The dynamic progression of temporomandibular joint osteoarthritis-like lesions elicited by mandibular shift in a rat model.

BACKGROUND: Temporomandibular joint osteoarthritis (TMJ-OA) presents significant challenges due to its complex etiology, often insidious onset, high incidence, and progressive structural deterioration. While research has explored genetic and molecular factors, treatment outcomes remain suboptimal, emphasizing the need for a deeper understanding of disease progression. OBJECTIVE: This study employs a specific mandibular shift rat model to explore the dynamic progression of TMJ-OA-like lesions and evaluate the potential for self-repair at different stages, aiming to inform early diagnosis and preventative strategies. METHODS: Seventy-two female Sprague-Dawley rats were randomized into three groups: a control group (n=24; average weight: 157.23±1.63 g) receiving sham surgery. an experimental group (n=24; average weight: 157.78±1.88 g) subjected to mandibular shift induction, and a removal group (n=24; average weight: 158.11±2.20 g) experiencing mandibular shift for one, two, or four weeks followed by a one-month recovery period (designated as 1w Removal, 2w Removal and 4w Removal, respectively). Histomorphological and molecular analyses were conducted at designated time points. RESULTS: Rats in the 1-week removal group exhibited substantial recovery in condylar morphology, cartilage thickness, extracellular matrix composition, and expression of OA-related genes. Conversely, the 4-week removal group mirrored the experimental group, indicating limited self-repair capacity at later stages. The 2-week removal group presented with variable outcomes, with some animals showing signs of recovery and others resembling the experimental group, indicating a potential transitional phase in the disease process. CONCLUSION: Recovery from early-stage TMJ-OA involves eliminating provoking factors such as occlusal interference or reducing joint loading. However, advanced stages exhibit diminished self-repair capabilities, necessitating additional therapeutic interventions. These findings emphasize the importance of early diagnosis and intervention in TMJ-OA management.

Exploring new avenues of health protection: plant-derived nanovesicles reshape microbial communities.

Symbiotic microbial communities are crucial for human health, and dysbiosis is associated with various diseases. Plant-derived nanovesicles (PDNVs) have a lipid bilayer structure and contain lipids, metabolites, proteins, and RNA. They offer unique advantages in regulating microbial community homeostasis and treating diseases related to dysbiosis compared to traditional drugs. On the one hand, lipids on PDNVs serve as the primary substances that mediate specific recognition and uptake by bacteria. On the other hand, due to the multifactorial nature of PDNVs, they have the potential to enhance growth and survival of beneficial bacterial while simultaneously reducing the pathogenicity of harmful bacteria. In addition, PDNVs have the capacity to modulate bacterial metabolism, thus facilitating the establishment of a harmonious microbial equilibrium and promoting stability within the microbiota. These remarkable attributes make PDNVs a promising therapeutic approach for various conditions, including periodontitis, inflammatory bowel disease, and skin infection diseases. However, challenges such as consistency, isolation methods, and storage need to be addressed before clinical application. This review aims to explore the value of PDNVs in regulating microbial community homeostasis and provide recommendations for their use as novel therapeutic agents for health protection.

Exploring the Role of Wnt Ligands in Osteogenic Differentiation of Human Periodontal Ligament Stem Cells.

OBJECTIVES: This study aimed to investigate the functions of 19 types of Wnt ligands during the process of osteogenic differentiation in human periodontal ligament stem cells (hPDLSCs), with particular attention to WNT3A and WNT4. MATERIALS AND METHODS: The expression levels of 19 types of Wnt ligands were examined using real-time quantitative polymerase chain reaction (real-time qPCR) during hPDLSCs osteogenic differentiation at 7, 10, and 14 days. Knockdown of WNT3A and WNT4 expression was achieved using adenovirus vectors, and conditioned medium derived from WNT3A and WNT4 overexpression plasmids was employed to investigate their roles in hPDLSCs osteogenesis. Osteogenic-specific genes were analyzed using real-time qPCR. Alkaline phosphatase (ALP) and alizarin red S activities and staining were employed to assess hPDLSCs' osteogenic differentiation ability. RESULTS: During hPDLSCs osteogenic differentiation, the expression of 19 types of Wnt ligands varied, with WNT3A and WNT4 showing significant upregulation. Inhibiting WNT3A and WNT4 expression hindered hPDLSCs' osteogenic capacity. Conditioned medium of WNT3A promoted early osteogenic differentiation, while WNT4 facilitated late osteogenesis slightly. CONCLUSION: Wnt ligands, particularly WNT3A and WNT4, play an important role in hPDLSCs' osteogenic differentiation, highlighting their potential as promoters of osteogenesis. CLINICAL RELEVANCE: Given the challenging nature of alveolar bone regeneration, therapeutic strategies that target WNT3A and WNT4 signaling pathways offer promising opportunities. Additionally, innovative gene therapy approaches aimed at regulating of WNT3A and WNT4 expression hold potential for improving alveolar bone regeneration outcomes.

