Biomechanical characterization of firefighters running under different rescue tasks.

The biomechanical characteristics of runs in firefighters with different rescue tasks are unclear. This study aimed to explore the biomechanical characteristics of firefighters running in different rescue tasks and provide theoretical and practical references for firefighter training and occupational injury prevention. Eighteen professional healthy male firefighters were randomly selected as participants and tested running on different rescue tasks: wearing firefighting protective clothing (FPC), FPC+carrying a gas can (20 kg, FPC+ C), and FPC+carrying a mannequin (60 kg, FPC+M). Eight Qualisys infrared cameras and an AMTI 3D force measurement platform were used for the participant's acquisition of lower limb kinematic/kinetic data. The results showed that gait velocity and stride length of the FPC+GC and FPC+ M rescue tasks were significantly decreased compared to the FPC rescue task, while the support time was significantly increased. Compared to the FPC rescue task, the FPC+GC rescue task showed significant decreases in vertical ground reaction force (vGRF), minimum ankle dorsiflexion angle, and the maximum ankle plantarflexion power. In contrast, the FPC+M rescue task demonstrated significant increases in ankle range of motion, maximum hip extension angle, minimum knee flexion angle, maximum ankle dorsiflexion angle, maximum hip extension moment, maximum knee flexion moment, maximum hip flexion power, and hip and knee stiffness while exhibiting significant decreases in minimum ankle dorsiflexion angle. Compared to the FPC+ GC rescue task, the FPC+M rescue task exhibited significant increases in the maximum hip extension angle, minimum knee flexion angle, maximum ankle dorsiflexion angle, maximum hip flexion moment, maximum hip extension moment, maximum knee flexion moment, maximum ankle plantarflexion moment, maximum hip flexion power, maximum ankle dorsiflexion power, hip stiffness, and vGRF. Conversely, it showed significant decreases in the maximum knee flexion power. In conclusion, compared to the FPC rescue task, the FPC+GC and FPC+M rescue tasks altered the firefighter's gait performance, as evidenced by decreased gait velocity and stride length and increased support time. FPC+M rescue task would increase firefighter's risk of hip and knee injuries. Therefore, we suggest firefighters increase their strength training of the trunk, hip, and knee joint muscles as part of their daily training programs under large weight load status (60 kg and above) to reduce injury risk during rescue tasks.

The effect of mobile phone task and age on gait: A systematic review and meta-analysis.

Objective: Mobile phone usage while performing postural-locomotor tasks is everyday activity across persons of all ages in various environmental contexts and health conditions. However, it is also an important factor contributing to accidents. To lower the risk of pedestrian accidents, this meta-analysis aimed to examine how mobile phones affect pedestrian gait and identify how mobile phone tasks and participant age affect gait differently. Methods: Electronic database searches were performed in The Cochrane Library, PubMed, and Medline. Two examiners evaluated the eligibility and quality of included studies using the Downs and Black checklist. The mean differences (MD) or standardized mean differences (SMD) were calculated for each outcome. Subgroup analyses were used to compare the differential effects of mobile phone task and participant age on gait. Results: Among 22 eligible studies, 592 participants in 10 countries were analyzed in this meta-analysis. The overall meta-analysis showed that using a mobile phone significantly decreased pedestrian gait velocity (SMD = -1.45; 95% CI: -1.66 to -1.24; p < 0.00001; I2 = 66%), step length (SMD = -1.01; 95% CI: -1.43 to -0.59; p < 0.00001; I2 = 82%), and stride length (SMD = -0.9; 95% CI: -1.19 to -0.60; p < 0.00001; I2 = 79%), significantly increased pedestrian step time (SMD = 0.77; 95% CI: 0.45 to 1.08; p < 0.00001; I2 = 78%), stride time (SMD = 0.87; 95% CI: 0.69 to 1.06; p < 0.00001; I2 = 24%), step width (SMD = 0.79; 95% CI: 0.34 to 1.24; p = 0.0006. I2 = 75%), double support time (SMD = 1.09; 95% CI: 0.86 to 1.31; p < 0.00001; I2 = 42%), and double support (%gait cycle, %GC) (MD = 2.32; 95% CI: 1.75 to 2.88; p < 0.00001; I2 = 26%). Conclusion: In summary, the effects of mobile phone tasks and participant age on gait were inconsistent. Our study found that resource-intensive tasks (texting and reading) significantly reduced gait velocity, and step time; however, small resource-intensive tasks (calling, talking, and dialing) did not affect these outcomes. In contrast to young adults, step length and step time were not affected by mobile phone use in older adults. Tips: Pedestrians should consider using a mobile phone in their daily lives according to the application scenarios (walking environment, the complexity of mobile phone tasks, pedestrians' task processing abilities, etc.) as appropriate to avoid dangerous accidents. Systematic Review Registration: identifier CRD42022358963.

