M2 macrophages secrete glutamate-containing extracellular vesicles to alleviate osteoporosis by reshaping osteoclast precursor fate.

Osteoclast precursors (OCPs) are thought to commit to osteoclast differentiation, which is accelerated by aging-related chronic inflammation, thereby leading to osteoporosis. However, whether the fate of OCPs can be reshaped to transition into other cell lineages is unknown. Here, we showed that M2 macrophage-derived extracellular vesicles (M2-EVs) could reprogram OCPs to downregulate osteoclast-specific gene expression and convert OCPs to M2 macrophage-like lineage cells, which reshaped the fate of OCPs by delivering the molecular metabolite glutamate. Upon delivery of glutamate, glutamine metabolism in OCPs was markedly enhanced, resulting in the increased production of α-ketoglutarate (αKG), which participates in Jmjd3-dependent epigenetic reprogramming, causing M2-like macrophage differentiation. Thus, we revealed a novel transformation of OCPs into M2-like macrophages via M2-EVs-initiated metabolic reprogramming and epigenetic modification. Our findings suggest that M2-EVs can reestablish the balance between osteoclasts and M2 macrophages, alleviate the symptoms of bone loss, and constitute a new approach for bone-targeted therapy to treat osteoporosis.

Comparison of rehabilitation outcomes between robot-assisted and freehand screw placement in treatment of femoral neck fractures: a systematic review and meta-analysis.

PURPOSE: To compare the postoperative rehabilitation of femoral neck fractures treated with robot-assisted nailing and freehand nailing. METHODS: We systematically searched the PubMed, EMBASE, Cochrane, China National Knowledge Infrastructure(CNKI), WanFang database, China Science and Technology Journal Database (VIP) and Web of Science databases to identify potentially eligible articles. Indispensable data such as the year of publication, country, study type, robot type, age, number of patients, sex distribution, study design, and outcome indicators were extracted. The outcome indicators of interest included healing rate, length of healing time, Harris score, operation time, frequency of X-ray fluoroscopy, frequency of guide pin insertion, and intraoperative blood loss. RevMan 5.4.1 was used for the meta-analysis. RESULTS: Fourteen studies with 908 participants were included in this meta-analysis. The results showed that in terms of healing rate (SMD = 2.75, 95% CI, 1.03 to 7.32, P = 0.04) and Harris score (SMD = 2.27, 95% CI, 0.79 to 3.75, P = 0.003), robot-assisted screw placement technique scores were higher than the traditional freehand technique. Additionally, operative time (SMD = -12.72, 95% CI, -19.74 to -5.70, P = 0.0004), healing time (SMD = -13.63, 95% CI, -20.18 to -7.08, P < 0.0001), frequency of X-ray fluoroscopy (SMD = - 13.64, 95% CI, - 18.32 to - 8.95, P < 0.00001), frequency of guide pin insertion (SMD = - 7.95, 95% CI, - 10.13 to - 5.76, P < 0.00001), and intraoperative blood loss (SMD = - 17.33, 95% CI, - 23.66 to - 11.00, P < 0.00001) were lower for patients who underwent robotic-assisted screw placement than those for patients who underwent the conventional freehand technique. CONCLUSION: Compared to the freehand nailing technique, robot-assisted nailing helps improve postoperative healing rates in patients with femoral neck fractures; shortens healing times; better restores hip function; reduces the number of intraoperative fluoroscopies, guides pin placements; reduces intraoperative bleeding; and increases perioperative safety.

Effects of temperature on incidence of bacillary dysentery in a temperate continental arid climate city in northwest China.

