Extracellular vesicles: Their emerging roles in the pathogenesis of respiratory diseases

Alveoli are the basic structure of the lungs, consisting of various types of parenchymal and bone marrow-derived cells including alveolar macrophages. These various types of cells have several important functions; thus, communication between these cells plays an important role in homeostasis as well as in the pathophysiology of diseases in the lungs. For a better understanding of the pathophysiology of lung diseases, researchers have isolated each type of lung cell to investigate the changes in their gene expressions, including their humoral factor or adhesion molecules, to reveal the intercellular communication among these cells. In particular, investigations during the past decade have focused on extracellular vesicles, which are lipid bilayer delimited vesicles released from a cell that can move among various cells and transfer substances, including microRNAs, mRNAs and proteins, thus, functioning as intercellular messengers. Extracellular vesicles can be classified into three general groups: apoptotic bodies, exosomes, and microparticles. Extracellular vesicles, especially exosomes and microparticles, are attracting increasing attention from pulmonologists as tools for understanding pathogenesis and disease diagnosis. Here, we review studies, including our own, on exosomes and microparticles and their roles in both lung homeostasis and the pathogenesis of lung diseases such as idiopathic pulmonary fibrosis, chronic obstructive lung diseases, and acute respiratory distress syndrome. This review also addresses the roles of extracellular vesicles in COVID-19, the current global public health crisis.     

Synthetic MRI is not yet ready for morphologic and functional assessment of patellar cartilage at 1.5 Tesla

PurposeThe purpose of this study was to compare morphologic assessment and relaxometry of patellar hyaline cartilage between conventional sequences (fast spin-echo [FSE] T2-weighted fat-saturated and T2-mapping) and synthetic T2 short-TI inversion recovery (STIR) and T2 maps at 1.5 T magnetic resonance imaging (MRI).MethodThe MRI examinations of the knee obtained at 1.5 T in 49 consecutive patients were retrospectively studied. There were 21 men and 28 women with a mean age of 45 ± 17.7 (SD) years (range: 18–88 years). Conventional and synthetic acquisitions were performed, including T2-weighted fat-saturated and T2-mapping sequences. Two radiologists independently compared patellar cartilage T2-relaxation time on conventional T2-mapping and synthetic T2-mapping images. A third radiologist evaluated the patellar cartilage morphology on conventional and synthetic T2-weighted images. The presence of artifacts was also assessed. Interobserver agreement for quantitative variables was assessed using intraclass correlation coefficient (ICC).ResultsIn vitro, conventional and synthetic T2 maps yielded similar mean T2 values 58.5 ± 2.3 (SD) ms and 58.8 ± 2.6 (SD) ms, respectively (P = 0.414) and 6% lower than the expected experimental values (P = 0.038). Synthetic images allowed for a 15% reduction in examination time compared to conventional images. On conventional sequences, patellar chondropathy was identified in 35 patients (35/49; 71%) with a mean chondropathy grade of 4.8 ± 4.8 (SD). On synthetic images, 28 patients (28/49; 57%) were diagnosed with patellar chondropathy, with a significant 14% difference (P = 0.009) and lower chondropathy scores (3.7 ± 4.9 [SD]) compared to conventional images. Motion artifacts were more frequently observed on synthetic images (18%) than on conventional ones (6%). The interobserver agreement was excellent for both conventional and synthetic T2 maps (ICC > 0.83). Mean cartilage T2 values were significantly greater on synthetic images (36.2 ± 3.8 [SD] ms; range: 29-46 ms) relative to conventional T2 maps (31.8 ± 4.1 [SD] ms; range: 26-49 ms) (P < 0.0001).ConclusionDespite a decrease in examination duration, synthetic images convey lower diagnostic performance for chondropathy, greater prevalence of motion artifacts, and an overestimation of T2 values compared to conventional MRI sequences.     

