人工智能辅助软件可提升疲劳状态下放射科规培医师对肺结节的检测效能

目的:探讨在人工智能(AI)肺结节检测软件的辅助下能否提升疲劳状态的放射科规培医师对肺结节的检测效能。方法:搜集182例患者的1 mm薄层胸部CT图像,有一位放射科规培医师分别在3种模式下进行阅片:正常状态下独立阅片(A组)、疲劳状态下(即一天日常工作满8小时以上)独立阅片(B组)、疲劳状态下使用AI软件辅助阅片(C组),三种阅片模式均间隔洗脱期(2周),分别记录每次阅片时检出结节的位置、大小和数目。将3次肺结节检出结果与金标准(由2位从事胸部影像诊断超过8年的中级医师结合AI筛查结果分别作出诊断,再由1位从事胸部影像诊断超过15年的高级医师最终审核确定)进行比较,计算敏感度和(患者)人均假阳性(误诊)结节数来评价3种模式的检测效能。结果:经金标准确认1281个肺结节,A组检出真阳性结节592个、假阳结节297个,敏感度46.21%,人均误诊结节数为1.63;B组检出真阳性结节517个、假阳结节225个,敏感度40.36%,人均误诊结节数为1.24;C组检出真阳性结节995个、假阳结节165个,敏感度77.67%,人均误诊结节数为0.91。B组的敏感度和人均误诊结节数均较A组降低,差异均有统计学意义(P<0.05);C组的敏感度较B组提高,且人均误诊结节数降低,差异均有统计学意义(P<0.05);C组的敏感度较A组提高,人均误诊结节数降低,差异均有统计学意义(P<0.05)。结论:疲劳显著降低了放射科规培医师对肺结节的检测效能,但在AI软件辅助下能明显提高疲劳状态下放射科规培医师对肺结节的检出效能,甚至超过其正常状态下的水平。     

The interaction of acute physical fatigue with three traditional functional performance tests and the reactive balance test

ObjectivesTo assess the impact of acute physical fatigue on traditional and neurocognitive functional performance tests in recreational athletes.Designrandomized counterbalanced cross-over study, pre-post designSettinglaboratoryParticipantsTwenty recreational athletes (age = 24 ± 3 years)Main outcome measuresWe evaluated fatigue impairments following a 30 s all-out effort in three traditional and one neurocognitive functional performance test. The traditional functional performance tests encompassed the single leg hop for distance (SLH), countermovement jump (CMJ) and Y-balance test (YBT). The neurocognitive functional performance test encompassed the reactive balance test (RBT). A 30 s modified Wingate was used to induce acute physical fatigue.ResultsAcute physical fatigue was successfully induced as indicated by a significant increase in heart rate, systolic blood pressure, blood lactate levels and rating of perceived exertion (p < 0.001). Acute physical fatigue induced significant decreases in RBT accuracy (p = 0.004) and SLH performance (p < 0.001). YBT, CMJ and RBT visuomotor reaction time remained unaffected by acute physical fatigue.ConclusionsAcute physical fatigue impairs SLH performance and decreases accuracy in the RBT. YBT and CMJ performance remained unaffected by acute physical fatigue. Clinicians should be aware of this divergent neurocognitive functional impairments caused by one all-out effort to allow well-informed selection of functional performance tests.     

Effect of qigong for sleep disturbance-related symptom clusters in cancer: a systematic review and meta-analysis

ObjectivesTo examine the effects of qigong interventions on sleep disturbance-related symptom clusters for cancer patients and to explore the possible mediating role of fatigue and depression in affecting sleep.MethodsIn this systematic review and meta-analysis, a systematic search was conducted through October 2020 by searching multiple English and Chinese databases. Inclusion was limited to randomized controlled trials that measured the effect of qigong on sleep and fatigue/depressive symptoms in cancer patients. Eleven studies involving 907 cancer patients were included in the systematic review, whereas the meta-analysis included ten studies with 851 cancer patients.ResultsThe most commonly investigated form of qigong was Taichi, and the intervention length ranged from 10 days to 6 months. All studies employed self-reported measurements. Overall, qigong significantly improved sleep (SMD = −1.28, 95% CI: −2.01, −0.55) and fatigue (SMD = −0.89, 95% CI: −1.59, −0.19) in cancer patients post-intervention, but not depressive symptoms (SMD = −0.69, 95% CI: −1.81, 0.42). Notably, the benefits on sleep and fatigue became non-significant after 3 months. Qigong's effect on sleep was significantly mediated by its effect on fatigue (β = 1.27, SE = 0.24, p = 0.002), but not depressive symptoms (β = 0.53, SE = 0.26, p = 0.106).ConclusionsQigong can be recommended for improving sleep disturbance-fatigue symptom clusters in the cancer population, while qigong's benefit on sleep is likely based on its effect on reducing fatigue. Future qigong studies should adopt more rigorous design and employ strategies to maintain longevity of intervention benefits.     