Meta-Analysis of the Effect of Different Exercise Mode on Carotid Atherosclerosis.

(1) Background: There is increasing evidence showing the health benefits of exercise on carotid atherosclerosis. However, little is known about the different exercise modes for carotid atherosclerosis. This study was designed to perform a meta-analysis of effect of different exercise modes on carotid atherosclerosis so as to provide evidence-based suggestions for the prevention and management of cardiovascular and cerebrovascular diseases. (2) Methods: Six databases were systematically searched to identify randomized trials that compared exercise to a non-exercise intervention in patient with carotid atherosclerosis. We a priori specified changes in cIMT, TC, LDL-C, and HDL-C biomarkers as outcomes. (3) Results: Thirty-four trials met the eligibility criteria, comprising 2420 participants. The main analyses showed pronounced differences on cIMT (MD = -0.06, 95%CI (-0.09, -0.04), p < 0.00001, TC (MD = -0.41, 95%CI (-0.58, -0.23), p < 0.00001), LDL-C (MD = -0.31, 95%CI (-0.43, -0.20), p < 0.00001), and HDL-C (MD = 0.11, 95%CI (0.04, 0.19), p = 0.004), which significantly reduced the risk factors of carotid atherosclerosis disease. In the different exercise modes, the effect was pronounced for aerobic exercise for all outcomes except TC; high-intensity interval exercise also showed significance for all outcomes except TC and HDL-C; aerobic exercise combined with resistance exercise did not affect any outcome except HDL-C; (4) Conclusions: Exercise has a prominent prevention and improvement effect on carotid atherosclerosis. In the perspective of exercise pattern, aerobic exercise and high-intensity intermittent exercise can improve carotid atherosclerosis; however, aerobic exercise has a more comprehensive improvement effect.

The effects of proprioceptive neuromuscular facilitation in treating chronic low back pain: A systematic review and meta-analysis.

BACKGROUND: Proprioceptive neuromuscular facilitation (PNF) has been widely used in the clinical treatment of chronic low back pain (LBP) in recent years. However, its role remains controversial and it is unclear whether PNF offers more advantages for patients with chronic LBP. OBJECTIVE: The purpose of this systematic review is to evaluate the evidence on the effect of PNF on pain, waist function, pulmonary function and dynamic balance in patients with chronic LBP. METHODS: Seven English and Chinese electronic databases were searched to identify articles published from 1970 to February 2020. Relevant randomized controlled trials (RCTs) were selected by two independent reviewers to investigate PNF in treatment of chronic LBP. Data extraction was performed by the same reviewers. RESULTS: Twelve eligible trials involving 410 participants were included in this meta-analysis. Compared with the control group, the aggregated results suggested that PNF showed beneficial effects in relieving pain (SMD =-1.17; 95% CI: -1.50 to -0.84; p< 0.00001) and improving waist functional disability (MD =-1.63; 95% CI: -1.89 to -1.37; p< 0.00001). In addition, PNF was shown to have a significant effect on pulmonary function (MD = 0.65; 95% CI: 0.26 to 1.03; p= 0.001). However, the results of the study show that PNF could not significantly improve dynamic balance in patients with chronic LBP compared with the control group (MD =-0.04; 95% CI: -2.16 to 2.08; p= 0.97). A high risk of bias occurred in the areas of blinding (i.e., participants/personnel and outcome assessment). CONCLUSIONS: PNF showed more beneficial effects in pain relief and waist function improvement in patients with chronic LBP in the short term (4 to 8 weeks of intervention) or at 12-week follow-up and also played a positive role in pulmonary function. However, no significant effect of PNF on dynamic balance was found compared with the control group. However, these results have certain limitations, and these conclusions were supported by low-quality data. Therefore, articles that are methodologically reasonable and more authoritative are required to verify the effects. In addition, articles with long-term follow-up and other outcomes are needed to confirm additional findings.