The effect of ambient temperature on health continues to draw more and more attention with the global warming. Bacillary dysentery (BD) is a major global environmental health issue and affected by temperature and other environmental variables. In the current study, we evaluated the effect of temperature on the incidence of BD from January 1st, 2008 to December 31st, 2011 in Jiayuguan, a temperate continental arid climate city in the Hexi Corridor of northwest China. A distributed lag non-linear model (DLNM) was performed to evaluate the lag effect of temperature on BD up to 30 days. Results showed the risk of BD increased with temperature significantly, especially after 8 °C. The maximum risk of BD was observed at extreme high temperature (29 °C). The effect of temperature on BD risk was significantly divided into short-term effect at lag 5 days and long-term effect at lag 30 days. Age ≤ 15 years were most affected by high temperature. The maximum cumulative risk for lag 30 days (25.8, 95% CIs: 11.8-50.1) was observed at 29 °C. Age ≤ 15 years and females showed short-term effect at lag 5 days and long-term effect at lag 30 days, while age > 15 years and males showed acute short-term effect at lag 0 and light long-term effect at lag 16 days.

Design of microperforated nanofibrous membrane coated nonwoven structure for acoustic applications.

In this paper, a promising acoustic structure for noise reduction was prepared, in which microperforated nanofibrous resonant membrane together with nonwovens were used. The role of microperforated nanofibrous film, the effect of perforation parameters, cavity and the assembly sequence of the composite fibrous structure on sound absorption performance has been studied. This structure effectively combined the porous sound absorbing, micro-perforated absorbing and membrane resonance mechanisms, which can improve the sound absorbing performance without weight and thickness penalty offering a competitive advantage in noise reduction. In addition, the composite materials exhibited favorable performance in a wide-frequency regime under the condition of appropriate assembly sequence and perforation parameters.

Outcomes and risk factors of perforating and non-perforating middle cerebral artery infarctions after intravenous thrombolysis.

The clinical symptoms of perforating arteries differ, and responses to intravenous thrombolytic therapy are heterogeneous. Here, we investigated the effect of intravenous thrombolytic therapy and the related factors influencing acute perforating and non-perforating middle cerebral artery infarctions. We analyzed 320 patients with acute middle cerebral artery infarction who received alteplase thrombolysis within 4.5 h of onset at two stroke centers from January 2016 to December 2019. Outcome measures included rates of a favorable functional outcome (modified Rankin Scale scores of 0-2), distribution of modified Rankin Scale scores, intracranial hemorrhage, and symptomatic cerebral hemorrhage at 14 days, with comparisons between perforating artery and non-perforating artery cerebral infarction groups. In the perforating vessel disease group, 12 cases (17.4%) of intracranial hemorrhage occurred, with symptomatic cerebral hemorrhage in three cases (4.3%); there were no significant differences between the perforating and non-perforating vessel disease groups (all P > 0.05). In the perforating vessel disease group, the only significant prognostic factor was the National Institutes of Health Stroke Scale score before thrombolysis (Exp(B) = 1.365; 95% confidence interval [CI] 1.124-1.659; P = 0.002), and the only significant risk factor for hemorrhagic transformation was previous perforator disease (Exp(B) = 0.078; P = 0.038). Regardless of whether an acute infarction is perforating or non-perforating, intravenous thrombolytic therapy can yield a favorable outcome. Therefore, intravenous thrombolysis should be actively administered to treat perforating artery infarctions with a high risk of disability.

Short-term effect of ambient ozone pollution on respiratory diseases in western China.

Ambient air pollution has been regarded as an important cause of the morbidity and mortality of respiratory diseases. In the current work, a total of 469,490 respiratory emergency room (ER) visits in Lanzhou, China from Jan 1, 2013 to Dec 31, 2016 were collected. A generalized additive model (GAM) was used to investigate the association between O3 and respiratory ER visits for the different gender and age subgroups. The results showed that: (a) with per inter-quartile range (IQR) (31 µg/m3) increase in O3, the greatest relative risk (RR) of respiratory ER visits for the total was 1.014 (95% CI 1.008-1.020) at lag 4 days. Females and 16-to-45-year-olds were relatively more sensitive to O3; (b) the significant lag effects were found in single-day lag models, with the highest RR values for different groups were observed at lag 3-lag 5 days. The multi-day cumulative lag effects were stronger for the total; (c) in the multiple-pollutant models, the effects of O3 were generally increased when introducing other pollutants (PM10, PM2.5, SO2 and NO2) for adjustment. This study demonstrated that short-term exposure to O3 increased the RR of respiratory ER visits in Lanzhou, China.