Plant-derived nanovesicles: harnessing nature's power for tissue protection and repair.

Tissue damage and aging lead to dysfunction, disfigurement, and trauma, posing significant global challenges. Creating a regenerative microenvironment to resist external stimuli and induce stem cell differentiation is essential. Plant-derived nanovesicles (PDNVs) are naturally bioactive lipid bilayer nanovesicles that contain proteins, lipids, ribonucleic acid, and metabolites. They have shown potential in promoting cell growth, migration, and differentiation into various types of tissues. With immunomodulatory, microbiota regulatory, antioxidant, and anti-aging bioactivities, PDNVs are valuable in resisting external stimuli and facilitating tissue repair. The unique structure of PDNVs provides an optimal platform for drug encapsulation, and surface modifications enhance their stability and specificity. Moreover, by employing synergistic administration strategies, PDNVs can maximize their therapeutic potential. This review summarized the progress and prospects of PDNVs as regenerative tools, provided insights into their selection for repair activities based on existing studies, considered the key challenge for clinical application, and anticipated their continued prominent role in the field of biomedicine.

Identification of biomarkers related to prognosis and diagnosis of periodontitis by bioinformatics based on public database.

OBJECTIVES: Periodontitis is a multifactorial disease that has a negative impact on people's life. However, studies on potential key genes with excellent diagnostic value for periodontitis disease have not been systematically explored. METHODS: GSE10334 data set was downloaded from the Gene Expression Omnibus database. Following the gene expression profiles were normalized by the Robust multi-array average (RMA) algorithm, the differentially expressed genes were screened and incorporated into Weight gene correlation network analysis to obtain hub genes. Receiver-operating characteristic curve analysis was used to verify the validity and agility of the hub genes-based least absolute shrinkage and selection operator model. Furthermore, we validated the expression of these hub genes by real-time polymerase chain reaction and western blotting. RESULTS: Eight hub genes were identified and had good diagnostic values. Besides, the upregulations of eight hub genes were verified both in protein and mRNA levels in clinical periodontitis gum tissue. CONCLUSION: We discovered potential biomarkers in periodontitis based on the public database and these biomarkers focused on several immune responses and inflammatory pathways. Thus, this study may provide potential therapeutic targets for early diagnosis and treatment of periodontitis.

Stratified changes in emotional distress during the COVID-19 pandemic: Evidence from a longitudinal survey of residents in Hubei province, China.

BACKGROUND: The COVID-19 pandemic has had a significant impact on individuals' emotional wellbeing and mental health. However, little research has examined emotional resilience during the pandemic. This study investigated the changes in emotional distress among residents in Hubei, the epicenter of the pandemic in China during the early stage of the pandemic, and we examined the sociodemographic differences in their emotional recovery. METHODS: We undertook a two-wave panel survey of 3816 residents aged ≥18 in Hubei, China. The baseline survey was conducted during early February 2020, the peak of the outbreak. The follow-up survey was carried out when the pandemic was mainly under control. The data enabled us to investigate the within-person changes in COVID-19-related negative emotions. Mixed-effect regression models with a random effect for participants were used to accommodate repeated measures. RESULTS: Respondents reported high levels of emotional distress at the peak of the pandemic and experienced a decline in emotional distress when the pandemic was under control. Moreover, respondents aged 35-49, with a college education or above, were employed, and having better self-rated health experienced a more substantial decrease in negative emotions during the COVID-19 pandemic. CONCLUSION: This study identified vulnerable populations who may experience prolonged emotional distress during the COVID-19 pandemic in China. The results suggest that respondents who aged over 50, with no college education, were not employed, and with worse self-rated health were less resilient during the COVID-19 pandemic in China.

