Synergistic effect and molecular mechanism of PVA and UM171 in ex vivo expansion of primitive hematopoietic stem cells.

Umbilical cord blood (UCB) is a valuable source of hematopoietic stem cells (HSCs) used for transplantation; the number of cells in a single UCB is too small to quickly establish bone marrow (BM) implantation, and ex vivo expansion of HSCs has the potential to overcome this limitation. The purpose of this study is to explore the culture conditions conducive to the maintenance and expansion of hematopoietic stem and progenitor cells (HSPCs) and long-term hematopoietic stem cells (LT-HSCs) derived from human umbilical cord blood, compare the different effects of albumin (HSA) and polyvinyl alcohol (PVA), optimize the culture system using UM171 and investigate the molecular mechanism of PVA and UM171 promoting the expansion of primitive hematopoietic stem cells. CD34+ cells were purified from UCB using MacsCD34 beads, and then cultured in serum-free medium supplemented with cytokines for 12 days, with PVA or UM171 added according to experimental requirements; the relative percentage of different HSCs subsets after culture were detected by flow cytometry; CFU Assay Setup for detecting the multilineage differentiation potential of HSCs; RT-PCR detection of gene expression levels; reactive oxygen detection assessment of intracellular ROS levels. (1) The conditions of 20 ng/mlSCF, 100 ng/mlTPO, and 5% oxygen concentration are conducive to the maintenance of LT-HSCs. (2) Compared with HSA, PVA significantly increased the proportion of HSPCs and LT-HSCs, as well as dramatically promoted the expression of antioxidant enzymes and reduced the production of reactive oxygen species (ROS). (3) After adding UM171 to PVA-based medium, the proportion of HSPCs and LT-HSCs further increased, and downstream genes of Notch and Wnt pathways were selectively activated. (1) PVA may inhibit ROS production by upregulating the expression of antioxidant enzymes, which is beneficial for maintaining stemness and inhibiting differentiation of HSCs. (2) The antioxidant properties of PVA can delay differentiation, while UM171 can promote self-renewal by regulating the stem cell pathway, and the combination of them is beneficial for the maintenance and expansion of HSCs in vitro.

Systematic pole-zero sorting method for neuro-TF modeling of electromagnetic response.

Neuro-transfer functions (neuro-TF) modeling method has been developed as one of the popular methods for parametric modeling of electromagnetic (EM) filter responses. The discontinuity issue of zero and pole data caused by extraction using vector fitting w.r.t. geometrical parameters change affects the neuro-TF training process and limits its modeling accuracy. This issue is addressed by this paper which proposes a novel systematic pole-zero sorting method for neuro-TF parametric modeling. The proposed method can obtain continuous pole-zero data which change much more smooth w.r.t. geometrical parameters change than the existing neuro-TF method, especially solves the difficulty of disorder of positive and negative values due to small values. The proposed systematic sorting method can substantially improve the modeling accuracy during the establishment and training of neuro-TF model over the existing neuro-TF method without systematic sorting.

Baicalein attenuates oxidative damage in mice haematopoietic cells through regulation of PDGFRß.

Platelet-derived growth factor receptor ß (PDGFRß) plays a crucial role in murine haematopoiesis. Baicalein (BAI), a naturally occurring flavonoid, can alleviate disease damage through anti-oxidative, anti-apoptotic, and anti-inflammatory mechanisms. However, whether BAI attenuates oxidative damage in murine haematopoietic cells by PDGFRß remains unexplored. In this study, we utilized a tert-butyl hydroperoxide (TBHP)-induced BaF3 cell injury model and an ionising radiation (IR)-induced mice injury model to investigate the impact of the presence or absence of PDGFRß on the pharmacological effects of BAI. In addition, the BAI-PDGFRß interaction was characterized by molecular docking and dynamics simulations. The results show that a specific concentration of BAI led to increased cell viability, reduced reactive oxygen species (ROS) content, upregulated nuclear factor erythroid 2-related factor 2 (NRF2) expression, and its downstream target genes heme oxygenase 1 (HO-1) and NAD(P)H Quinone Dehydrogenase 1 (NQO1), and activated protein kinase B (AKT) pathway in cells expressing PDGFRß plasmid and experiencing damage. Similarly, BAI elevated lineage-Sca1+cKIT+ (LSK) cell proportion, promoted haematopoietic restoration, enhanced NRF2-mediated antioxidant response in PDGFRß+/+ mice. However, despite BAI usage, PDGFRß knockout mice (PDGFRß-/-) showed lower LSK proportion and less antioxidant capacity than the total body irradiation (TBI) group. Furthermore, we demonstrated an interaction between BAI and PDGFRß at the molecular level. Collectively, our results indicate that BAI attenuates oxidative stress injury and helps promote haematopoietic cell recovery through regulation of PDGFRß.

