AFM-based spherical indentation of a brush-coated soft material: modeling the bottom effect.

It is a common practice in the atomic force microscopy (AFM)-based studies of living cells to differentiate them by values of the elastic (Young's) modulus, which is supposed to be an effective characteristic of the mechanical properties of a cell as a heterogeneous matter. The elastic response of a cell to AFM indentation is known to be affected by a relative distance from an AFM probe to a solid support on to which the cell is cultured. Besides this so-called bottom effect, AFM measurements may carry significant information regarding the effect of molecular brushes covering living cells. Here, we develop a mathematical model for determining the intrinsic effective Young's modulus of a single brush-coated cell from the force-indentation curve with the bottom effect taken into account. The mathematical model is illustrated with the example of AFM data on testing of an eukaryotic cell taken from the literature.

Short-term environmental nitrogen dioxide exposure and neurology clinic visits for headaches, a time-series study in Wuhan, China.

BACKGROUND: Previous studies showed the adverse impacts of air pollution on headache attacks in developed countries. However, evidence is limited to the impact of exposure to air pollutants on headache attacks. In this study, we aimed to explore the impact of nitrogen dioxide (NO2) exposure on neurology clinic visits (NCVs) for headache onsets. METHODS: Records of NCVs for headaches, concentrations of ambient NO2, and meteorological variables were collected in Wuhan, China, from January 1st, 2017, to November 30th, 2019. A time-series study was conducted to investigate the short-term effects of NO2 exposure on daily NCVs for headaches. Stratified analyses were also computed according to season, age, and sex, and the exposure-response (E-R) curve was then plotted. RESULTS: A total of 11,436 records of NCVs for headaches were enrolled in our study during the period. A 10-µg/m3 increase of ambient NO2 corresponded to a 3.64% elevation of daily NCVs for headaches (95%CI: 1.02%, 6.32%, P = 0.006). Moreover, females aged less than 50 years of age were more susceptible compared to males (4.10% vs. 2.97%, P = 0.007). The short-term effects of NO2 exposure on daily NCVs for headaches were stronger in cool seasons than in warm seasons (6.31% vs. 0.79%, P = 0.0009). CONCLUSION: Our findings highlight that short-term exposure to ambient NO2 positively correlated with NCVs for headaches in Wuhan, China, and the adverse effects varied by season, age, and sex.

Combination of On-Line and Off-Line Two-Dimensional Liquid Chromatography-Mass Spectrometry for Comprehensive Characterization of mAb Charge Variants and Precise Instructions for Rapid Process Development.

Charge variants, as an important quality attribute of mAbs, must be comprehensively characterized and monitored during development. However, due to their complex structure, the characterization of charge variants is challenging, labor-intensive, and time-consuming when using traditional approaches. This work combines on-line and off-line 2D-LC-MS to comprehensively characterize mAb charge variants and quickly offer precise instructions for process development. Six charge variant peaks of mAb 1 were identified using the developed platform. Off-line 2D-LC-MS analysis at the peptide level showed that the acidic peak P1 and the basic peaks P4 and P5 were caused by the deamidation of asparagine, the oxidation of methionine, and incomplete C-terminal K loss, respectively. On-line 2D-LC-MS at the intact protein level was used to identify the root causes, and it was found that the acidic peak P2 and the basic peak P6 were due to the glutathionylation of cysteine and succinimidation of aspartic acid, respectively, which were not found in off-line 2D-LC-MS because of the loss occurring during pre-treatment. These results suggest that process development could focus on cell culture for adjustment of glutathionylation. In this paper, we propose the concept of precision process development based on on-line 2D-LC-MS, which could quickly offer useful data with only 0.6 mg mAb within 6 h for precise instructions for process development. Overall, the combination of on-line and off-line 2D-LC-MS can characterize mAb charge variants more comprehensively, precisely, and quickly than other approaches. This is a very effective platform with routine operations that provides precise instructions for process development within hours, and will help to accelerate the development of innovative therapeutics.