Particulate matter pollution and emergency room visits for respiratory diseases in a valley Basin city of Northwest China.

Epidemiological studies have suggested that particulate matter (PM) pollution seriously affects human health, particularly it is closely associated with respiratory diseases. The aim of this study is to quantitatively evaluate the effect of PMs (PM10 and PM2.5) on emergency room (ER) visits for respiratory diseases in Lanzhou, a valley basin city in northwest China. Based on the data of the ER visits, daily concentration of particulate matters and daily meteorological elements from January 1, 2013, to July 31, 2017, we used a generalized additive model (GAM) of time series to evaluate the exposure-response relationship between PMs and respiratory ER visits. Seasonal modified effects of PM2.5 and PM10 on different age and gender groups were also performed. Results showed that the highest incidence of respiratory diseases occurred in winter. Respiratory ER visits for the total were significantly associated with PM2.5 (at lag 0 day) and PM10 (at lag 3 days), with relative risks (RRs) of 1.042 (95%CI: 1.036 -1.047) and 1.013 (95%CI: 1.011-1.016), respectively. Effects of PM pollutants on respiratory diseases are different among different age and gender groups. Children under 15 years and the elders over 60 years were the most sensitive to PM pollution, and males were more sensitive than females. The results obtained in the current study would provide a scientific evidence for local government to make policy decision for prevention of respiratory diseases.

Persistent pollution episodes, transport pathways, and potential sources of air pollution during the heating season of 2016-2017 in Lanzhou, China.

As one of the most important industrial cities in Northwest China, Lanzhou currently suffers from serious air pollution. This study analyzed the formation mechanism and potential source areas of persistent air pollution in Lanzhou during the heating period from November 1, 2016 to March 31, 2017 based on the air pollutant concentrations and relevant meteorological data. Our findings indicate that particulate pollution was extremely severe during the study period. The daily PM2.5 and PM10 concentrations had significantly negative correlations with daily temperature, wind speed, maximum daily boundary layer height, while the daily PM2.5 and PM10 concentrations showed significantly positive correlations with daily relative humidity. Five persistent pollution episodes were identified and classified as either stagnant accumulation or explosive growth types according to the mechanism of pollution formation and evolution. The PM2.5 and PM10 concentrations and PM2.5/PM10 ratio followed a growing "saw-tooth cycle" pattern during the stagnant accumulation type event. Dust storms caused abrupt peaks in PM10 and a sharp decrease in the PM2.5/PM10 ratio in explosive growth type events. The potential sources of PM10 were mainly distributed in the Kumtag Desert in Xinjiang Uygur Autonomous Region, the Qaidam Basin and Hehuang Valley in Qinghai Province, and the western and eastern Hexi Corridor in Gansu Province. The contributions to PM10 were more than 120 µg/m3. The important potential sources of PM2.5 were located in Hehuang Valley in Qinghai and Linxia Hui Autonomous Prefecture in Gansu; the concentrations of PM2.5 were more than 60 µg/m3.

Cardamonin induces G2/M arrest and apoptosis via activation of the JNK-FOXO3a pathway in breast cancer cells.