Spermidine regulates wheat grain weight at high planting density by promoting the synthesis of sucrose and starch in inferior grains.

Increasing density is an effective way to enhance wheat (Triticum aestivum L.) yield under limited cultivated areas. However, the physiological mechanisms underlying the reduction in grain weight when density increased are still unclear. Three field experiments were conducted during the 2014-2019 growing seasons to explore the physiological mechanisms by which polyamines affect grain weight formation. The results showed that when wheat planting density exceeded 450 × 104 seedlings ha-1 and 525 × 104 seedlings ha-1, wheat yield tended to decrease. Compared to moderate density (DM, 450 × 104 seedlings ha-1), the filling rate of inferior grains was reduced before 25 days after anthesis (DAA) and the active filling period was shortened by 6.4%-7.4% under high density (DH, 600 × 104 seedlings ha-1), resulting in a loss of 1000-grain weight by 5.4%-8.1%. DH significantly reduced sucrose and starch content in inferior grains at the filling stage. Meanwhile, DH inhibited the activity of key enzymes involved in polyamine synthesis [SAMDC (EC 4.1.1.50) and SpdSy (EC 2.5.1.16)] and induced the activity of ethylene (ETH) precursor synthase, resulting in a significant decrease in endogenous spermidine (Spd) content in inferior grains, but a significant increase in ETH release rate. Post-flowering application of exogenous Spd increased the accumulation of sucrose and starch in the inferior grains and positively regulated the filling and grain weight of the inferior grains, whereas exogenous ETH had a negative effect. Overall, Spd may affect wheat grain weight at high planting density by promoting the synthesis of sucrose and starch in inferior grains.

Evaluation of preoperative difficult airway prediction methods for adult patients without obvious airway abnormalities: a systematic review and meta-analysis.

BACKGROUND: This systematic review aims to assist clinical decision-making in selecting appropriate preoperative prediction methods for difficult tracheal intubation by identifying and synthesizing literature on these methods in adult patients undergoing all types of surgery. METHODS: A systematic review and meta-analysis were conducted following PRISMA guidelines. Comprehensive electronic searches across multiple databases were completed on March 28, 2023. Two researchers independently screened, selected studies, and extracted data. A total of 227 articles representing 526 studies were included and evaluated for bias using the QUADAS-2 tool. Meta-Disc software computed pooled sensitivity (SEN), specificity (SPC), positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR). Heterogeneity was assessed using the Spearman correlation coefficient, Cochran's-Q, and I2 index, with meta-regression exploring sources of heterogeneity. Publication bias was evaluated using Deeks' funnel plot. RESULTS: Out of 2906 articles retrieved, 227 met the inclusion criteria, encompassing a total of 686,089 patients. The review examined 11 methods for predicting difficult tracheal intubation, categorized into physical examination, multivariate scoring system, and imaging test. The modified Mallampati test (MMT) showed a SEN of 0.39 and SPC of 0.86, while the thyromental distance (TMD) had a SEN of 0.38 and SPC of 0.83. The upper lip bite test (ULBT) presented a SEN of 0.52 and SPC of 0.84. Multivariate scoring systems like LEMON and Wilson's risk score demonstrated moderate sensitivity and specificity. Imaging tests, particularly ultrasound-based methods such as the distance from the skin to the epiglottis (US-DSE), exhibited higher sensitivity (0.80) and specificity (0.77). Significant heterogeneity was identified across studies, influenced by factors such as sample size and study design. CONCLUSION: No single preoperative prediction method shows clear superiority for predicting difficult tracheal intubation. The evidence supports a combined approach using multiple methods tailored to specific patient demographics and clinical contexts. Future research should focus on integrating advanced technologies like artificial intelligence and deep learning to improve predictive models. Standardizing testing procedures and establishing clear cut-off values are essential for enhancing prediction reliability and accuracy. Implementing a multi-modal predictive approach may reduce unanticipated difficult intubations, improving patient safety and outcomes.