Effect of peer videorecording feedback CPR training on students' practical CPR skills: a randomized controlled manikin study.

BACKGROUND: The aim of this study was to compare one-month acquisition and half-a-year quality retention of cardiopulmonary resuscitation (CPR) skills after initial training of medical students between peer videorecording feedback training (PVF) and traditional peer verbal feedback training (TVF). METHODS: Participants were randomly assigned to the PVF group (n = 62) and the TVF group (n = 65). All participants received a 45-min CPR training program performed by an American Heart Association basic life support-certified instructor, and then they began two hours of practice in groups. During interactive peer learning, students cooperated in couples of a doer and a helper to realize maximization of each other's learning. In the PVF group, training performance feedback came from peers based on practice videorecording. In the TVF group, feedback came from peers verbally without videorecording. CPR quality was tested at 1 and 6 months after training. RESULTS: After 1 month of initial training, the PVF group had a better presentation of CPR skills acquisition than the TVF group. Compared to the TVF group, the PVF group had significantly higher total scores, compression depth, appropriate compression depth, and complete chest recoil (p < 0.05). Moreover, compression interruption was a significantly positive change in the PVF group compared to the TVF group (p < 0.05). However, after 6 months, proportions of appropriate compression depth in the PVF group were better than those in the TVF group (p < 0.05). The differences in total scores, compression depth, appropriate compression depth, complete chest recoil and compression interruption were non-significant (all p > 0.05). CONCLUSIONS: Compared to TVF, PVF is more effective in enhancing CPR skill acquisition at 1 month. After half a year, CPR skill quality was obviously reduced in both groups, and no difference in CPR quality was found between the two groups.

Establishment and validation of prognosis model for patients with cerebral contusion.

BACKGROUND AND OBJECTIVE: Cerebral Contusion (CC) is one of the most serious injury types in patients with traumatic brain injury (TBI). In this study, the baseline data, imaging features and laboratory examinations of patients with CC were summarized and analyzed to develop and validate a prediction model of nomogram to evaluate the clinical outcomes of patients. METHODS: A total of 426 patients with cerebral contusion (CC) admitted to the People's Hospital of Qinghai Province and Affiliated Hospital of Qingdao University from January 2018 to January 2021 were included in this study, We randomly divided the cohort into a training cohort (n = 284) and a validation cohort (n = 142) with a ratio of 2:1.At Least absolute shrinkage and selection operator (Lasso) regression were used for screening high-risk factors affecting patient prognosis and development of the predictive model. The identification ability and clinical application value of the prediction model were analyzed through the analysis of receiver operating characteristic curve (ROC), calibration curve, and decision curve analysis (DCA). RESULTS: Twelve independent prognostic factors, including age, Glasgow Coma Score (GCS), Basal cistern status, Midline shift (MLS), Third ventricle status, intracranial pressure (ICP) and CT grade of cerebral edema,etc., were selected by Lasso regression analysis and included in the nomogram. The model showed good predictive performance, with a C index of (0.87, 95% CI, 0.026-0.952) in the training cohort and (0.93, 95% CI, 0.032-0.965) in the validation cohort. Clinical decision curve analysis (DCA) also showed that the model brought high clinical benefits to patients. CONCLUSION: This study established a high accuracy of nomogram model to predict the prognosis of patients with CC, its low cost, easy to promote, is especially applicable in the acute environment, at the same time, CSF-glucose/lactate ratio(C-G/L), volume of contusion, and mean CT values of edema zone, which were included for the first time in this study, were independent predictors of poor prognosis in patients with CC. However, this model still has some limitations and deficiencies, which require large sample and multi-center prospective studies to verify and improve our results.

Effect of synchronous online vs. face-to-face cardiopulmonary resuscitation training on chest compression quality: A pilot randomized manikin study.

