D-Asp8)-lipid nanoparticle-mediated targeted inhibition of osteoclastic miR-21 or by clinically relevant drugs to suppress osteoclastogenesis. Collectively, these results unravel a previously underdetermined molecular and functional paradigm that osteoclastogenesis crucially contributes to sympatho-adrenergic regulation of bone and establish multiple targeted therapeutic strategies to counteract osteopenias under stresses.

[Changes of the upper airway in children with Class â ¡ mandibular retrusion and snoring during night before and after functional treatment by sagittal-guidance Twin-block appliance].

PURPOSE: To study the changes of dimension and morphology of upper airway in children with ClassⅡ mandibular retrusion after functional treatment by sagittal-guidance Twin-block appliance. METHODS: Cone-beam CT (CBCT) data of upper airway of the subjects were measured by Dolphin 11.5 software and Mimics 17.0 software , and the changes of dimension and morphology of upper airway before and after functional treatment with sagittal-guidance Twin-block(SGTB) appliance were compared. SPSS 16.0 software package was used for data processing. RESULTS: After functional treatment，the volume of total upper airway，nasopharynx airway, oropharynx airway, the sectional area of tip of the epiglotti(TE), the lateral diameter of TE, the base of the epiglottis(EB) significantly increased (P<0.05) in children with SGTB appliance. CONCLUSIONS: SGTB functional treatment is effective in the treatment of skeletal ClassⅡ mandibular retrusion of children by increase of the upper airway and improvement of respiration．.

Engineer design process assisted by explainable deep learning network.

Engineering simulation accelerates the development of reliable and repeatable design processes in various domains. However, the computing resource consumption is dramatically raised in the whole development processes. Making the most of these simulation data becomes more and more important in modern industrial product design. In the present study, we proposed a workflow comprised of a series of machine learning algorithms (mainly deep neuron networks) to be an alternative to the numerical simulation. We have applied the workflow to the field of dental implant design process. The process is based on a complex, time-dependent, multi-physical biomechanical theory, known as mechano-regulatory method. It has been used to evaluate the performance of dental implants and to assess the tissue recovery after the oral surgery procedures. We provided a deep learning network (DLN) with calibrated simulation data that came from different simulation conditions with experimental verification. The DLN achieves nearly exact result of simulated bone healing history around implants. The correlation of the predicted essential physical properties of surrounding bones (e.g. strain and fluid velocity) and performance indexes of implants (e.g. bone area and bone-implant contact) were greater than 0.980 and 0.947, respectively. The testing AUC values for the classification of each tissue phenotype were ranging from 0.90 to 0.99. The DLN reduced hours of simulation time to seconds. Moreover, our DLN is explainable via Deep Taylor decomposition, suggesting that the transverse fluid velocity, upper and lower parts of dental implants are the keys that influence bone healing and the distribution of tissue phenotypes the most. Many examples of commercial dental implants with designs which follow these design strategies can be found. This work demonstrates that DLN with proper network design is capable to replace complex, time-dependent, multi-physical models/theories, as well as to reveal the underlying features without prior professional knowledge.

Mechanical properties and in vitro cytocompatibility of dense and porous Ti-6Al-4V ELI manufactured by selective laser melting technology for biomedical applications.

The Ti-6Al-4V alloy is the most common biomaterial used for bone replacements and reconstructions. Despite its advantages, the Ti-6Al-4V has a high stiffness that can cause stress-shielding. In this work, we demonstrated that the selective laser melting (SLM) technology could be used to fabricate porosity in Ti-6Al-4V extra low interstitial (ELI) to reduce its stiffness while improving cell adhesion and proliferation. With a porosity of 14.04%, the elastic modulus of the porous Ti-6Al-4V ELI was reduced to 80 GPa. The compressive stress and the 3-point-bending flexural tests revealed that the porous Ti-6Al-4V ELI possessed a brittle characteristic. The additional pores within the beams of the lattice structures of porous Ti-6Al-4V ELI increased its surface arithmetic average roughness, Ra = 3.94 µm. The in vitro cytocompatibility test showed that the SLM printing process and the post-processes did not cause any toxicity in the MC3T3-E1 cells. The in vitro cell proliferation test also showed that the porous Ti-6Al-4V ELI increased the proliferation rate of osteogenic induced MC3T3-E1 cells on Day 7. The findings from this study would provide engineers and researchers with both the mechanical information and biological understanding of SLM printed porous Ti-6Al-4V ELI, and SLM printed dense Ti-6Al-4V ELI towards biomedical applications.

Human Supernumerary Teeth-Derived Apical Papillary Stem Cells Possess Preferable Characteristics and Efficacy on Hepatic Fibrosis in Mice.

