Causal associations between sleep traits and temporomandibular disorders: a bidirectional mendelian randomization analysis.

Objectives: This study aims to investigate the relationship between five sleep traits (insomnia, sleep duration, getting up in morning, snoring, and daytime nap) and temporomandibular disorders (TMD) using bi-directional Mendelian randomization. Methods: The bi-directional Mendelian randomization study was conducted in two stages. Initially, sleep traits were examined as exposures while TMD was evaluated as an outcome, whereas the second step was reversed. The inverse variance weighted (IVW) method and other Mendelian randomization methods were used for analysis. Furthermore, we performed the MR-Egger intercept, MR-PRESSO, Cochran's Q test, and "Leave-one-out" to assess the levels of pleiotropy and heterogeneity. Results: The IVW method indicates that getting up in the morning reduces the risk of developing TMD (OR = 0.50, 95% CI 0.30-0.81, p = 0.005), while insomnia may increase the risk of TMD (OR = 2.05, 95% CI 1.10-3.85, p = 0.025). However, other sleep traits are not associated with the risk of TMD, and having TMD does not alter an individual's sleep traits. After removing outliers, the results remained robust, with no pleiotropy detected. Conclusion: Genetically determined difficulty in getting up in the morning and insomnia can increase the risk of TMD. By optimizing sleep, the risk of developing TMD can be reduced. This underscores the importance of sleep in preventing TMD.

The association between weight-adjusted-waist index and muscle strength in adults: a population-based study.

Background: The relationship between the weight-adjusted-waist index (WWI) and grip strength, a crucial marker in assessing sarcopenia, lacks clarity. We aimed to explore the relationship between WWI and muscle strength across genders. Methods: The cross-sectional study involved adults with complete data on WWI and grip strength from the 2011-2014 National Health and Nutrition Examination Survey. WWI was derived by dividing waist circumference by the square root of weight. Weighted multivariable logistic regression and smooth curve fitting techniques were used to examine the independent association and potential non-linear relationship between WWI and grip strength. A two-piecewise linear regression model was utilized to determine the threshold effect. Additionally, subgroup analyses and interaction tests were conducted. Results: The study encompassed 9,365 participants, including 4,661 males and 4,704 females. Multivariate logistic regression analysis revealed a negative correlation between WWI and grip strength among males (ß = -11.49, 95% CI: -12.38, -10.60, p < 0.001) as well as females (ß = -2.53, 95% CI: -2.98, -2.08, p < 0.001). Subgroup analysis showed that the negative correlation of WWI with grip strength remained consistent across various age groups and levels of obesity for both males and females. Conclusion: An increase in WWI correlates with reduced muscle strength in both males and females. WWI was negatively associated not only with muscle mass but also with muscle strength. WWI may serve as an assessment tool for sarcopenia, but further large-scale studies are needed to clarify causality.

Association between weight-adjusted waist index and periodontitis: A population-based study.

OBJECTIVE: This study aims to examine the association between the Weight-adjusted Waist Circumference Index (WWI) and the prevalence of periodontitis, providing novel evidence on the link between central obesity and periodontal health. METHODS: A cross-sectional study was conducted with 10,289 participants enrolled from NHANES 2009 to 2014. WWI was calculated by dividing waist circumference by the square root of weight. We employed a multivariate logistic regression model and smoothed curve fitting method to evaluate the relationship between WWI and periodontitis. We also compared different subgroups and analyzed the interaction effects. RESULTS: A significant positive association between WWI and periodontitis was observed in 10,289 participants aged ≥30 (OR: 1.20, 95% CI: 1.12-1.28). Upon categorizing WWI into quartiles, the top quartile group exhibited a 27% increased prevalence of periodontitis compared to the bottom quartile (OR: 1.27, 95% CI: 1.10-1.46; P for trend = 0.001). Among individuals aged 30 to 60, the strength of this positive correlation is more pronounced than in those aged 60 and above. CONCLUSIONS: WWI demonstrates a positive correlation with periodontitis with a particularly pronounced impact on moderate periodontitis, suggesting its potential to improve periodontitis prevention in a broad population.

The association between weight-adjusted-waist index and sarcopenia in adults: a population-based study.