OBJECTIVES: The aim of the study was to compare the effect of synchronous online and face-to-face cardiopulmonary resuscitation (CPR) training on chest compressions quality in a manikin model. METHODS: A total of 118 fourth-year medical students participated in this study. The participants were divided into two groups: the online synchronous teaching group and the face-to-face group. Then, the participants were further randomly distributed to 1 of 2 feedback groups: online synchronous teaching and training with feedback devices (TF, n = 30) or without feedback devices (TN, n = 29) and face-to-face teaching and training with feedback devices (FF, n = 30) or without feedback devices (FN, n = 29). In the FN group and FF group, instructors delivered a 45-min CPR training program and gave feedback and guidance during training on site. In the TN group and TF group, the participants were trained with an online lecture via Tencent Meeting live broadcasting. Finally, participants performed a 2-min continuous chest compression (CC) during a simulated cardiopulmonary arrest scene without the audiovisual feedback (AVF) device. The outcome measures included CC depth, CC rate, proportions of appropriate depth (50-60 mm) and CC rate (100-120/min), percentage of correct hand location position, and percentage of complete chest recoil. RESULTS: There was little difference in the CC quality between the synchronous online training groups and the face-to-face training groups. There was no statistically significant difference in CC quality between the TN group and FN group. There were also no statistically significant differences between the TF and FF groups in terms of correct hand position, CC depth, appropriate CC depth, complete chest recoil or CC rate. However, the FF group had a higher appropriate CC rate than the TF group (p = 0.045). In the face-to-face training groups, the AVF device group had a significantly greater CC depth, appropriate CC depth, CC rate, and appropriate CC rate. However, there was a lack of statistically significant differences in terms of correct hand position (p = 0.191) and appropriate CC depth (p = 0.123). In the synchronous online training groups, the AVF device had little effect on the CC rate (p = 0.851) and increased the appropriate CC rate, but the difference was not statistically significant (p = 0.178). CONCLUSIONS: Synchronous online training with an AVF device would be a potential alternative approach to face-to-face chest compression training. Synchronous online training with AVF devices seems to be a suitable replacement for face-to-face training to offer adequate bystander CPR chest compression training.

Wearing a N95 mask increases rescuer's fatigue and decreases chest compression quality in simulated cardiopulmonary resuscitation.

OBJECTIVES: N95 mask is essential for healthcare workers dealing with the coronavirus disease 2019 (COVID-19). However, N95 mask causes discomfort breathing with marked reduction in air exchange. This study was designed to investigate whether the use of N95 mask affects rescuer's fatigue and chest compression quality during cardiopulmonary resuscitation (CPR). METHODS: After a brief review of CPR, each participant performed a 2-minute continuous chest compression on a manikin wearing N95 (N95 group, n = 40) or surgical mask (SM group, n = 40). Compression rate and depth, the proportions of correct compression rate, depth, complete chest recoil and hand position were documented. Participants' fatigue was assessed using Borg score. RESULTS: Significantly lower mean chest compression rate and depth were both achieved in the N95 group than in the SM group (p < 0.05, respectively). In addition, the proportion of correct compression rate (61 ± 19 vs. 75 ± 195, p = 0.0067), depth (67 ± 16 vs. 90 ± 14, p < 0.0001) and complete recoil (91 ± 16 vs. 98 ± 5%, p = 0.0248) were significantly decreased in the N95 group as compared to the SM group. At the end of compression, the Borg score in the N95 group was significantly higher than that in the SM group (p = 0.027). CONCLUSION: Wearing a N95 mask increases rescuer's fatigue and decreases chest compression quality during CPR. Therefore, the exchange of rescuers during CPR should be more frequent than that recommended in current guidelines when N95 masks are applied.

Telomeric epigenetic response mediated by Gadd45a regulates stem cell aging and lifespan.