Cardamonin (CD), a naturally occurring chalcone isolated from large black cardamom, was previously reported to suppress the proliferation of breast cancer cells. However, its precise molecular anti-tumor mechanisms have not been well elucidated. In this study, we found that CD markedly inhibited the proliferation of MDA-MB 231 and MCF-7 breast cancer cells through the induction of G2/M arrest and apoptosis. Reactive oxygen species (ROS) plays a pivotal role in the inhibition of CD-induced cell proliferation. Treatment with N-acetyl-cysteine (NAC), an ROS scavenger, blocked CD-induced G2/M arrest and apoptosis in this study. Quenching of ROS by overexpression of catalase also blocked CD-induced cell cycle arrest and apoptosis. We showed that CD enhanced the expression and nuclear translocation of Forkhead box O3 (FOXO3a) via upstream c-Jun N-terminal kinase, inducing the expression of FOXO3a and its target genes, including p21, p27, and Bim. This process led to the reduction of cyclin D1 and enhancement of activated caspase-3 expression. The addition of NAC markedly reversed these effects, knockdown of FOXO3a using small interfering RNA also decreased CD-induced G2/M arrest and apoptosis. In vivo, CD efficiently suppressed the growth of MDA-MB 231 breast cancer xenograft tumors. Taken together, our data provide a molecular mechanistic rationale for CD-induced cell cycle arrest and apoptosis in breast cancer cells.

A Quadrupole-Central-Transition 59 Co NMR Study of Cobalamins in Solution.

We report the first observation of quadrupole-central-transition (QCT) 59 Co (I=7/2) NMR signals from three cobalamin (Cbl) compounds (CNCbl, MeCbl, and AdoCbl) dissolved in glycerol/water. Measurements were performed at four magnetic fields ranging from 11.7 to 21.1 T. We found that the 59 Co QCT signals observed for cobalamin compounds in the slow motion regime (ω0 τC ≫1) are significantly narrower than those observed from their aqueous solutions where the molecular tumbling is near the condition of ω0 τC ≈1. We demonstrated that an analysis of 59 Co QCT signals recorded over different temperatures and at multiple magnetic fields allowed determination of both the 59 Co quadrupole coupling constant and chemical shift anisotropy for each of the three cobalamins. We successfully applied the 59 Co QCT NMR approach to monitor in situ the transformation of CNCbl to its "base off" form in the presence of KCN. We further discovered that, to obtain the maximum QCT signal intensity with the Hahn-echo sequence, a strong B1 field should be used for the first 90°â€…pulse, but a weak B1 field for the second 180°â€…pulse. The reported 59 Co QCT NMR methodology opens up a new direction for studying structure and function of cobalamin compounds and their roles in biological processes.

Sensing Properties of Fused Silica Single-Mode Optical Fibers Based on PPP-BOTDA in High-Temperature Fields.

The strain of fiber-reinforced polymer (FRP) bars at high temperatures is currently difficult to measure. To overcome this difficulty, a method of smart FRP bars embedded with optical fibers was proposed and studied, in which an ordinary single-mode optical fiber was applied as a distributed sensor. In this paper, both the distributed temperature and strain-sensing characteristics of optical fiber were studied based on pulse pre-pump Brillouin optical time-domain analysis (PPP-BOTDA) under high temperature. The temperature and strain coefficients were investigated under a thermomechanical coupling environment with consideration of large strain levels. The experimental results show that the temperature and strain coefficients decreased as the temperature increased, because the properties of silica and coating materials changed with temperature. Then, the formulas for determining the temperature and strain coefficients at high temperatures were introduced and discussed. The excellent sensing performance of the optical fiber indicated that smart FRP bars have the potential for use at high temperatures.

Reorganization of functional brain networks mediates the improvement of cognitive performance following real-time neurofeedback training of working memory.

Working memory (WM) is essential for individuals' cognitive functions. Neuroimaging studies indicated that WM fundamentally relied on a frontoparietal working memory network (WMN) and a cinguloparietal default mode network (DMN). Behavioral training studies demonstrated that the two networks can be modulated by WM training. Different from the behavioral training, our recent study used a real-time functional MRI (rtfMRI)-based neurofeedback method to conduct WM training, demonstrating that WM performance can be significantly improved after successfully upregulating the activity of the target region of interest (ROI) in the left dorsolateral prefrontal cortex (Zhang et al., [2013]: PloS One 8:e73735); however, the neural substrate of rtfMRI-based WM training remains unclear. In this work, we assessed the intranetwork and internetwork connectivity changes of WMN and DMN during the training, and their correlations with the change of brain activity in the target ROI as well as with the improvement of post-training behavior. Our analysis revealed an "ROI-network-behavior" correlation relationship underlying the rtfMRI training. Further mediation analysis indicated that the reorganization of functional brain networks mediated the effect of self-regulation of the target brain activity on the improvement of cognitive performance following the neurofeedback training. The results of this study enhance our understanding of the neural basis of real-time neurofeedback and suggest a new direction to improve WM performance by regulating the functional connectivity in the WM related networks.

