Characterizing Anti-Vaping Posts for Effective Communication on Instagram Using Multimodal Deep Learning.

INTRODUCTION: Instagram is a popular social networking platform for sharing photos with a large proportion of youth and young adult users. We aim to identify key features in anti-vaping Instagram image posts associated with high social media user engagement by artificial intelligence. AIMS AND METHODS: We collected 8972 anti-vaping Instagram image posts and hand-coded 2200 Instagram images to identify nine image features such as warning signs and person-shown vaping. We utilized a deep-learning model, the OpenAI: contrastive language-image pre-training with ViT-B/32 as the backbone and a 5-fold cross-validation model evaluation, to extract similar features from the Instagram image and further trained logistic regression models for multilabel classification. Latent Dirichlet Allocation model and Valence Aware Dictionary and sEntiment Reasoner were used to extract the topics and sentiment from the captions. Negative binomial regression models were applied to identify features associated with the likes and comments count of posts. RESULTS: Several features identified in anti-vaping Instagram image posts were significantly associated with high social media user engagement (likes or comments), such as educational warnings and warning signs. Instagram posts with captions about health risks associated with vaping received significantly more likes or comments than those about help quitting smoking or vaping. Compared to the model based on 2200 hand-coded Instagram image posts, more significant features have been identified from 8972 AI-labeled Instagram image posts. CONCLUSION: Features identified from anti-vaping Instagram image posts will provide a potentially effective way to communicate with the public about the health effects of e-cigarette use. IMPLICATIONS: Considering the increasing popularity of social media and the current vaping epidemic, especially among youth and young adults, it becomes necessary to understand e-cigarette-related content on social media. Although pro-vaping messages dominate social media, anti-vaping messages are limited and often have low user engagement. Using advanced deep-learning and statistical models, we identified several features in anti-vaping Instagram image posts significantly associated with high user engagement. Our findings provide a potential approach to effectively communicate with the public about the health risks of vaping to protect public health.

Constitutive Activation of ß-Catenin in Differentiated Osteoclasts Induces Bone Loss in Mice.

BACKGROUND/AIMS: Activation of the Wnt/ß-catenin signalling pathway has been widely investigated in bone biology and shown to promote bone formation. However, its specific effects on osteoclast differentiation have not been fully elucidated. Our study aimed to identify the role of ß-catenin in osteoclastogenesis and bone homeostasis. METHODS: In the present study, exon 3 in the ß-catenin gene (Ctnnb1) allele encoding phosphorylation target serine/threonine residues was flanked by floxP sequences. We generated mice exhibiting conditional ß-catenin activation (Ctsk-Cre;Ctnnb1flox(exon3)/+, designated CA-ß-catenin) by crossing Ctnnb1flox(exon3)/flox(exon3) mice with osteoclast-specific Ctsk-Cre mice. Bone growth and bone mass were analysed by micro-computed tomography (micro-CT) and histomorphometry. To further examine osteoclast activity, osteoclasts were induced from bone marrow monocytes (BMMs) isolated from CA-ß-catenin and Control mice in vitro. Osteoclast differentiation was detected by tartrate-resistant acid phosphatase (TRAP) staining, immunofluorescence staining and reverse transcription-quantitative PCR (RT-qPCR) analysis. RESULTS: Growth retardation and low bone mass were observed in CA-ß-catenin mice. Compared to controls, CA-ß-catenin mice had significantly reduced trabecular bone numbers under growth plates as well as thinner cortical bones. Moreover, increased TRAP-positive osteoclasts were observed on the surfaces of trabecular bones and cortical bones in the CA-ß-catenin mice; consistent results were observed in vitro. In the CA-ß-catenin group, excessive numbers of osteoclasts were induced from BMMs, accompanied by the increased expression of osteoclast-associated marker genes. CONCLUSION: These results indicated that the constitutive activation of ß-catenin in osteoclasts promotes osteoclast formation, resulting in bone loss.

Constitutive activation of ß-catenin in odontoblasts induces aberrant pulp calcification in mouse incisors.

During dentin formation, odontoblast polarization ensures that odontoblasts directionally secrete dentin matrix protein, leading to tubular dentin formation; however, little is known about the major features and regulatory mechanisms of odontoblast polarization. In a study of epithelial cell polarization, ß-catenin was shown to serve as a structural component of cadherin-based adherens junctions to initiate cell polarity. However, the role of ß-catenin in odontoblast polarization has not been well investigated. In this study, we explored whether ß-catenin participated in odontoblast polarization to regulate the secretion of mineralization proteins. We established Col1-CreErt2; ß-catenin exon3fl/fl (CA-ß-catenin) mice, which constitutively activate ß-catenin in odontoblasts. CA-ß-catenin mice exhibited disorganization and depolarization of incisor odontoblasts. Moreover, the incisor dentin was hypomineralized, and ectopic calcification was found in mouse incisor pulp. In addition, by constitutive activation of ß-catenin, the expression levels of the core polarity molecule Cdc42 and its downstream polarity protein complex Par3-Par6-aPKC were decreased in the incisors of CA-ß-catenin mice. These findings suggest that ß-catenin plays an essential role in dentin formation by regulating odontoblast polarization.