This study aims to investigate the relationship between weight-adjusted-waist index (WWI), a new body index, and sarcopenia, while also assessing the potential of WWI as a tool for screening sarcopenic patients. The cross-sectional study involved adults who possessed complete data on WWI and appendicular skeletal muscle mass from the 1999-2006 and 2011-2018 National Health and Nutrition Examination Surveys. Weighted multivariate regression and logistic regression analyses were employed to explore the independent relationship between WWI and sarcopenia. The study included 26,782 participants. The results showed that WWI demonstrated a positive correlation with sarcopenia risk. In the fully adjusted model, with each 1 unit increase in WWI, the risk of developing sarcopenia rose 14.55 times higher among males (OR: 14.55, 95% CI 12.33, 17.15) and 2.86 times higher among females (OR: 2.86, 95% CI 2.59, 3.15). The optimal cutoff values of WWI for sarcopenia were 11.26 cm/√kg for males and 11.39 cm/√kg for females. Individuals with a higher WWI have an increased risk of developing sarcopenia, and a high WWI functions as a risk factor for sarcopenia. Assessing WWI could assist in identifying individuals at risk of sarcopenia.

Microscopy imaging and modeling study on the mechanical properties of the primary flight feather shaft of the bean goose, Anser fabalis.

Avian flight feathers have the unique advantages of lightweight and high strength, which play a key role in their flight capacity. In this article, the rachis of the bean goose's primary flight feather was used as the research object. Its compressive properties were analyzed and the 3D microscale was observed by 3D microscope system with a super wide depth of field. The distribution of mechanical properties, section variation of fiber and internal microstructure of rachis were obtained by micro-CT technique. Based on these results, a 3D reconstructed model was established for structure mechanical simulation. The simulation results were close basically to the compressive strength of the actual sample. These results show that the synergistic effect of cortex and medulla can improve mechanical resistance of the rachis. Therefore, the best position (N3) of the primary flight feather shaft can be applied to the bionic design of thin wall structures for energy absorption. This research can provide some guidance for the application of lightweight structural design. RESEARCH HIGHLIGHTS: The internal structure of bean goose feather shaft was observed by micro-CT. The experimental method has a deeper understanding of the compressive properties of rachis fiber orientation. Under the synergistic effect of cortex and medulla, the compressive performance of rachis is better.

Identification of hub genes specific to pulmonary metastasis in osteosarcoma through integrated bioinformatics analysis.

BACKGROUND: Pulmonary metastasis is the most frequent cause of death in osteosarcoma (OS) patients. Recently, several bioinformatics studies specific to pulmonary metastatic osteosarcoma (PMOS) have been applied to identify genetic alterations. However, the interpretation and reliability of the results obtained were limited for the independent database analysis. OBJECTIVE: The expression profiles and key pathways specific to PMOS remain to be comprehensively explored. Therefore, in our study, three original datasets of GEO database were selected. METHODS: Initially, three microarray datasets (GSE14359, GSE14827, and GSE85537) were downloaded from the GEO database. Differentially expressed genes (DEGs) between PMOS and nonmetastatic osteosarcoma (NMOS) were identified and mined using DAVID. Subsequently, GO and KEGG pathway analyses were carried out for DEGs. Corresponding PPI network of DEGs was constructed based on the data collected from STRING datasets. The network was visualized with Cytoscape software, and ten hub genes were selected from the network. Finally, survival analysis of these hub genes also used the TARGET database. RESULTS: In total, 569 upregulated and 1238 downregulated genes were filtered as DEGs between PMOS and NMOS. Based on the GO analysis result, these DEGs were significantly enriched in the anatomical structure development, extracellular matrix, biological adhesion, and cell adhesion terms. Based on the KEGG pathway analysis result, these DEGs were mainly enriched in the pathways in cancer, PI3K-Akt signaling, MAPK signaling, focal adhesion, cytokine-cytokine receptor interaction, and IL-17 signaling. Hub genes (ANXA1 and CXCL12) were significantly associated with overall survival time in OS patient. CONCLUSION: Our results may provide new insight into pulmonary metastasis of OS. However, experimental studies remain necessary to elucidate the biological function and mechanism underlying PMOS.

Mechanical properties and failure deformation mechanisms of yak horn under quasi-static compression and dynamic impact.