Progressive attrition of telomeres triggers DNA damage response (DDR) and limits the regenerative capacity of adult stem cells during mammalian aging. Intriguingly, telomere integrity is not only determined by telomere length but also by the epigenetic status of telomeric/sub-telomeric regions. However, the functional interplay between DDR induced by telomere shortening and epigenetic modifications in aging remains unclear. Here, we show that deletion of Gadd45a improves the maintenance and function of intestinal stem cells (ISCs) and prolongs lifespan of telomerase-deficient mice (G3Terc-/-). Mechanistically, Gadd45a facilitates the generation of a permissive chromatin state for DDR signaling by inducing base excision repair-dependent demethylation of CpG islands specifically at sub-telomeric regions of short telomeres. Deletion of Gadd45a promotes chromatin compaction in sub-telomeric regions and attenuates DDR initiation at short telomeres of G3Terc-/- ISCs. Treatment with a small molecule inhibitor of base excision repair reduces DDR and improves the maintenance and function of G3Terc-/- ISCs. Taken together, our study proposes a therapeutic approach to enhance stem cell function and prolong lifespan by targeting epigenetic modifiers.

Using three statistical methods to analyze the association between exposure to 9 compounds and obesity in children and adolescents: NHANES 2005-2010.

BACKGROUND: Various risk factors influence obesity differently, and environmental endocrine disruption may increase the occurrence of obesity. However, most of the previous studies have considered only a unitary exposure or a set of similar exposures instead of mixed exposures, which entail complicated interactions. We utilized three statistical models to evaluate the correlations between mixed chemicals to analyze the association between 9 different chemical exposures and obesity in children and adolescents. METHODS: We fitted the generalized linear regression, weighted quantile sum (WQS) regression, and Bayesian kernel machine regression (BKMR) to analyze the association between the mixed exposures and obesity in the participants aged 6-19 in the National Health and Nutrition Examination Survey (NHANES) 2005-2010. RESULTS: In the multivariable logistic regression model, 2,5-dichlorophenol (2,5-DCP) (OR (95% CI): 1.25 (1.11, 1.40)), monoethyl phthalate (MEP) (OR (95% CI): 1.28 (1.04, 1.58)), and mono-isobutyl phthalate (MiBP) (OR (95% CI): 1.42 (1.07, 1.89)) were found to be positively associated with obesity, while methylparaben (MeP) (OR (95% CI): 0.80 (0.68, 0.94)) was negatively associated with obesity. In the multivariable linear regression, MEP was found to be positively associated with the body mass index (BMI) z-score (ß (95% CI): 0.12 (0.02, 0.21)). In the WQS regression model, the WQS index had a significant association (OR (95% CI): 1.48 (1.16, 1.89)) with the outcome in the obesity model, in which 2,5-DCP (weighted 0.41), bisphenol A (BPA) (weighted 0.17) and MEP (weighted 0.14) all had relatively high weights. In the BKMR model, despite no statistically significant difference in the overall association between the chemical mixtures and the outcome (obesity or BMI z-score), there was nonetheless an increasing trend. 2,5-DCP and MEP were found to be positively associated with the outcome (obesity or BMI z-score), while fixing other chemicals at their median concentrations. CONCLUSION: Comparing the three statistical models, we found that 2,5-DCP and MEP may play an important role in obesity. Considering the advantages and disadvantages of the three statistical models, our study confirms the necessity to combine different statistical models on obesity when dealing with mixed exposures.

Plasma Exosome-derived MicroRNAs as Novel Biomarkers of Traumatic Brain Injury in Rats.

Traumatic brain injury (TBI) is a widespread central nervous system (CNS) condition and a leading cause of death, disability, and long-term disability including seizures and emotional and behavioral issues. To date, applicable diagnostic biomarkers have not been elucidated. MicroRNAs (miRNAs) are enriched and stable in exosomes in plasma. Therefore, we speculated that miRNAs in plasma exosomes might serve as novel biomarkers for TBI diagnosis and are also involved in the pathogenesis of TBI. In this study, we first isolated exosomes from peripheral blood plasma in rats with TBI and then investigated the alterations in miRNA expression in exosomes by high-throughput RNA sequencing. As a result, we identified 50 significantly differentially expressed miRNAs, including 31 upregulated and 19 downregulated miRNAs. Then, gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that the most highly correlated pathways that were identified were the MAPK signaling pathway, regulation of actin cytoskeleton, Rap1 signaling pathway and Ras signaling pathway. This study provides novel perspectives on miRNAs in peripheral blood plasma exosomes, which not only could be used as biomarkers of TBI diagnosis but could also be manipulated as therapeutic targets of TBI.