Effects of changes in physical and sedentary behaviors on mental health and life satisfaction during the COVID-19 pandemic: Evidence from China.

BACKGROUND: While restriction measures are critical in containing the COVID-19 outbreak, limited studies have investigated the behavioral and psychological impact of these measures. This study aimed to investigate the effects of physical and sedentary behavioral changes and online behavior during the COVID-19 pandemic on mental health and life satisfaction among the Chinese population. METHODS: The data were obtained from a cross-sectional survey of 2145 residents aged between 18 and 80 in Hubei province, China between March 23, 2020, and April 9, 2020. RESULTS: Participants who had high frequencies of physical activities before or during the COVID-19 outbreak exhibited higher levels of life satisfaction. Participants who increased their sitting time during the pandemic or kept sitting for more than eight hours before and during the pandemic reported worse mental health than those who maintained less sedentary behavior. Besides, participants who used the Internet for information seeking, communication, and entertainment more frequently reported better mental health and life satisfaction. In contrast, there was a positive association between commercial use of the Internet and symptoms of mental disorders. CONCLUSION: Given the link between physical and sedentary behavioral changes with worse mental wellbeing, strategies to reduce sedentariness and increase physical activity during the COVID-19 pandemic are needed.

Effects of functional mandibular lateral shift on craniofacial growth and development in growing rats.

BACKGROUND: Unilateral posterior crossbite, one of the most frequent malocclusions, is often associated with functional lateral shift of the mandible. Although the effects of functional lateral shift on the mandible and temporomandibular joint have been examined in various animal experiments, cranial and maxillary changes have received less attention. OBJECTIVE: The aim of this study was to investigate the effects of functional lateral shift on the craniofacial complex in growing rats. METHODS: Eighty 5-week-old male Sprague-Dawley rats were randomly divided into an experimental group (n = 40), which received an oblique guide appliance that shifted the mandible to the left during closure, and a control group (n = 40). The rats were scanned by cone-beam computed tomography at 3 days and 1, 2, 4 and 8 weeks. The dimensions of the mandibular bone, condyle, maxilla and cranium were measured. RESULTS: The mandibles of rats in the experimental group were smaller than those of the rats in the control group and were asymmetrical. The condyles of the rats in the experimental group were thinner than those of the control rats. The condylar length on the ipsilateral side was shorter and wider than that on the contralateral side from 4 to 8 weeks. No significant differences in cranial length or height were observed between the experimental and control groups. The height of the upper first molar and alveolar bone on the contralateral side was significantly smaller than that on the ipsilateral side and in the controls from 4 to 8 weeks. CONCLUSION: Functional shift in the mandible produces morphological asymmetries in the mandible and maxillary region and may cause bilateral condylar degenerative changes.

Mechanical stress reduces secreted frizzled-related protein expression and promotes temporomandibular joint osteoarthritis via Wnt/ß-catenin signaling.

AIMS: Mechanical stress overload in the temporomandibular joint (TMJ) is an important cause of TMJ osteoarthritis (TMJOA). Whether secreted frizzled-related proteins (SFRPs) play important roles in the development of mechanical stress-induced TMJOA remains controversial. In this study, we investigated the roles of the Wnt/ß-catenin signaling and SFRPs in the progression of mechanical stress-induced TMJOA. METHODS: We investigated the progression of mechanical stress-induced TMJOA using an in vivo model via modified increased occlusal vertical dimension (iOVD) malocclusion and an in vitro model in which isolated chondrocytes were subjected to mechanical stress. The effects of inhibition of Wnt/ß-catenin signal on TMJOA induced by mechanical stress were studied by in vitro drug added and in vivo intra-articular injection of XAV-939. TMJOA progression, Wnt/ß-catenin signaling and SFRPs was assessed by Cone beam computed tomography (CBCT) analysis, histochemical and immunohistochemical (IHC) staining, quantitative real-time PCR (qRT-PCR), Western blotting (WB), and immunofluorescence (IF) staining. RESULTS: Our in vivo results showed that iOVD-induced mechanical stress in the TMJ disrupted mandible growth, induced OA-like changes in TMJ cartilage, and increased OA-related cytokine expression. In addition, iOVD activated Wnt/ß-catenin signaling and suppressed Sfrp1, Sfrp3, and Sfrp4 expression in condylar cartilage. Moreover, our in vitro study showed that stress disrupted homeostasis, activated Wnt/ß-catenin signaling and inhibited SFRP3 and SFRP4 expression in chondrocytes. Suppression of Wnt/ß-catenin signaling with XAV-939 promoted SFRP3 and SFRP4 expression and rescued mechanical stress-induced cartilage degeneration in vivo and in vitro. CONCLUSIONS: Our work suggests that mechanical stress reduces SFRPs expression both in vivo and in vitro and promotes TMJOA via Wnt/ß-catenin signaling. Suppression of Wnt/ß-catenin signaling promotes SFRPs expression, especially SFRP3 and SFRP4 expression, and rescues mechanical stress-induced cartilage degeneration. Wnt/ß-catenin signaling and SFRPs may represent potential therapeutic targets for TMJOA.

