The moderating effect of environmental gamification on the relationship between social media marketing and consumer-brand engagement: A case study of Ant Forest Gen Z users.

Social media marketing plays a relevant role in the brand promotion of enterprises owing to its advantages of rapid and diversified communication with consumers. The Chinese Internet enterprise Alipay launched Ant Forest as a mobile application with gamified social functions, bringing consumer-brand engagement. Ant Forest provides a variety of gamification functions (e.g. point, leaderboard, badge, task and teamwork) to encourage users to participate in environmental protection and public welfare activities. These gamification mechanisms, combined with the spread of social media, have realised the co-creation of user brand value. In the current study, 305 Gen Z users of Ant Forest were surveyed through an online questionnaire, and the data analysis was conducted using the partial least squares structural equation modelling (PLS-SEM) method. This study indicates that the four elements of entertainment, trendiness, customisation and word-of-mouth in social media marketing have statistically significant direct effects on the consumer-brand engagement in Ant Forest. In addition, gamification shows a significant positive moderating effect on the relationship between customisation and consumer-brand engagement and a significant negative moderating effect on the relationship between trendiness and consumer-brand engagement in Ant Forest. This study adds gamification to the conceptual system of social media marketing and provides suggestions for the development of gamified social media marketing applications.

A Polyanionic Tartrate-containing Temperature-responsive Hydrogel.

Thermogels, a class of hydrogels which show spontaneous sol-gel phase transition when warmed, are an important class of soft biomaterials. To date, however, most amphiphilic polymers that are able to form thermogels in aqueous solution are uncharged, and the influence of ionisable groups on thermogelation are largely unknown. Herein, we report the first example of a polyanionic amphiphilic multi-block copolymer, containing multiple pendant carboxylate groups, that can form transparent thermogels spontaneously when warmed up to physiological temperature. We demonstrate that introducing negative charges onto thermogelling polymers could significantly alter the properties of the micelles and thermogels formed. Furthermore, the polymer's polyanionic character provides new options for modulating the gel rheological properties, such as stiffness and gelation temperatures, through electrostatic interactions with different cations. We also demonstrated that the polyanionic thermogel allowed slower sustained release of a cationic model drug compound compared to an anionic one over 2 weeks. The findings from our study demonstrate exciting new possibilities for advanced biomedical applications using charged polyelectrolyte thermogel materials.

A chelator-free multifunctional [64Cu]CuS nanoparticle platform for simultaneous micro-PET/CT imaging and photothermal ablation therapy.

We synthesized and evaluated a novel class of chelator-free [(64)Cu]CuS nanoparticles (NPs) suitable both for PET imaging and as photothermal coupling agents for photothermal ablation. These [(64)Cu]CuS NPs are simple to make, possess excellent stability, and allow robust noninvasive micro-PET imaging. Furthermore, the CuS NPs display strong absorption in the near-infrared (NIR) region (peak at 930 nm); passive targeting prefers the tumor site, and mediated ablation of U87 tumor cells occurs upon exposure to NIR light both in vitro and in vivo after either intratumoral or intravenous injection. The combination of small diameter (∼11 nm), strong NIR absorption, and integration of (64)Cu as a structural component makes these [(64)Cu]CuS NPs ideally suited for multifunctional molecular imaging and therapy.

Receptor-mediated transcytosis: a mechanism for active extravascular transport of nanoparticles in solid tumors.

Targeted nanoparticle-based delivery systems have been used extensively to develop effective cancer theranostics. However, how targeting ligands affect extravascular transport of nanoparticles in solid tumors remains unclear. Here, we show, using B16/F10 melanoma cells expressing melanocortin type-1 receptor (MC1R), that the nature of targeting ligands, i.e., whether they are agonists or antagonists, directs tumor uptake and intratumoral distribution after extravasation of nanoparticles from tumor vessels into the extravascular fluid space. Pegylated hollow gold nanospheres (HAuNS, diameter=40 nm) coated with MC1R agonist are internalized upon ligand-receptor binding, whereas MC1R antagonist-conjugated HAuNS remain attached on the cell surface. Transcellular transport of agonist-conjugated HAuNS was confirmed by a multilayer tumor cell model and by transmission electron microscopy. MC1R agonist- but not MC1R antagonist-conjugated nanoparticles exhibit significantly higher tumor uptake than nontargeted HAuNS and are quickly dispersed from tumor vessels via receptor-mediated endocytosis and subsequent transcytosis. These results confirm an active transport mechanism that can be used to overcome one of the major biological barriers for efficient nanoparticle delivery to solid tumors.

[Application of spiral CT three-dimensional reconstruction in treatment planning of impacted teeth].

OBJECTIVE: To assess the value of three-dimensional (3D) reconstruction in treatment planning of impacted teeth. METHODS: Thirty-two orthodontic patients with impacted teeth aged from 13 to 17 years were enrolled, including 15 with impacted maxillary canines, 8 with impacted premolars and 6 with second molar impaction and retention. All the impacted teeth were examined by spiral CT scan and 3D reconstruction to determine the 3D position of the tooth in relation to both the crown and root, and the proximity to the roots of other teeth. The data were used for treatment planning and determination of the suitable direction of the orthodontic forces, approaches of surgical exposure, and the position of the attachment to be bonded. RESULTS: Normal occlusion was achieved for 15 patients with transposition maxillary canines and 5 with lower position premolar. Three malformed premolars were extracted after traction. For 9 patients with second molar impaction and retention, normal occlusion was achieved after extraction of the third molar or moving the first molar mesial. CONCLUSION: Spiral CT scan and 3D reconstruction can accurately determine the 3D position of the impacted tooth and provide assistance in the treatment planning to achieve a higher success rate of orthodontic correction.