Quality retention of chest compression after repetitive practices with or without feedback devices: A randomized manikin study.

OBJECTIVES: This study was designed to investigate whether an audiovisual feedback (AVF) device is beneficial for quality retention of chest compression (CC) after repetitive practices (RP). METHODS: After completion of a 45-min CC-only cardiopulmonary resuscitation (CPR) training, participants performed 3 sessions of practices on days 1, 3, and 7 under the guidance of an instructor with (RP + AVF) or without (RP) the AVF device. CC quality was determined after each session and was retested at 3 and 12 months. RESULTS: In total, ninety-seven third year university students participated in this study. CC quality was improved after 3 sessions in both the RP and RP + AVF groups. Retests at 3 months showed that the proportions of appropriate CC rate and correct hand position were significantly decreased in the RP group as compared with the last practice (p < 0.05). However, no significant changes in CC quality were observed in the RP + AVF group. However, the proportions of appropriate CC rate, depth, and complete recoil were significantly decreased after 12 months in both RP and RP + AVF groups (p < 0.05). There were no significant differences in these parameters between the RP and the RP + AVF groups at 12 months after RP. CONCLUSION: With RP, the use of an AVF device further improves initial CC skill acquisition and short-term quality retention. However, long-term quality retention is not statistically different between rescuers who receive verbal human feedback only and those who receive additional AVF device feedback after RP.

Exogenous GABA enhances muskmelon tolerance to salinity-alkalinity stress by regulating redox balance and chlorophyll biosynthesis.

BACKGROUND: Salinity-alkalinity stress is one of the major abiotic stresses affecting plant growth and development. γ-Aminobutyrate (GABA) is a non-protein amino acid that functions in stress tolerance. However, the interactions between cellular redox signaling and chlorophyll (Chl) metabolism involved in GABA-induced salinity-alkalinity stress tolerance in plants remains largely unknown. Here, we investigated the role of GABA in perceiving and regulating chlorophyll biosynthesis and oxidative stress induced by salinity-alkalinity stress in muskmelon leaves. We also evaluated the effects of hydrogen peroxide (H2O2), glutathione (GSH), and ascorbate (AsA) on GABA-induced salinity-alkalinity stress tolerance. RESULTS: Salinity-alkalinity stress increased malondialdehyde (MDA) content, relative electrical conductivity (REC), and the activities of superoxide dismutase (SOD), ascorbate peroxidase (APX) and dehydroascorbate reductase (DHAR). Salinity-alkalinity stress decreased shoot dry and fresh weight and leaf area, reduced glutathione and ascorbate (GSH and AsA) contents, activities of glutathione reductase (GR) and monodehydroascorbate reductase (MDAR). By contrast, pretreatment with GABA, H2O2, GSH, or AsA significantly inhibited these salinity-alkalinity stress-induced effects. The ability of GABA to relieve salinity-alkalinity stress was significantly reduced when the production of endogenous H2O2 was inhibited, but was not affected by inhibiting endogenous AsA and GSH production. Exogenous GABA induced respiratory burst oxidase homologue D (RBOHD) genes expression and H2O2 accumulation under normal conditions but reduced the H2O2 content under salinity-alkalinity stress. Salinity-alkalinity stress increased the accumulation of the chlorophyll synthesis precursors glutamate (Glu), δ-aminolevulinic acid (ALA), porphobilinogen (PBG), uroporphyrinogen III (URO III), Mg-protoporphyrin IX (Mg-proto IX), protoporphyrin IX (Proto IX), protochlorophyll (Pchl), thereby increasing the Chl content. Under salinity-alkalinity stress, exogenous GABA increased ALA content, but reduced the contents of Glu, PBG, URO III, Mg-proto IX, Proto IX, Pchl, and Chl. However, salinity-alkalinity stress or GABA treated plant genes expression involved in Chl synthesis had no consistent trends with Chl precursor contents. CONCLUSIONS: Exogenous GABA elevated H2O2 may act as a signal molecule, while AsA and GSH function as antioxidants, in GABA-induced salinity-alkalinity tolerance. These factors maintain membrane integrity which was essential for the ordered chlorophyll biosynthesis. Pretreatment with exogenous GABA mitigated salinity-alkalinity stress caused excessive accumulation of Chl and its precursors, to avoid photooxidation injury.