Abnormal eruption of teeth in relation to FGFR1 heterozygote mutation: a rare case of osteoglophonic dysplasia with 4-year follow-up.

BACKGROUND: We report a case and its 4-year follow-up of Osteoglophonic dysplasia (OD), a rare disease that disturbs both skeletal and dental development, which is usually caused by heterozygous FGFR1 mutations. CASE PRESENTATION: This article presents a case where a 6-year-old male patient suffered dysregulation of tooth eruption and was diagnosed with osteogenic dysplasia from a fibroblast growth factor receptor 1 (FGFR1) heterozygote mutation. However, the number of teeth is within the normal range, and their roots are well developed. Several interventions were implemented with varying degrees of results. The details of the 4-year follow-up showed that the signs of OD were more pronounced, including dwarfism, frontal bossing, delayed skeletal maturation, anteverted nares, micrognathia, and prominent ears, but the patient's impacted teeth and edentulous jaws remained unchanged. CONCLUSIONS: FGFR1 heterozygote mutation and OD present significant difficulty for teeth eruption and subsequent intervention. Further measures ought to be taken in recognizing various symptoms presented by the patient. This case supports the significance of careful inquiry, comprehensive physical examination and correct diagnosis as indispensable steps for clinical practice in patients with unerupted teeth. Additionally, the detailed case and its 4-year follow-up length may provide new insights into osteogenic dysplasia and patients with impacted teeth while encouraging further exploration in treatment methods.

Experimental functional shift-induced osteoarthritis-like changes at the TMJ and altered integrin expression in a rat model.

Mandibular deviation affects the biomechanical environment of the temporomandibular joint (TMJ) and causes thinning of cartilage on the deviated side. We aimed to evaluate, using a rat model, the effect of mandibular functional deviation on the TMJ in relation to the functional roles of integrin ß family members. The effects of experimental functional deviation on the TMJ of 6-week-old Sprague-Dawley female rats, randomly assigned to control (n = 42) and experimental groups (n = 42), were evaluated at 3 days and 1, 2, 4, and 8 weeks by histological staining, immunofluorescence, real-time quantitative polymerase chain reaction, and micro-computed tomography. The results showed that the experimental functional shift changed the shape of condyles, thinned the cartilage, and increased the proportion of the hypertrophic layer on the deviated sides of condyles. In addition, the extracellular matrix of the condyle cartilage exhibited degradation at 1 week and subchondral trabecular bone was lost at 4 and 8 weeks. Osteoarthritis (OA)-like changes occurred in the left and right condyles of rats in the experimental group and were aggravated over time. Integrin ß family expression, especially integrin ß2 , was altered from week 1, possibly related to the OA-like changes. These data may provide insight into the onset of TMJ OA.

Bull's eye or typhoon eye? Psychological distress and associated factors in Wuhan and surrounding areas during the COVID-19 pandemic.