[Relationship between masseter muscle electromyographic activities and the position of the mandible].

OBJECTIVE: To investigate the changes in electromyographic activities of the temporal and masseter muscles at different positions of the mandible. METHODS: Twenty orthodontic patients with Angle Class II malocclusion and mandibular retrusion (ANB<6°) aged 10-14 years were enrolled in this study. All the patients were treated with Forsus fixed functional appliance combined with MBT straight-wire appliance. The electromyographic activities of the temporal (T) and masseter (M) muscles before, during and after functional treatment were evaluated by assessing the average integrated electromyogram (EMG) and T/M ratio at clenching status in different mandibular positions. RESULTS: After functional forward positioning of the mandible, the electromyographic activities of the temporal and masseter muscles decreased and T/M ratio increased significance at the clenching status (P<0.05). CONCLUSION: The appliance insertion and activation is associated with a decreased EMG activity of the temporal and masseter muscles, and the T/M ratio is correlated to the position of the mandible.

Peptide-conjugated polymeric micellar nanoparticles for Dual SPECT and optical imaging of EphB4 receptors in prostate cancer xenografts.

EphB4, a member of the largest family of receptor tyrosine kinases, is overexpressed in numerous tumors. In this study, we developed a new class of multimodal nanoplatform for dual single photon emission computed tomography (SPECT) and near-infrared fluorescence imaging of EphB4. EphB4-binding peptide TNYL-FSPNGPIARAW (TNYL-RAW) was conjugated to polyethylene glycol-coated, core-crosslinked polymeric micelles (CCPM) dually labeled with near-infrared fluorescence fluorophores (Cy7) and a radioisotope (indium 111). In vitro, TNYL-RAW-CCPM selectively bound to EphB4-positive PC-3M prostate cancer cells, but not to EphB4-negative A549 lung cancer cells. In vivo, PC-3M tumors were clearly visualized by both SPECT and near-infrared fluorescence tomography after intravenous administration of (111)In-labeled TNYL-RAW-CCPM. In contrast, there was little signal in A549 tumors of mice injected with (111)In-labeled TNYL-RAW-CCPM or in PC-3M tumors of mice injected with (111)In-labeled CCPM. The high accumulation of (111)In-labeled TNYL-RAW-CCPM in PC-3M tumor could be significantly reduced after co-injection with an excess amount of TNYL-RAW peptide. Immunohistochemical analysis showed that fluorescence signal from the nanoparticles correlated with their radioactivity count, and co-localized with the EphB4 expressing region. (111)In-labeled TNYL-RAW-CCPM allowed visualization of cancer cells overexpressing EphB4 by both nuclear and optical techniques. The complementary information acquired with multiple imaging techniques should be advantageous in early detection of cancer.

Annexin A5-conjugated polymeric micelles for dual SPECT and optical detection of apoptosis.

UNLABELLED: Imaging of apoptosis can allow noninvasive assessment of disease states and response to therapeutic intervention for a variety of diseases. The purpose of this study was to develop and evaluate a multimodal nanoplatform for the detection of apoptosis. METHODS: To modulate the pharmacokinetics of annexin A5, a 36-kDa protein that binds specifically with phosphatidylserine, annexin A5 was conjugated to polyethylene glycol-coated, core-cross-linked polymeric micelles (CCPMs) dually labeled with near-infrared fluorescence fluorophores and a radioisotope ((111)In). To evaluate the specificity of the binding of annexin A5-CCPM to apoptotic cells, both fluorescence microscopy and cell-binding studies were performed in vitro. Pharmacokinetics, biodistribution, dual nuclear and optical imaging, and immunohistochemical studies were performed in 2 xenografted tumor models to evaluate the potential applications of annexin A5-CCPM. RESULTS: In cell-based studies, annexin A5-CCPM exhibited strongly specific binding to apoptotic tumor cells. This binding could be efficiently blocked by annexin A5. In mice, annexin A5-CCPM displayed a mean elimination half-life of 12.5 h. The mean initial concentration in blood was 22.4% of the injected dose/mL, and annexin A5-CCPM was mainly distributed in the central blood compartment. In mice bearing EL4 lymphoma treated with cyclophosphamide and etoposide and in mice bearing MDA-MB-468 breast tumors treated with poly(L-glutamic acid)-paclitaxel and cetuximab (IMC-C225) anti-epidermal growth factor receptor antibody, the tumor apoptosis was clearly visualized by both SPECT and fluorescence molecular tomography. In contrast, there was little accumulation of this nanoradiotracer in the tumors of untreated mice. The biodistribution data were consistent with the imaging data, with tumor-to-muscle and tumor-to-blood ratios of 38.8 and 4.1, respectively, in treated mice, and 14.8 and 2.2, respectively, in untreated mice bearing EL4 lymphoma. Moreover, further studies demonstrated that the conventional (99m)Tc-labeled hydrazinonicotinamide annexin A5 and the plain CCPM control exhibited significantly lower uptake in the tumors of the treated mice than annexin A5-CCPM. Immunohistochemistry staining study showed that radioactivity count correlated with fluorescence signal from the nanoparticles, and both signals colocalized with the region of tumor apoptosis. CONCLUSION: Annexin A5-CCPM allowed visualization of tumor apoptosis by both nuclear and optical techniques. The complementary information acquired with multiple imaging techniques should be advantageous in assessing and validating early response to therapy.