1,25-Vitamin D3 protects against cooking oil fumes-derived PM2.5-induced cell damage through its anti-inflammatory effects in cardiomyocytes.

The functional role of 1,25-vitamin D3 in cooking oil fumes (COFs)-derived PM2.5-induced cell damage is largely unexplored. The present study investigated the protective role of 1,25-vitamin D3 against cell injury by possible involvement of JAK/STAT and NF-κB signaling pathways in cardiomyocytes. Cell viability was measured using CCK-8 assay, and cell apoptosis was analyzed by flow cytometry, qRT-PCR and Western blot in cultured rat neonatal cardiomyocytes treated with 1,25-vitamin D3 and COFs-derived PM2.5. Expressions of JAK/STAT and NF-κB signaling pathway were measured by Western blot. The results suggested that treatment with COFs-derived PM2.5 significantly decreased cell viability and increased apoptosis and oxidative stress in cultured rat neonatal cardiomyocytes. 1,25-vitamin D3 pretreatment alleviated the cell injury by increasing cell viability and decreasing apoptosis in the cardiomyocytes. 1,25-vitamin D3 pretreatment also decreased the ROS level and inflammation in the cardiomyocytes. Furthermore, 1,25-vitamin D3 pretreatment alleviated COFs-derived PM2.5-evoked elevation of JAK/STAT and NF-κB signaling pathways. Our study showed that 1,25-vitamin D3 pretreatment protected cardiomyocytes from COFs-derived PM2.5-induced injury by decreasing ROS, apoptosis and inflammation level via activations of the JAK/STAT and NF-κB signaling pathways.

A comparison of six clock-drawing test scoring methods in a nursing home.

BACKGROUND: Clock-drawing test (CDT) is widely used but lack of a suitable scoring method. AIMS: To compare the validity of six common CDT scoring methods and to find out the best one. METHODS: The drawing CDT was administered in a Chinese nursing-home inhabitants living on the mainland including 110 dementia, 118 MCI (mild cognitive impairment), and 133 random normal. We calculated the sensitivity and specificity of six scoring methods and applied the receiver-operating characteristic (ROC) curve statistic, including determining the area under the curve (AUC). RESULTS: (1) All six CDT scoring methods had a value of sensitivity higher than 80% and a specificity of 60% except Jouk and Tuokko. Freund got the highest sensitivity (92.73%) of that five for the testing of dementia and high sensitivity (82.20%) for MCI with an acceptable specificity (70.68%). (2) The AUC (area under the ROC curve) of all six CDT methods was over 0.8 for dementia, and for MCI, only Jouk and Tuokko were lower than 0.8. Mendez had the largest AUC of 0.872 for MCI, which closely followed by Freund with 0.859. (3) Freund predicted dementia best but had no significant difference (p > 0.05); it only had significant difference with Jouk and Tuokko (p < 0.001) and the method in MoCA (p < 0.05) for both MCI and cognitive impairment. CONCLUSIONS: Our study suggests that Freund scoring method could be the best one among the six evaluated scoring methods within our setting.

Estimation of diagnostic performance of dementia screening tests: Mini-Mental State Examination, Mini-Cog, Clock Drawing test and Ascertain Dementia 8 questionnaire.