Association between inflammatory bowel disease and frailty: a two-sample Mendelian randomization study.

BACKGROUND: An association has been identified between inflammatory bowel disease (IBD) and frailty; however, the causal nature of this connection remains uncertain. We consequently conducted a two-sample Mendelian randomization (MR) analysis to explore this particular association. METHODS: We acquired distinct datasets for inflammatory bowel disease (IBD), Crohn's disease (CD), ulcerative colitis (UC), and frailty from the published genome-wide association studies (GWAS) database, meticulously selecting instrumental variables (IVs). Subsequently, we employed a bidirection MR to examine the causal relationship between IBD (including CD and UC) and frailty. We utilized statistical methods, with a primary emphasis on inverse-variance weighted (IVW), accompanied by a series of sensitivity analyses to confirm heterogeneity and pleiotropy influenced the outcomes of the MR. RESULTS: We found positive causal effects of genetically increased frailty risk on IBD (OR: 1.015, 95% CI 1.005-1.025, P = 0.004). Furthermore, when scrutinizing specific IBD subtypes, both Crohn's disease (CD) and ulcerative colitis (UC) demonstrated an increased predisposition to frailty (OR: 1.018, 95% CI 1.01-1.027, P < 0.05) and (OR = 1.016, 95% CI 1.005-1.027, P < 0.05). Nevertheless, despite the consistent trends observed in the weighted median and MR-Egger regression analyses for both conditions, statistical significance remained elusive. Notably, the results of the inverse MR analysis did not establish an association between frailty and an elevated risk of IBD development. CONCLUSIONS: Our research indicates that IBD, encompassing both CD and UC, may augment the propensity for frailty. Clinical practitioners must prioritize early frailty assessment in individuals afflicted with inflammatory bowel disease, inclusive of Crohn's disease and ulcerative colitis, facilitating proactive measures and timely interventions. However, our findings do not provide evidence supporting a causal effect of frailty on IBD (including CD and UC). Consequently, further studies are essential to explore the intricate mechanisms that clarify the effect of frailty on IBD.

Determination of carboxylesterase by fluorescence probe to guide detection of carbamate pesticide.

A carboxylesterase fluorescent probe (Probe 1) was developed for determination of carboxylesterase to guide detection of carbamate pesticide. The probe uses benzothiazole as fluorescence group and phenyldimethyl carbamate as recognition group. The solution of the fluorescent probe gradually changes from light blue to dark blue as the concentration of carbamate pesticides increases. The concentration of carbamate pesticides can be quickly calculated according to the colour of the probe solution through Get Color software on a smartphone. It showed that Probe 1 can be used as a rapid detection tool to achieve rapid detection of carbamate pesticides in juice samples without professional personnel and equipment. Furthermore, the probe has been successfully used to detect carbamate pesticides in fruit juice and vegetable juice.

Antimicrobial resistance characteristics and phylogenetic relationships of pleuromutilin-resistant Enterococcus isolates from different environmental samples along a laying hen production chain.