Effects of non-invasive brain stimulation on walking and balance ability in Parkinson's patients: A systematic review and meta-analysis.

Objective: To investigate and contrast the effects of non-invasive brain stimulation (NIBS), including repeated transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS), on walking and balance ability in patients with Parkinson's disease (PD). Methods: The PubMed, Embase, Medline, Cochrane, CNKI, and Chinese WanFang databases were searched up to June 2022. Quality assessment was performed using the Cochrane Collaboration's risk-of-bias guidelines, and the standardized mean differences (SMD) or mean differences (MD) for each outcome were calculated. Results: Among 32 eligible studies, including 1,586 participants were analyzed in this meta-analysis. The results of the meta-analysis showed that NIBS was effective in improving UPDRS-III scores (MD = -2.07; 95% CI, -2.62 to -1.53; P < 0.00001; I 2 = 6%) and variables associated with the ability of walk such as step width (SMD = 0.35; 95% CI, 0.16-0.55; P = 0.0005; I 2 = 38%), cadence (SMD = 0.3; 95% CI, 0.05 to 0.55; P = 0.02; I 2 = 25%), and 6MWT (MD = 62.86; 95% CI, 39.43-86.29; P < 0.00001; I 2 = 0%). In subgroup analyses across intervention types, UPDRS-III scores (rTMS: MD = -2.54; 95% CI, -3.16 to -1.92; P < 0.00001; I 2 = 0%; tDCS: MD = -1.20; 95% CI, -1.99 to -0.40; P = 0.003; I 2 = 0%) and TUGT time (rTMS: MD = -4.11; 95% CI, -4.74 to -3.47; P < 0.00001; I 2 = 0%; tDCS: MD = -0.84; 95% CI, -1.48 to -0.21; P = 0.009; I 2 = 0%) significantly improved. Moreover, our results also showed that compared to tDCS, rTMS was more significant in improving UPDRS-III scores and TUGT time (p < 0.05). Conclusion: NIBS benefits some walking ability variables but not balance ability in 36 patients with PD. The rTMS significantly improved UPDRS-III scores and TUGT time compared to tDCS. Further studies are needed to determine the optimal protocol and to illuminate effects based on the ideal target brain regions, stimulation intensity, timing, and type of intervention. Systematic review registration: http://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022350782.

Effect of liuzijue qigong on patients with stable chronic obstructive pulmonary disease: A systematic review and meta-analysis.

BACKGROUNDS: Chronic obstructive pulmonary disease (COPD) is a common, preventable disease of airflow limitation that accounts for the third leading deaths of any disease process in the worldwide. Health benefits of liuzijue qigong (LQG) on patients with stable COPD has been assessed. This study was designed to perform a systemic review and meta-analysis of the effect of Liuzijue breathing exercise on patients with stable COPD. METHODS: Published articles from 1970 to December 2020 were conducted using electronic searches. Two independents reviewers conducted data extraction. The Cochrane risk of bias assessment tool was used to evaluate the quality of the included studies. RESULTS: A total of 16 eligible trials with 1039 patients with stable COPD were identified. Compared with control group, the pool meta-analysis of LQG showed a significant improvement in forced expiratory volume in one second (FEV1) (MD = -0.16, 95% CI [0.09, 0.23], P < .00001), FEV1% (MD = 9.71, 95% CI [8.44, 10.98], P < .00001), the ratio of forced expiratory volume to forced vital capacity in the first second (FEV1/FVC [%]) (MD = 4.81, 95% CI [2.12, 7.51], P = .0005), 6 minutes walking distance (6MWD) (MD = 21.89, 95% CI [14.67, 29.11], P < .00001), health-related quality of life (SMD = -0.84, 95% CI [-1.12,-0.55], P < .00001) and modified medical research council dyspnea scale (mMRC) (MD = -0.73, 95% CI [-0.96, -0.50], P < .00001). The observed effect was more pronounced for short term and medium-term duration interventions of study. It also showed improvements in the secondary outcome measures by LQG. CONCLUSIONS: In this systematic review and meta-analysis, LQG can improve lung ventilation function, exercise endurance and health-related quality of life of patients with stable COPD. ETHIC AND DISSEMINATION: This study is a systematic review and it does not involve harming to the rights of participants. Ethical approval will not be require for this study. The research results may be published in a peer-reviewed journals.