OBJECTIVE: Dementia is one of the leading causes of dependence in the elderly. This study was conducted to estimate diagnostic performance of dementia screening tests including Mini-Mental State Examination (MMSE), Mini-Cog, Clock Drawing Test (CDT) and Ascertain Dementia 8 questionnaire (AD8) by Bayesian models. METHOD: A total of 2015 participants aged 65 years or more in eastern China were enrolled. The four screening tests were administered and scored by specifically trained psychiatrists. The prior information of sensitivity and specificity of every screening test was updated via Bayes' theorem to a posterior distribution. Then the results were compared with the estimation based on National Institute of Aging-Alzheimer's Association criteria (NIA-AA). RESULTS: The diagnostic characteristics of Mini-Cog, including sensitivity, specificity, PPV, NPV, especially the Youden index, performed well, even better than the combinations of several screening tests. CONCLUSION: The Mini-Cog with excellent screening characteristics, spending less time, could be considered to be used as a screening test to help to screen patients with cognitive impairment or dementia early. And Bayesian method was shown to be a suitable tool for evaluating dementia screening tests. CONCLUSION: The Mini-Cog with excellent screening characteristics, spending less time, could be considered to be used as a screening test to help to screen patients with cognitive impairment or dementia early. And Bayesian method was shown to be a suitable tool for evaluating dementia screening tests.

[Analysis of the relevance of age and toe out angle of normal adults' gait].

Due to the decline of motor ability and the impact of the diseases, abnormalities in gait is common in the elderly population, which will raise the risk of fall and cause serious injury. This study focuses on the analysis of the gait kinematics parameters of normal adults' gait, aiming to investigate the characteristics of gait parameters in different age groups and to explore the role of gait parameters in motor function assessment and clinical diagnosis. Based on the gait data gained by electronic walkway, the relationship among the toe out angles and their correlation with age and gender etc. were quantitatively analyzed. The results show that most normal subjects walk with positive toe out angles, and the angles increase with age. Such changes are slow in the young and middle age groups. However, the elevations of the left out toe angle and the angles between the feet are statistically significant after entering elder age ( >60 years). The results also suggest that the angle between the feet is a kind of practical gait parameter for varying applications. This study concludes that feet angle analysis is potential to provide a convenient and quantitative tool for the assessment of lower limb motor ability and the diagnosis of knee joint diseases.

Prevalence of dementia, cognitive status and associated risk factors among elderly of Zhejiang province, China in 2014.

BACKGROUND: the prevalence of dementia in China has risen dramatically in recent decades, but it is not well understood the status in the elderly population in Zhejiang province, eastern China. METHODS: a cross-sectional survey was conducted in four communities across 12 counties in Zhejiang province from May to November 2014. Recruitment included 2,015 subjects aged 65 or older. Trained assessors performed assessments and interviews and collected information. Dementia was diagnosed according to the NIA-AA criteria in 2011. RESULTS: the age-gender-standardised prevalence rates of dementia, Alzheimer's disease and vascular dementia were 13.0, 6.9 and 0.5%, respectively. There were significant increasing trends of rates over ages. Elderly, low educational level, heavy smoking, heavy alcohol consumption, diabetes and stroke were associated with dementia; tea consumption was associated with low prevalence of Alzheimer's disease and severe cognitive impairment. CONCLUSIONS: dementia and cognitive impairment were relatively high among the elderly in Zhejiang province; more attention and population-based strategies are needed.

[Real-time Gait Training System with Embedded Functional Electrical Stimulation].

To solve the problem that mostly gait analysis is independent from the treatment, this work proposes a system that integrates the functions of gait training and assessment for foot drop treatment. The system uses a set of sensors to collect gait parameters and designes multi-mode functional electrical stimulators as actuator. Body area network technology is introduced to coordinate the data communication and execution of the sensors and stimulators, synchronize the gait analysis and foot drop treatment. Bluetooth 4.0 is applied to low the power consumption of the system. The system realizes the synchronization of treatment and gait analysis. It is able to acquire and analyze the dynamic parameters of ankle, knee and hip in real-time, and treat patients by guiding functional electrical stimulation delivery to the specific body locations of patients.