Association study of common variations of FBN1 gene and essential hypertension in Han Chinese population.

Fibrillin-1 (FBN1) was reported to have impact on the physiological arterial stiffness and vascular remodeling with hypertension of recent years. In the previous study we reported the association of four functional single nucleotide polymorphisms (SNPs) of FBN1 gene and hypertension. Here, we further investigate the association of four tagging SNPs (tagSNPs) which covered remain genetic variation blocks of FBN1 gene with hypertension, blood pressure and efficacy of antihypertensive in a South Han Chinese population. A case-control study including 2,012 hypertension cases and 2,116 controls age- and sex-matched controls was conducted from a community-based population and four candidate tagSNPs of the FBN1 gene were genotyped. Association analysis by multiple logistic regression was conducted for allele, genotype and haplotype and hypertension, blood pressure trait and control status with antihypertensive. General linear model was applied to compare blood pressure levels between genotypes. The association of rs17361868 and hypertension was statistically significant and that was further observed in female, ≥55 years, non-smoking and non-drinking populations (P < 0.05). Significant association of rs668842, rs11635140 and hypertension were observed in <55 years population as well as the later in female and non-smoking populations respectively. Haplotype G-T constructed of rs668842 and rs11635140 was significantly associated with hypertension comparing to reference haplotype A-C (P = 0.022). Normally distributed square root of TGF-ß1 (pg/ml) of hypertension cases (148.56 ± 66.46) was significantly higher than that of control (128.52 ± 65.11), P = 0.008. Furthermore, TGF-ß1 was significantly correlated with SBP (r = 0.135, P = 0.018) and DBP (r = 0.154, P = 0.007) respectively whereas no statistical difference of blood pressure or TGF-ß1 was observed between genotypes. Remarkably, rs17361868 were significantly associated with the status of blood pressure in the patients taking three of the antihypertensive drugs, Zhen Ju Jiang Ya tablets, Jiang Ya tablet and compound reserpine (P < 0.05). The present study provides further association evidence of FBN1 gene polymorphisms and hypertension, antihypertensive efficacy. Further replication of these results via association or prospective studies conducted in other populations is warranted.

Mechanism Analysis for the Enhancement of Low-Temperature Impact Toughness of Nodular Cast Iron by Heat Treatment.

The low-temperature impact toughness of nodular cast iron can be significantly enhanced by heat treatment, and thus meet the severe service requirements in the fields of high-speed rail and power generation, etc. In order to explore the enhancement mechanism, microstructure, hardness, composition and other characteristics of as-cast and heat-treated nodular cast iron is systematically tested and compared by optical microscopy, microhardness tester, EBSD, SEM, electron probe, and impact toughness testing machine in this study. The results show that heat treatment has little effect on the morphology and size of graphite in nodular cast iron, ignores the effect on the grain size, morphology, and distribution of ferritic matrix, and has little effect on the hardness and exchange of elements, while it is meaningful to find that heat treatment brings about significant decrease in high-angle grain boundaries (HAGB) between 59° and 60°, decreasing from 10% to 3%. Therefore, the significant enhancement of low-temperature impact toughness of nodular cast iron by heat treatment may result from the obvious decrease in HAGB between 59° and 60°, instead of other reasons. From this perspective, the study can provide novel ideas for optimizing the heat treatment process of nodular cast iron.