[Clinical effect of "Jin's three-needle" therapy and motor relearning regimen on the upper limb motor function in patients with ischemic stroke].

OBJECTIVE: To explore the clinical effect of "Jin's three-needle" therapy and motor relearning regime for the recovery of upper limb motor function in the patients with ischemic stroke. METHODS: A total of 60 patients with ischemic stroke were randomly divided into an experiment group (30 cases) and a control group (30 cases). In the control group, the routine rehabilitation regimen was adopted. In the experimental group, on the base of the treatment regimen as the control group, the "Jin's three-needle" therapy was supplemented. The neurological function deficit score was used to assess the neurological function. The modified Fugel-Meyer assessment for upper extremities (FMA) and motor assessment scale (MAS) were adopted to assess the upper limb motor function in patients. The modified Barthel Index (MBI) was used to evaluate the activity of daily living (ADL) in patients. RESULTS: After treatment, the neurological function deficit score, the upper limb motor function (FMA and MAS) and ADL (MBI) were all improved obviously as compared with those before treatment (P<0.05). In the experimental group, the reducing range of neurological function deficit score (difference value) was larger than that in the control group (P<0.05). The increases of FMA score (upper arm function), the total score of MAS, the score for hand movement in MAS and the score for advanced hand activities of MAS, as well as MBI score in the experimental group were significantly larger than those in the control group successively (P<0.05). CONCLUSION: "Jin's three-needle" therapy combined with exercise relearning regimen effectively reduces the degree of neurological deficit and improve the upper limb motor function and ADL in patients with ischemic stroke.

Hypolipidemic effects of Myrica rubra extracts and main compounds in C57BL/6j mice.

The present study evaluated the antihyperlipidemic activity of myricetin, myricetrin, the alcohol fraction (AF) and the ethyl acetate fraction (EF) obtained from the bark of Myrica rubra (MR) in high-fat and high-cholesterol (HFHC) induced hyperlipidemic C57BL/6j mice. Mice were treated with myricetin, myricetrin, AF and EF with a dose of 130 mg per kg per day for 35 days. After treatment, serum parameters including total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), total bile acids (TBA), etc., were examined. The results revealed that EF showed the highest weight lowering activity (P < 0.01). All tested samples decreased the levels of the TC, TG, LDL-C, TBA and LPS (lipopolysaccharide) content in the serum of mice to different extents. Liver fat deposition was significantly reduced after myricetin, myricetrin, AF and EF therapy (P < 0.01). Additionally, the cell size of epididymal adipose tissue was also decreased in myricetin, AF and EF groups (P < 0.05). The antihyperlipidemic activity of these samples may be attributed to the inhibition of lipid synthesis via suppressing the expression of HMGCR (3-hydroxy-3-methylglutaryl coenzyme A reductase) and ACC1 (acetyl-CoA carboxylase), promoting the metabolism and excretion of lipids via up-regulating the expression of SREBP2 (sterol regulatory element binding proteins), LDLR (low density lipoprotein receptor), UCP2 (uncoupling protein 2) and CYP7A1 (cholesterol 7α-hydroxylase). These results may provide a powerful foundation for seeking and utilizing Myrica rubra bio-active compounds for the treatment of hyperlipidemia and cardiovascular diseases.

Purification of α-glucosidase from mouse intestine by countercurrent chromatography coupled with a reverse micelle solvent system.

Countercurrent chromatography coupled with a reverse micelle solvent was applied to separate α-glucosidase, which is stable at pH 6.0-8.8, 15-50°C. The separation conditions are as follows: stationary phase: pH 4.0 Tris-HCl buffer phase containing 50 mM Tris-HCl and 50 mM KCl; mobile phase A: isooctane containing 50 mM anionic surfactant sodium di(2-ethylhexyl)sulfosuccinate; mobile phase B: 50 mM Tris-HCl buffer containing 500 mM KCl (pH 8.0); In total, 25 mL (23.9 mg) crude enzyme was injected through the injection valve, the enzymatic reaction and sodium dodecylsulfate polyacrylamide gel electrophoresis results imply that the activity of purified α-glucosidase is 6.63-fold higher than that of the crude enzyme. Therefore, countercurrent chromatography coupled with a reverse micelle solvent is capable for protein separation and enrichment.