The casual relationship between autoimmune diseases and multiple myeloma: a Mendelian randomization study.

Observational studies showed possible associations between systemic lupus erythematosus and multiple myeloma. However, whether there is a casual relationship between different types of autoimmune diseases (type 1 diabetes mellitus, rheumatoid arthritis, systemic lupus erythematosus, psoriasis, multiple sclerosis, primary sclerosing cholangitis, primary biliary cirrhosis, and juvenile idiopathic arthritis) and multiple myeloma (MM) is not well known. We performed a two-sample Mendelian randomization (MR) study to estimate the casual relationship. Summary-level data of autoimmune diseases were gained from published genome-wide association studies while data of MM was obtained from UKBiobank. The Inverse-Variance Weighted (IVW) method was used as the primary analysis method to interpret the study results, with MR-Egger and weighted median as complementary methods of analysis. There is causal relationship between primary sclerosing cholangitis [OR = 1.00015, 95% CI 1.000048-1.000254, P = 0.004] and MM. Nevertheless, no similar causal relationship was found between the remaining seven autoimmune diseases and MM. Considering the important role of age at recruitment and body mass index (BMI) in MM, we excluded these relevant instrument variables, and similar results were obtained. The accuracy and robustness of these findings were confirmed by sensitivity tests. Overall, MR analysis suggests that genetic liability to primary sclerosing cholangitis could be causally related to the increasing risk of MM. This finding may serve as a guide for clinical attention to patients with autoimmune diseases and their early screening for MM.

Comparison of the effects of using feedback devices for training or simulated cardiopulmonary arrest.

BACKGROUND: High-quality chest compression is essential for successful cardiac arrest resuscitation. High-quality cardiopulmonary resuscitation (CPR) can effectively improve the survival rate of patients with cardiopulmonary arrest. However, bystanders untrained in cardiopulmonary resuscitation may provide inadequate chest compressions. Previous studies have shown that the use of feedback devices in training alone or in simulated cardiopulmonary arrest alone can improve cardiopulmonary resuscitation. This study aims to determine whether using an audiovisual feedback (AVF) device during CPR training or a simulated cardiopulmonary arrest (CA) scenario would be more effective in improving the quality of chest compressions (CC). METHODS: We use a prospective, randomized, 2 × 2 factorial design trial. A total of 160 participants from Wuhan University and senior clinical medicine undergraduates who had not participated in any CPR training before and had no actual CPR experience are recruited. Each participant is randomized to 1 of 4 permutations, including AVF device vs. no AVF device during CPR training and AVF device vs. no AVF device during simulated CA. Main outcomes and measures are the depth, the percentage of CCs with correct depth (5-6 cm), the rate of CCs, and the percentage of CCs with the correct rate (100-120 cpm). RESULTS: The use of the AVF device during simulated CA resulted in improved CC quality. In CA without AVF device, the average compression depth and the percentage of adequate depth with AVF device are 5.1 cm, 5.0 cm and 55.5%, 56.3%, respectively, which are higher than those without AVF device (4.5 cm, 4.7 cm and 32.8%, 33.6%). (p = 0.011, p = 0.000, both < 0.05).Compared with CA without AVF device, the average compression rate and the percentage of adequate rate with AVF device are 112.3 cpm, 111.2 cpm and 79.4%, 83.1%, respectively. The average compression rate and the percentage of adequate rate without using the AVF device are 112.4 cpm, 110.3 cpm and 71.5%, 68.5%, respectively. (p = 0.567 > 0.05, p = 0.017 < 0.05)Although the average compression rate in group D is slightly lower than that in group C, the percentage of suitable frequency with the feedback device is still higher than that without AVF device. CONCLUSION: Using a feedback device during simulated cardiopulmonary arrest is more effective in improving cardiopulmonary resuscitation than during training.