In the natural environment, the horns of yak possess remarkable structural mechanical properties to protect the head from injury. In this paper, quasi-static compression and dynamic impact tests were conducted on yak horn in different regions under axial and lateral conditions to evaluate mechanical properties such as elastic modulus, ultimate strength and energy absorption. Meanwhile, the failure deformation mechanism under both low and high strain rates is explored. Moreover, experimental analysis of the correlation among mechanical properties, sampling position, strain rate and loading direction was conducted. Fracture surface of horn was observed with the scanning electron microscope (SEM). Research data demonstrate that specific energy absorption and mechanical properties are correlated with sampling position. Under quasi-static compression and dynamic impact, clear anisotropy behavior of horn was observed, which is evidently reflected in the load-displacement curve. Mechanical properties such as elastic modulus and ultimate strength are different under quasi-static compression and dynamic impact. The failure mode of lamellar buckling and delamination existed in the axial failure process. Brittle fracture and extrusion densification occurred more frequently in the process of lateral failure.

Microstructure and compression resistance of bean goose (Anser fabalis) feather shaft.

The bean goose Anser fabalis, noted for its excellent flying ability, has feathers composed of keratinized products derived from epidermal cells, which play a crucial role in flight. The feather shaft is an important connective unit, made of a lightweight material, which also contributes to aiding flight. The shaft can withstand loads from different directions and has outstanding compression resistance. In this study, the microstructure and composition of the A. fabalis feather shaft were observed by scanning electron microscopy and Fourier transform infrared spectrometry, and its compression resistance was studied by compression testing. The results indicated that the mechanical property of the shaft is related to its microstructure. Compression testing verified that the primary feathers had the strongest mechanical properties, followed by the secondaries, and finally the alulae. Under the same conditions, the specific energy absorption of the three feather types was 5.96, 5.02, and 3.17 J/g, respectively. With increasing moisture content, the rachis was softened and the energy absorption was reduced. At low moisture content, the specific energy absorption of the primaries was reduced to 1.03 J/g, that of the secondaries was reduced to 1.72 J/g, and that of the alulae to 0.39 J/g. The feather shafts have the advantage of light weight while maintaining the required mechanical properties. These results provide a theoretical and experimental basis for crashworthiness in bionic designs based on the requirements of light weight.

An engineering perspective on the microstructure and compression properties of the seagull Larus argentatus feather rachis.

The feathers of the seagull Larus argentatus are lightweight but can withstand high alternating stresses and exhibit excellent stiffness and strength. The shaft is an important part of the feather, with the functions of body protection and supporting flight. In this study, the microstructure properties of L. argentatus feather rachis were analysed by scanning electron microscopy (SEM). These analysis methods enabled the configuration, structure and compression properties of the rachis to be investigated. The results indicated that the rachis was composed of the outer cortex and the inner medulla. The cortex had a continuous layered nano-fibre composite structure, which bears, transmits, absorbs and disperses the compression force. The medulla had bubble-like cells with a porous-fibre structure, which rapidly absorbs, transmits and consumes compression force and is a suitably lightweight material for flight. Axial compression tests showed that the rachis from primary feathers had the best energy absorption and that from secondary feathers had the best compressive strength. The compressive strength might have something to do with the ratio of cortical area to medullary area. When the moisture content in the rachis increased, the compressive strength of feather rachis in different parts would decrease. These results indicate that the L. argentatus feather rachis have excellent compression resistance properties, deriving from structural factor.

Protective and prophylactic effects of chlorogenic acid on aluminum-induced acute hepatotoxicity and hematotoxicity in mice.

The possible health impact of the exposures to Al from environment would be inevitable for humans. Using chelating agents and natural antioxidants against Al-induced biotoxicity become a natural and modern way to prevent the adverse effects of Al in people. This study was undertaken to determine the effectiveness of chlorogenic acid (CGA, 5-O-caffeoylquinic acid) in preventing aluminum chloride (AlCl3) induced hepatotoxicity and hematotoxicity in mice. Control, Al-treated (a single injection of 25 mg Al3+/kg, i.p.), Al + CGA (2 h after, a single dose of 100 mg/kg, i.p.), CGA + Al (administered to mice daily for 5 days at 30 mg/kg before Al-treatment) and group of CGA per se (administered to mice daily for 5 days at 30 mg/kg) were used. The levels of Al in liver and blood, the activities of transaminases in serum and osmotic fragility were increased by comparison with the control, while the activities of superoxide dismutase and catalase decreased significantly in the Al-treated group. However, treating mice with CGA at either dosing regimens, post- or pre- Al administration alleviate Al oxidative damaging effects, stabilize cell membrane, prevent hepatocyte apoptosis. CGA supplementation may be favorable to avoid Al-induced hematotoxicity and hepatotoxicity for humans.