The COVID-19 pandemic caused significant psychological consequences among the public, especially for people in the epicenter. This study examined the 'bull's eye' model by comparing the level of psychological distress and the effect of different stressors in Wuhan (the original epicenter) with that in the surrounding areas in Hubei Province during the pandemic. Data were obtained from a cross-national survey of 10 478 respondents between the ages of 18 and 80 years in Hubei Province during the peak of the pandemic. Results of the ordinary least squares regression models showed that Wuhan residents experienced more psychological distress than those in the surrounding areas. Social and economic problems caused by the pandemic, risk exposure, perceived discrimination, and information-seeking behaviors were positively associated with distress. Social assistance was negatively associated with distress. Findings were consistent with the bull's eye model by revealing both a higher level of psychological distress and a stronger effect of stressors among the Wuhan residents than with those in low-risk areas. Thus, policymakers and psychological workers should provide adequate psychological services in high-risk areas. Lowering risk exposure, reducing discrimination against people in the epicenter, and improving information quality are essential to alleviate their psychological distress.

Does education matter for psychological recovery amidst the COVID-19 pandemic? Evidence from a panel survey in Hubei, China.

OBJECTIVES: Little has been done to examine socioeconomic differences in the trajectory of psychological well-being during a disaster. This paper investigates educational differences in the changes in psychological well-being during the COVID-19 pandemic and explores the mechanisms of the differences. METHODS: The data were obtained from a unique two-wave panel survey conducted during the peak and waning phases of the pandemic in Hubei province, the epicenter of the pandemic in China. RESULTS: At the peak of the pandemic, individuals with different levels of education reported high and similar levels of psychological distress. As the pandemic subsided, the psychological well-being of people of all educational levels rebounded, but the recovery was greater and faster for those with tertiary education. Mediation analysis shows that neighborhood social support and evaluation of the performance of grassroots government partially explained the advantage of the more highly educated. CONCLUSION: This study reveals how social differentiation is translated into health disparities when a disaster strikes. It may also inform public policy by identifying segments of the population at heightened risk of psychological distress during the COVID-19 pandemic.

Role of neighborhood social support in stress coping and psychological wellbeing during the COVID-19 pandemic: Evidence from Hubei, China.

The COVID-19 pandemic that emerged in Wuhan, the capital city of Hubei province in China, has caused severe health problems and imposed a tremendous psychological impact on the public. This study investigated the risk and protective factors associated with psychological distress among Hubei residents during the peak of the outbreak. Data were obtained from a combined online and telephone survey of 1,682 respondents. Various COVID-19-related stressors, including risk exposure, limited medical treatment access, inadequate basic supplies, reduced income, excessive exposure to COVID-19-related information, and perceived discrimination, were associated with psychological distress. Neighborhood social support can reduce psychological distress and buffer the effect of COVID-19-related stressors, whereas support from friends/relatives affected stress coping limitedly. Interventions to reduce stressors and promote neighborhood support are vital to reduce psychological distress during infectious disease outbreaks.

Changes in psychological wellbeing, attitude and information-seeking behaviour among people at the epicentre of the COVID-19 pandemic: a panel survey of residents in Hubei province, China.

While most research focuses on the clinical treatment of COVID-19, fewer studies have investigated individuals' responses towards this novel infectious disease. This study aims to report the temporal changes in individuals' psychological wellbeing, perceived discrimination, sociopolitical perceptions and information-seeking behaviours among the general public in Hubei, China. Data were obtained from a two-wave survey of 1902 respondents aged 18-80 in Hubei province during the peak and mitigation stages of the outbreak. The results showed that the prevalence of psychological distress dropped from over 75% to around 15% throughout the study period, but perceived discrimination remained stable. Female, middle-aged, well-educated respondents and those employed in government/public institutions/state-owned enterprises tended to report more distress. While respondents' attention on COVID-19 information kept high and stable, their sources of information diversified across different sociodemographic groups. Over time, people obtained more social support from neighbourhoods than from their friends and relatives or non-government organisations. Over 80% of respondents were satisfied with the performance of the central government, which was notably higher than their ratings on the local government and neighbourhood/village committees. The findings of this research are informative for formulating effective intervention strategies to tackle various psychosocial problems during COVID-19.

Stress overload-induced periodontal remodelling coupled with changes in high mobility group protein B1 during tooth movement: an in-vivo study.