Multi-objective pedestrian tracking method based on YOLOv8 and improved DeepSORT.

A multi-objective pedestrian tracking method based on you only look once-v8 (YOLOv8) and the improved simple online and real time tracking with a deep association metric (DeepSORT) was proposed with the purpose of coping with the issues of local occlusion and ID dynamic transformation that frequently arise when tracking target pedestrians in real complex traffic scenarios. To begin with, in order to enhance the feature extraction network's capacity to learn target feature information in busy traffic situations, the detector implemented the YOLOv8 method with a high level of small-scale feature expression. In addition, the omni-scale network (OSNet) feature extraction network was then put on top of DeepSORT in order to accomplish real-time synchronized target tracking. This increases the effectiveness of picture edge recognition by dynamically fusing the collected feature information at various scales. Furthermore, a new adaptive forgetting smoothing Kalman filtering algorithm (FSA) was created to adapt to the nonlinear condition of the pedestrian trajectory in the traffic scene in order to address the issue of poor prediction attributed to the linear state equation of Kalman filtering once more. Afterward, the original intersection over union (IOU) association matching algorithm of DeepSORT was replaced by the complete-intersection over union (CIOU) association matching algorithm to fundamentally reduce the target pedestrians' omission and misdetection situation and to improve the accuracy of data matching. Eventually, the generalized trajectory feature extractor model (GFModel) was developed to tightly merge the local and global information through the average pooling operation in order to get precise tracking results and further decrease the impact of numerous disturbances on target tracking. The fusion algorithm of YOLOv8 and improved DeepSORT method based on OSNet, FSA and GFModel was named YOFGD. According to the experimental findings, YOFGD's ultimate accuracy can reach 77.9% and its speed can reach 55.8 frames per second (FPS), which is more than enough to fulfill the demands of real-world scenarios.

Facial age recognition based on deep manifold learning.

Facial age recognition has been widely used in real-world applications. Most of current facial age recognition methods use deep learning to extract facial features to identify age. However, due to the high dimension features of faces, deep learning methods might extract a lot of redundant features, which is not beneficial for facial age recognition. To improve facial age recognition effectively, this paper proposed the deep manifold learning (DML), a combination of deep learning and manifold learning. In DML, deep learning was used to extract high-dimensional facial features, and manifold learning selected age-related features from these high-dimensional facial features for facial age recognition. Finally, we validated the DML on Multivariate Observations of Reactions and Physical Health (MORPH) and Face and Gesture Recognition Network (FG-NET) datasets. The results indicated that the mean absolute error (MAE) of MORPH is 1.60 and that of FG-NET is 2.48. Moreover, compared with the state of the art facial age recognition methods, the accuracy of DML has been greatly improved.

Highly stretchable polyvinyl alcohol composite conductive hydrogel sensors reinforced by cellulose nanofibrils and liquid metal for information transmission.

Conductive hydrogels have received widespread attention in the field of flexible sensors. However, a single network structure inside the hydrogel sensor usually makes it difficult to bear larger mechanical loadings, greatly limiting practical applications. Developing a recoverable conductive hydrogel sensor with high toughness and adaptability is still challenging. Herein, a high-performance polyvinyl alcohol (PVA)-based conductive composite hydrogel was constructed, assisted by green cellulose nanofibrils (CNFs), magnesium chloride (MgCl2), ethylene glycol (EG), and liquid metal (LM). The synergistic effects between CNFs and LM enhanced the network structure inside the recoverable hydrogel. This resulted in an excellent tensile strength of 3.86 MPa with an elongation at break of as high as 918.4 % and compressive strength of 4.04 MPa at 80 % strain. In addition, the conductive network composed of MgCl2 and LM endowed the hydrogel good electrical conductivity. Moreover, it could be used as a flexible strain sensor for various application scenarios, e.g., micro-stress monitoring (water droplet falling) and information encryption transmission of Morse code. Such uniqueness will provide a design strategy for developing a new generation of hydrogel sensors.