Osteoprotegerin deficiency causes morphological and quantitative damage in epithelial rests of Malassez.

Epithelial rests of Malassez (ERM), the only odontogenic epithelial structures in periodontal tissue, are proposed to correlate with root resorption, but the detailed mechanism remains unclear. Osteoprotegerin (OPG), the main inhibitor of osteoclastogenesis, plays a pivotal role in inhibiting root resorption, and ERM cells express OPG mRNA in vitro. Thus, in this study, we aimed to clarify OPG expression in ERM in vivo and to explore the role of OPG in ERM to determine whether ERM are associated with root resorption via OPG. We established Opg-knockout (Opg-KO) mice and detected the OPG expression in ERM by immunohistochemical staining in 4-, 6-, 10-, 26- and 52-week-old mice. The ERM of wild-type (WT) mice and Opg-KO mice were evaluated histologically at 4, 10 and 26 weeks of age. Orthodontic root resorption models were established, maxillae were collected after 4 weeks, and ERM were analysed by histomorphometric analysis. In our study, OPG displayed sustained expression in ERM, and OPG deficiency caused the destruction of ERM, characterized by irregular morphology and reduced numbers. Moreover, after orthodontic treatment, the loss of OPG severely damaged ERM, aggravating root resorption. Together, our results demonstrated that ERM expressed the OPG protein in vivo and that OPG deficiency resulted in morphological and quantitative damage to ERM. Furthermore, ERM may be associated with root resorption via OPG, thus helping to explain the mechanism underlying root resorption.

Constitutive activation of ß-catenin in ameloblasts leads to incisor enamel hypomineralization.

Enamel is the hardest tissue with the highest degree of mineralization protecting the dental pulp from injury in vertebrates. The ameloblasts differentiated from ectoderm-derived epithelial cells are a single cell layer and are important for the enamel formation and mineralization. Wnt/ß-catenin signaling has been proven to exert an important role in the mineralization of bone, dentin and cementum. Little was known about the regulatory mechanism of Wnt/ß-catenin signaling pathway in ameloblasts during amelogenesis, especially in the mineralization of enamel. To investigate the role of ß-catenin in ameloblasts, we established Amelx-Cre; ß-catenin∆ex3fl/fl (CA-ß-catenin) mice, which could constitutive activate ß-catenin in ameloblasts. It showed the delayed mineralization and eventual hypomineralization in the incisor enamel of CA-ß-catenin mice. Meanwhile, the amelogenesis-related proteinases Mmp20 and Klk4 were decreased in the incisors of CA-ß-catenin mice. These data indicated that ß-catenin plays an essential role in differentiation and function of ameloblasts during amelogenesis.

Osteoprotegerin-Knockout Mice Developed Early Onset Root Resorption.

INTRODUCTION: Recent studies indicate that the osteoprotegerin (OPG)/RANKL/RANK pathway takes part in root resorption. However, the relationship between OPG and root resorption is vague. The purpose of our study was to investigate the role of OPG in root resorption. METHODS: The first molars of the mandibles of osteoprotegerin-knockout (Opg-KO) mice and wild-type (WT) mice were evaluated by micro-computed tomography, histology, and immunohistochemistry at 4, 6, 26, and 52 weeks. To detect the activity of the osteoclasts, we induced bone marrow macrophages into osteoclast-like cells from Opg-KO mice and wild-type mice in vitro and then compared their osteoclast activities. To evaluate the cementum quality, an osteoclast-cementum co-culture model was established in vitro. RESULTS: In Opg-KO mice, root resorption began at the age of 4 weeks. At 6 weeks the cementum damage extended to the coronal and apical regions, and at 52 weeks the damage reached the predentin. At all observed stages, more tartrate-resistant acid phosphatase (TRAP)-positive cells were found on the surface of cementum in Opg-KO mice. In vitro, the mRNA levels of cathepsin K, TRAP, matrix metalloproteinase-9, and matrix metalloproteinase-1, as well as the protein expression of nuclear factor of activated T cell 1 and TRAP, increased significantly in osteoclast-like cells from Opg-KO mice. In addition, the cementum resorption pits of Opg-KO mice were larger when co-cultured with osteoclast-like cells. CONCLUSIONS: Our study demonstrated that loss of OPG led to root resorption via increasing activation of osteoclasts and reducing mineralization of cementum.

[An overview on studies of soil organic matter in Chinese fir plantation].

Soil organic matter (SOM) is an important component of soil and an important carbon pool of terrestrial ecosystems, which plays an important role in soil nutrient cycling and in the balance of global carbon cycle. This paper discussed the SOM quality in Chinese fir plantation, the influence of rotation on SOM content, the change of SOM during Chinese fir growth, and the effect of human activities such as burning, site preparations and fertilization on SOM. Human activities changed soil environment including soil moisture, temperature, total porosity and nutrient contents, and hence, made the turnover of SOM slower or quicker. The content and quality of SOM in mixed forests were higher than those in pure Chinese fir plantations, and decreased with rotation. In the last part of this paper, some issues to be further researched were put forward, including the turnover model of SOM, its components, and its relationship with global carbon cycle.