Negative Impacts of Prolonged Standing at Work on Musculoskeletal Symptoms and Physical Fatigue: The Fifth Korean Working Conditions Survey

PurposeWe aimed to investigate variations in the risk of low back pain (LBP), lower extremity muscle pain, and whole body fatigue according to differences in prolonged standing work hours in relation to risk factor exposure and rest frequency.Materials and MethodsFrom the fifth Korean Working Conditions Survey data collected in 2017, data for 32970 full-time workers who worked for more than 1 year at their present job were analyzed. We classified the workers according to exposure to fatigue or painful postures, carrying heavy objects, performance of repetitive movements that burden the musculoskeletal system, and how often they took a break. Relationships between time spent in a standing posture at work and risks of LBP, lower extremity muscle pain, and whole body fatigue were analyzed by multivariate logistic regression.ResultsOf the full-time workers in the survey, 48.7% worked in a standing position for more than half of their total working hours. A higher odds ratio (OR) value for lower extremity muscle pain was observed in female not exposed to carrying heavy objects [OR: 3.551, 95% confidence interval (CI): 3.038–4.150] and not exposed to performing repetitive movements (OR: 3.555, 95% CI: 2.761–4.557).ConclusionChanges in work methodologies are needed to lower the number of hours spent in a prolonged standing posture at work, including being able to rest when workers want to do so, to reduce pain and fatigue.     

Minimal tooth preparation for posterior monolithic ceramic crowns: Effect on the mechanical behavior,reliability and translucency

ObjectiveDespite the increased use of monolithic crowns, their performance has yet to be determined when the minimal tooth preparation (MTP) principle is considered. The goal of this study was to evaluate the effect of MTP on the mechanical behavior, reliability and translucency of posterior monolithic ceramic crowns.MethodsDentin analogues were machined using two preparation designs (0.5 or 1 mm reduction) to receive first molar crowns in order to evaluate the monolithic crown performance. Next, 126 crowns were divided (21/g) according to the material (High translucent zirconia – YZHT, Zirconia reinforced lithium silicate – ZLS and Hybrid ceramic – HC) and thickness (0.5 or 1 mm). Tensile stress concentration was calculated using the finite element method. The crowns were adhesivelly cemented and step stress fatigued to calculate reliability for missions at 600 and 1000 N. Translucency was analyzed in 10 discs of each material and thickness.ResultsHigher stress concentration was found in thinner crowns and those with higher elastic modulus. YZHT crowns were suspended when fatigue reached 1500 N load, thus 1-parameter Weibull was used to analyze the data. Reliability was only affected by thickness at 1000 N. ZLS.5 showed lower survival than HC.5, which was similar to the groups that presented 100% survival. YZHT showed the highest strength and data scattering. ZLS1 (22.3 ± 1.4) presented higher translucency than HC1 (19.2 ± 0.6) and YZHT1 (12.0 ± 2.9), whereas ZLS.5 and HC.5 were similar to each other (26.5 ± 2.3, 26.7 ± 2.2) and superior to YZHT.5 (12.7 ± 1.2).SignificanceHC.5 combined high reliability and translucency with low stress concentration, yielding better crown performance and tooth preservation.     

Survival probability of zirconia-reinforced lithium silicate ceramic: Effect of surface condition and fatigue test load profile

ObjectivesThe present investigation evaluated the step stress accelerated test (SSALT) load profiles on the survival probability of a glass ceramic under two surface conditions (polished or roughened).MethodsSuprinity–ZLS blocks (Vita Zhanfabrik) were shaped into cylinders, cut in a sawing machine, and crystalized according to the manufacturer's instructions. 60 discs were obtained (Ø = 12 mm, thickness = 1.2 mm) and randomly assigned into two surface conditions: “p” polished surface (400–1200-grit SiC papers), and “r” roughened surface (200-grit SiC papers). Profilometry was performed in all discs to evaluate average surface roughness prior to flexural fatigue strength testing. 3 discs of each group were submitted to biaxial flexural strength in an universal testing machine (0.5 mm/min) and the mean load to failure (N) was calculated to determine SSALT profiles. 27 specimens per surface condition were assigned into three profiles – Mild (n = 9), Moderate (n = 9), and Aggressive (n = 9), and submitted to the fatigue test (60–320 N, 140,000 cycles at 1.4 Hz). The results were analyzed using the Kaplan-Meier and Wilcoxon tests (5%), 2-way ANOVA and Tukey test (α = 5%).ResultsKaplan-Meier and generalized Wilcoxon showed (P = 0.002) that polished groups showed higher survival probability than roughened condition (P < 0.05). A rough internal surface impacted deleteriously on the fatigue strength and reliability of ZLS ceramic. Both surface conditions were more sensitive to the aggressive profile than the other profiles, even worst for the roughened group. Regardless the load profile, 0% survival probability was observed at 384 MPa for polished condition. While for roughened, aggressive tested specimens did not survived 147 MPa followed by moderate at 312 MPa and mild at 384 MPa. The failure modes showed fracture marks originating from superficial grooves for both surface conditions.SignificancePolished specimens are sensitive to the load profile variation, confirming the effect of surface morphology on the fatigue results.     