Gas explosion characteristics and spray control mechanism in underground square.

The spray system mechanism during a gas explosion in an underground square pipeline is complex. In this paper, the underground square of Fuxin City is selected as the research object. FLACS numerical simulation software is used to analyze the spatial and temporal distribution characteristics of a gas explosion in an underground square pipeline with an unopened spray system using combustion and combustion rate models. Different spray pressures were compared and analyzed to determine the optimal spray control pressure, and the spray system mechanism was clarified. The results revealed that the gas explosion overpressure is divided into the overpressure gentle, overpressure rising, and overpressure decay stages, corresponding to a trend of rapid growth and slow decline. The influence of spray pressure on the gas explosion exhibits a promotion-inhibition-promotion trend, corresponding to 0-0.2 MPa, 0.2-0.6 MPa, and 0.6-1.6 Mpa, respectively. The peak overpressure and overpressure propagation rates are the lowest at 0.6 MPa, and the explosion suppression effect is the most pronounced. The spray system mechanism varies with the explosion overpressure stages. Generally, the time to peak value, that is, the peak time, the overall duration of the explosion, and the duration of the explosion stage decrease, whereas the peak explosion overpressure decreases.

Skeleton-derived extracellular vesicles in bone and whole-body aging: From mechanisms to potential applications.

The skeleton serves as a supportive and protective organ for the body. As individuals age, their bone tissue undergoes structural, cellular, and molecular changes, including the accumulation of senescent cells. Extracellular vesicles (EVs) play a crucial role in aging through the cellular secretome and have been found to induce or accelerate age-related dysfunction in bones and to contribute further via the circulatory system to the aging of phenotypes of other bodily systems. However, the extent of these effects and their underlying mechanisms remain unclear. Therefore, this paper attempts to give an overview of the current understanding of age-related alteration in EVs derived from bones. The role of EVs in mediating communications among bone-related cells and other body parts is discussed, and the significance of bones in the whole-body aging process is highlighted. Ultimately, it is hoped that gaining a clearer understanding of the relationship between EVs and aging mechanisms may serve as a basis for new treatment strategies for age-related degenerative diseases in the skeleton and other systems.

Influential Signs of Dry Eye-Related Ocular Symptoms in Participants With Unstable Tear Film.

PURPOSE: The aim of this study was to investigate the factors influencing dry eye disease (DED)-related ocular symptoms in participants with short fluorescein tear break-up time (FTBUT). METHODS: This cross-sectional study included 82 participants with short FTBUT (<10 seconds). Examinations included Ocular Surface Disease Index (OSDI), FTBUT, average noninvasive tear break-up time (NIBUTave), lid wiper epitheliopathy, lipid layer thickness, blink rate, partial blink, tear meniscus height, and meibomian gland (MG) evaluation which included ratio of residual MG area (RMGA) and MG grade in tarsal plates. One-way analysis of variance was used to detect differences between symptomatic tear film instability group (FTBUT <5 s, OSDI ≥13), asymptomatic tear film instability group (FTBUT <5 s, OSDI <13), and control group (FTBUT ≥5 s, OSDI <13). A bivariate correlation, partial correlation, and multiple linear regression analyses were used to identify major factors. Only the right eye was included. RESULTS: Among the participants with FTBUT <5 seconds, symptomatic group showed less upper RMGA ( P < 0.001) and NIBUTave ( P = 0.010). OSDI was negatively associated with upper RMGA ( r = -0.450, P < 0.001) and NIBUTave ( r = -0.414, P = 0.001), and positively associated with upper MG grade ( r = 0.277, P = 0.027). Linear regression analysis showed that the upper RMGA significantly affected OSDI (B = -41.895, P = 0.001), while not significantly correlated with age, upper MG grade, and NIBUTave. CONCLUSIONS: The upper RMGA might be the main factor affecting DED-related discomfort in participants with unstable tear film, indicating an early ocular change in DED.