Dental tissue has been acknowledged as an advantaged source for high-quality dental pulp stem cell (DPSC) preparation. However, despite the accomplishment of the separation of DPSCs from permanent teeth and supernumerary teeth, the deficiency of rigorous and systematic clarification on the signatures and efficacy will hinder their prospects in regenerative medicine. In this study, we primitively isolated permanent teeth-derived DPSCs and supernumerary teeth-derived apical papillary stem cells (SCAP-Ss) with parental consent. Immunophenotype of DPSCs and SCAP-Ss was determined by a flow cytometry assay, and the cell viability was verified by multidimensional detections including cell proliferation, cell cycle, apoptosis, and senescence. The migration and clonogenic capacity were examined by a wound healing test and crystal violet staining, respectively. The multilineage differentiation potential was quantitated by utilizing Oil Red O staining and Alizarin Red staining, together with real-time PCR analysis. The efficacy on a mouse hepatic fibrosis model was evaluated by using histologic sections and liver function tests. Herein, we showed that SCAP-Ss exhibited comparable immunophenotype and adipogenic differentiation capacity as DPSCs. However, different from DPSCs, SCAP-Ss exhibited superiority in cell viability and osteogenic differentiation. Simultaneously, injection of DPSCs and SCAP-Ss significantly reduced inflammatory infiltration, enhanced liver-associated gene expression, and finally relieved symptoms of hepatic fibrosis. In conclusion, SCAP-Ss possess preferable characteristics and efficacy on hepatic fibrosis in mice. Our findings suggest that SCAP-Ss are an easily accessible postnatal stem cell source with multifaceted characteristics for regenerative medicine.

Using Multilayered Hydrogel Bioink in Three-Dimensional Bioprinting for Homogeneous Cell Distribution.

During the extrusion-based three-dimensional bioprinting process, liquid-like bioinks with low viscosity can protect cells from membrane damage induced by shear stress and improve the survival of the encapsulated cells. However, rapid gravity-driven cell sedimentation in the reservoir could lead to an inhomogeneous cell distribution in bioprinted structures and therefore hinder the application of liquid-like bioinks. Here, we developed a novel multilayered modified strategy for liquid-like bioinks (e.g., gelatin methacryloyl with low viscosity) to prevent the sedimentation of encapsulated cells. Multiple liquid interfaces were manipulated in the multilayered bioink to provide interfacial retention. Consequently, the cell sedimentation action going across adjacent layers in the multilayered system was retarded in the bioink reservoir. It was found that the interfacial retention was much higher than the sedimental pull of cells, demonstrating a critical role of the interfacial retention in preventing cell sedimentation and promoting a more homogeneous dispersion of cells in the multilayered bioink.

Biodegradable Bacterial Cellulose-Supported Quasi-Solid Electrolyte for Lithium Batteries.

The stringent safety and sustainability requirements for electrolytes used in lithium batteries have led to significant research efforts into alternative materials. Here, a quasi-solid electrolyte based on biodegradable bacterial cellulose (BC) was successfully synthesized via a simple ball milling method. The BC provides plenty of sites for the attachment of ionic liquid electrolytes (ILEs) as well as ion transport channels. Moreover, the O-H groups contained in the BC molecular chains interact with anions in ILEs to form hydrogen bonds, which promotes the dissociation of the lithium salts. The prepared electrolytes (BC-ILEs) have good thermal stability with a decomposition temperature exceeding 300 °C and high ionic conductivities. The Li/BC-ILE/LiFePO4 battery exhibits remarkable electrochemical performance. More importantly, the results of the Fehling test verify that the electrolyte can be degraded by cellulase. The quasi-solid electrolyte broadens the range of electrolytes for lithium batteries and provides new avenues to explore safe and eco-friendly materials.

Live-cell imaging of octaarginine-modified polymer dots via single particle tracking.

OBJECTIVES: Nanocarriers can greatly enhance the cellular uptake of therapeutic agents to regulate cell proliferation and metabolism. Nevertheless, further application of nanocarriers is often limited by insufficient understanding of the mechanisms of their uptake and intracellular behaviour. MATERIALS AND METHODS: Fluorescent polymer dots (Pdots) are coated with synthetic octaarginine peptides (R8) and are analysed for cellular uptake and intracellular transportation in HeLa cervical cancer cells via single particle tracking. RESULTS: Surface modification with the R8 peptide efficiently improves both cellular uptake and endosomal escape of Pdots. With single particle tracking, we capture the dynamic process of internalization and intracellular trafficking of R8-Pdots, providing new insights into the mechanism of R8 in facilitating nanostructure-based cellular delivery. Furthermore, our results reveal R8-Pdots as a novel type of autophagy inducer. CONCLUSIONS: This study provides new insights into R8-mediated cellular uptake and endosomal escape of nanocarriers. It potentiates biological applications of Pdots in targeted cell imaging, drug delivery and gene regulation.