Cyclic contact fatigue resistance of ceramics for monolithic and multilayer dental restorations

ObjectiveTo evaluate the cyclic contact fatigue resistance and failure mode of ceramics for monolithic and multilayer restorations.MethodsCeramic structures (10 mm × 1.8 mm) were fabricated as follows (n = 28): (1) CAD-on- trilayer structure composed of Y-TZP (yttria stabilized tetragonal zirconia polycrystal- IPS e.max ZirCAD) infrastructure, fusion glass–ceramic (IPS e.max CAD Crystall/Connect) and lithium disilicate-based glass–ceramic (IPS e.max CAD); (2) ZFC- bilayer structure composed of Y-TZP infrastructure veneered by a fluorapatite glass–ceramic (IPS e.max Ceram); (3) LDC- monolithic lithium-disilicate glass–ceramic (IPS e.max CAD); and (4) YZW- monolithic Y-TZP (Zenostar Zr Translucent). All ceramics structures were bonded to a dentin analog substrate (G10). Specimens were submitted to cyclic contact fatigue test in a pneumatic cycling machine with 80 N load and 2 Hz frequency in distilled water at 37 °C. Test was interrupted after 10⁴, 10⁵, 5 × 10⁵ and 10⁶ cycles and the presence or absence of failure was recorded. Fatigue data were analyzed using Kaplan–Meier (log rank) and Holm–Sidak tests (α = 0.05). The relationship between the type of crack leading to failure and the experimental group was analyzed using chi-square test (α = 0.05).ResultsThere was no statistical difference between CAD-on and YZW groups (p = 0.516), which presented the highest survival rates after cyclic loading, followed by ZFC and LDC groups (p < 0.01). There was a significant relationship between type of crack and experimental group (p < 0.001). LDC specimens showed the greatest frequency of radial cracks, while cone cracks were more prevalent for ZFC and CAD-on specimens.SignificanceMonolithic Y-TZP (YZW) showed similar fatigue resistance to CAD-on multilayer specimens, but different failure mode. Monolithic lithium disilicate glass–ceramic (LDC) and Y-TZP conventionally veneered by glass–ceramic (ZFC) showed lower survival time under fatigue.     

A randomized clinical trial on the efficacy of a patient-adapted autonomous exercise regime for patients with head and neck cancer

Patients undergoing surgical therapy of head and neck malignancies are known to exhibit a high number of comorbidities and frequently present a high nosocomial morbidity. Physiotherapy (PT) improves the clinical course of patients after extensive surgery. The aim of this study was to establish and then compare an additional individualized autonomous exercise plan with standard physiotherapy. 69 consecutive patients undergoing surgical treatment of head and neck cancer were randomized into two groups. The control group received standard clinical physiotherapy, the intervention group an additional autonomous exercise plan, adapted to the patient's performance profile. The patients randomized to the intervention group showed significantly fewer signs of fatigue (5.5 ± 3.5 vs. 3.7 ± 2.7, p = 0.048) and fewer digestive problems (4.7 ± 3.3 vs. 2.3 ± 2.7; p = 0.009) compared with the patients of the control group. In addition, a significantly shorter hospital stay was observed (17.7 ± 6.3 vs. 13.4 ± 3.4 days, p = 0.005), which was positively influenced by the early start of the exercises (r = 0.623, p = 0.001) and frequent practice (r = 0.432, p = 0.031). Patients with head and neck cancer therapy can benefit from an autonomous, individualized exercise plan. In coordination with the physiotherapists, mobilization should be as early and intensive as possible.     

Neurophysiological Correlates of Fatigue in Multiple Sclerosis

Examining fatigue may be beneficial for nurse practitioners to intervene in the care of patients with multiple sclerosis (MS). We measured the relationship of fatigue severity with event-related potentials during electroencephalogram and diffusion basis spectrum imaging/magnetic resonance imaging in 11 participants with relapsing-remitting MS and 5 healthy controls. Data were analyzed to measure brain activity during event-related potentials to responses to cue (correct response) and distractor (incorrect response) using a cognitive performance task. Nurse practitioners caring for patients with MS have an important role in monitoring fatigue severity.