There is a difference in functional ankle stability between different types of footwear in male athletes: A cross-sectional study

ContextLateral ankle sprains (LAS) are among the most common injuries in sports, with a poor long – term prognosis due to high chronicity and recurrence rates. Chronic ankle instability (CAI) results up to 40% of people that endured a first – time LAS.ObjectiveThe aim of this study was to compare ankle stability between groups characterised by the use of different types of footwear during their sport activities.DesignCross-sectional study.SettingFirm training surface, local sport clubs.ParticipantsFifty - one male subjects were recruited, distributed in four groups based on the type of footwear they use during their sport activities.Main outcome measuresAll subjects performed four clinical ankle stability tests, and completed the Dutch version of the Cumberland Ankle Instability Tool (CAIT) and Profile of Mood States (POMS). All clinical ankle stability tests were performed barefoot.ResultsSubjects performing their sport activities barefoot scored better than subjects performing their sport with shoes at the multiple hop test (p = .002 to .047) and executed the figure–of–8 hop test significantly faster than subjects with submalleolar ankle support (AS) (p = .019). Subjects with submalleolar AS and studs showed significantly better results than subjects with supramalleolar AS on the CAIT– score (p = .024, p = .030) and the side– hop test (p = .050, p = .045). They also scored significantly better than subjects with submalleolar AS for the side – hop test (p = .032), foot – lift test (p = .019) and figure–of 8 hop test (p = .011).ConclusionBarefoot sports performing subjects appear to have better ankle stability compared to subjects performing their sports with shoe support. Subjects performing sports with high AS appear to have worst ankle stability.Level of evidence: Level III, Cross–sectional study.     

Mortality prediction in chronic obstructive pulmonary disease and obstructive sleep apnea

BackgroundWe aimed to assess mortality in chronic obstructive pulmonary disease (COPD), obstructive sleep apnea (OSA), and overlap syndrome, and evaluate which polysomnographic indices—apnea-hypopnea index (AHI) or hypoxemic load measurements—better predict mortality within 10 years.MethodsAdults with symptoms suggestive of sleep apnea and airway disease who underwent both polysomnography and spirometry plus bronchodilator response tests between 2000 and 2018 were included and divided into four groups according to presence of COPD and moderate-to-severe OSA (AHI ≥15/h). We estimated mortality using a Cox model adjusted for demographic/anthropometric covariates and comorbidities; this was called clinical model. To evaluate prognostic performance, we compared the concordance index (C-index) between clinical model and extended models, which incorporated one of polysomnographic indices—AHI, sleep time spent with SpO₂ < 90% (TS90), and mean and lowest SpO₂.ResultsAmong 355 participants, patients with COPD alone (57/355, 16.1%) and COPD–OSA overlap syndrome (37/355, 10.4%) had increased all-cause mortality than those who had neither disease (152/355, 42.8%) (adjusted HR, 2.98 and 3.19, respectively). The C-indices of extended models with TS90 (%) and mean SpO₂ were significantly higher than that of clinical model (0.765 vs. 0.737 and 0.756 vs. 0.737, respectively; all P < 0.05); however, the C-index of extended model with AHI was not (0.739 vs. 0.737; P = 0.15).ConclusionsIn this cohort with symptoms of sleep apnea and airway disease, patients with overlap syndrome had increased mortality, but not higher than in those with COPD alone. The measurement of hypoxemic load, not AHI, better predicted mortality.     

Oral implant treatment for elderly patients

随着材料和技术的进步,现代口腔种植学得到了快速的发展。种植牙已成为恢复缺失牙的首选治疗方式。尽管在健康成人中,种植牙已经取得了很高的成功率,但对于老龄患者,随着身体机能的下降和伴发其他系统性疾病,种植治疗的风险相应地增加。老龄患者在进行种植治疗时应该考虑哪些影响因素以及如何预防可能的风险和并发症,应引起口腔种植医生的高度重视。本文对老龄患者口腔种植治疗的特殊性、种植成功率、老年患者的全身系统疾病考量和用药考量等方面进行探讨,以供临床参考。