High mobility group protein B1 (HMGB1), a bone-active cytokine and an osteocyte alarmin, might have dual functions in bone metabolism that could benefit bone formation and accelerate osteoclastogenic activity. High mobility group protein B1 was recently shown to be involved in tooth movement. Here, we investigated the expression of HMGB1, which remains poorly elucidated, under stress overload-induced periodontal remodelling conditions in vivo. Thirty-six Sprague-Dawley rats (male, 180-200 g) were randomly divided into three groups: two experimental groups, in which 50 or 100 g of force was applied to the first molars for 7 d to induce movement; and one control group, in which no force was applied. These stresses induced tooth movement over significantly different distances, and marked morphological changes were consistently observed in the periodontal tissues of the experimental rats, as demonstrated by histological staining. A real-time PCR analysis showed upregulation of the receptor activator of nuclear factor-kappaB ligand-to-osteoprotegerin ratio and downregulation of the Hmgb1 gene. Changes in both location and expression of the HMGB1 were observed through immunofluorescence analysis. Our data suggest that HMGB1 expression during orthodontic tooth movement might be regulated in a time- and force-dependent manner that is substantially more complex than anticipated.

MicroRNA­210 negatively regulates the radiosensitivity of nasopharyngeal carcinoma cells.

Radiotherapy is one of the primary methods of treatment of malignant tumors, however, resistance to radiation is a major problem. The reasons for the radioresistance are still poorly understood. However, it is generally accepted that microRNAs (miRNAs or miRs) can regulate the radiosensitivity of tumors. The present study therefore aimed to identify specific miRNAs and their effects on radioresistant cells. More specifically, the aim was to investigate specific miRNAs and their effects on radioresistant tumor cells. The radioresistant tumor cells (CNE­2R) were established using a dose gradient method, and the miRNA expression profiles of CNE­2R cells and the parental cells (CNE­2) were determined. The expression of miR­210 in CNE­2R cells was significantly higher than in CNE­2 cells. CNE­2R cells were transfected with LV­hsa­miR­210­inhibitor, and CNE­2 cells were transfected with LV­hsa­miR­210. The expression of miR­210 was confirmed by reverse transcription quantitative­polymerase chain reaction. The percentages of CNE­2R­miR­210­inhibitor and CNE­2 cells in the G2/M phase were higher than in the CNE­2R and CNE­2­miR­210 cells, and the percentages of cells in S phase were lower than in the CNE­2R and CNE­2­miR­210 cells. Following 4 Gy of radiation, CNE­2R­miR­210­inhibitor and CNE­2 cells, which express low levels of miR­210, had a higher apoptosis rate than CNE­2R and CNE­2­miR­210 cells. Following 4, 8 and 12 Gy of radiation, cell viability and survival fraction of CNE­2R­miR­210­inhibitor cells were lower than those of CNE­2R and CNE­2­miR­210 cells, and similar to those of CNE­2 cells. Together, these findings strongly suggest that miR­210 negatively regulates the radiosensitivity of tumor cells, and may therefore have therapeutic potential for the treatment of radiation resistance.

Synthetic hexaploid wheat and its utilization for wheat genetic improvement in China.

Synthetic hexaploid wheat (Triticum turgidumxAegilops tauschii) was created to explore for novel genes from T. turgidum and Ae. tauschii that can be used for common wheat improvement. In the present paper, research advances on the utilization of synthetic hexaploid wheat for wheat genetic improvement in China are reviewed. Over 200 synthetic hexaploid wheat (SHW) accessions from the International Maize and Wheat Improvement Centre (CIMMYT) were introduced into China since 1995. Four cultivars derived from these, Chuanmai 38, Chuanmai 42, Chuanmai 43 and Chuanmai 47, have been released in China. Of these, Chuanmai 42, with large kernels and resistance to stripe rust, had the highest average yield (>6 t/ha) among all cultivars over two years in Sichuan provincial yield trials, outyielding the commercial check cultivar Chuanmai 107 by 22.7%. Meanwhile, by either artificial chromosome doubling via colchicine treatment or spontaneous chromosome doubling via a union of unreduced gametes (2n) from T. turgidum-Ae. tauschii hybrids, new SHW lines were produced in China. Mitotic-like meiosis might be the cytological mechanism of spontaneous chromosome doubling. SHW lines with genes for spontaneous chromosome doubling may be useful for producing new SHW-alien amphidiploids and double haploid in wheat genetic improvement.