Antimicrobial resistance in the laying hen production industry has become a serious public health problem. The antimicrobial resistance and phylogenetic relationships of the common conditional pathogen Enterococcus along the laying hen production chain have not been systematically clarified. 105 Enterococcus isolates were obtained from 115 environmental samples (air, dust, feces, flies, sewage, and soil) collected along the laying hen production chain (breeding chicken, chick, young chicken, and commercial laying hen). These Enterococcus isolates exhibited resistance to some clinically relevant antibiotics, such as tetracycline (92.4%), streptomycin (92.4%), and erythromycin (91.4%), and all strains had multidrug resistance phenotypes. Whole genome sequencing characterized 29 acquired antibiotic resistance genes (ARGs) that conferred resistance to 11 classes of antibiotics in 51 pleuromutilin-resistant Enterococcus isolates, and lsa(E), which mediates resistance to pleuromutilins, always co-occurred with lnu(B). Alignments with the Mobile Genetic Elements database identified four transposons (Tn554, Tn558, Tn6261, and Tn6674) with several ARGs (erm(A), ant(9)-la, fex(A), and optrA) that mediated resistance to many clinically important antibiotics. Moreover, we identified two new transposons that carried ARGs in the Tn554 family designated as Tn7508 and Tn7492. A complementary approach based on conventional multi-locus sequence typing and whole genome single nucleotide polymorphism analysis showed that phylogenetically related pleuromutilin-resistant Enterococcus isolates were widely distributed in various environments on different production farms. Our results indicate that environmental contamination by antimicrobial-resistant Enterococcus requires greater attention, and they highlight the risk of pleuromutilin-resistant Enterococcus and ARGs disseminating along the laying hen production chain, thereby warranting effective disinfection.

Utility of the capability, opportunity, and motivation behaviour (COM-B) model in explaining the negative association between pre-pregnancy body mass index and exclusive breastfeeding at six weeks postpartum.

The mechanisms underlying the negative associations between pre-pregnancy body mass index (BMI) and exclusive breastfeeding remain poorly understood. Thus, the study aimed to determine whether the negative associations between high pre-pregnancy BMI and exclusive breastfeeding at six weeks postpartum are mediated by components of the capability, opportunity, and motivation behaviour (COM-B) model. In this prospective observational study, we assigned 360 primiparous women to a pre-pregnancy overweight/obese group (n = 180) and a normal-BMI group (n = 180). A structural equation model was designed to study how capabilities (onset of lactogenesis II, perceived milk supply, breastfeeding knowledge, and postpartum depression), opportunities (pro-breastfeeding hospital practices, social influence, social support), and motivations (breastfeeding intention, breastfeeding self-efficacy, and attitudes towards breastfeeding) affected exclusive breastfeeding at six weeks postpartum in groups of women with different pre-pregnancy BMIs. In all, 342 participants (95.0%) possessed complete data. Women with high pre-pregnancy BMI were less likely to exclusively breastfeed at six weeks postpartum than women with a normal BMI were. We observed a significant negative direct effect of high pre-pregnancy BMI on exclusive breastfeeding at six weeks postpartum and a significantly negative indirect effect of high pre-pregnancy BMI via the explanatory mediating variables of capabilities (onset of lactogenesis II, perceived milk supply, and breastfeeding knowledge) and motivations (breastfeeding self-efficacy) on exclusive breastfeeding at six weeks postpartum. Our findings support certain capabilities (onset of lactogenesis II, perceived milk supply, and breastfeeding knowledge) and motivations (breastfeeding self-efficacy), partially explaining the negative association between high pre-pregnancy BMI and exclusive breastfeeding outcome. We suggest that interventions aimed at promoting exclusive breastfeeding among women with high pre-pregnancy BMI should address the capacity and motivation factors specific to this population.

Decision tool of medical endoscope maintenance service in Chinese hospitals: a conjoint analysis.

BACKGROUND: Medical devices are instruments, apparatus, appliances, software, implants, reagents, materials or other articles that are intended for use in the treatment or diagnosis of disease or injury in humans. Concerning medical endoscope devices, which enable doctors to observe and manipulate the area under examination through a puncture hole in the body cavity or organ, hospitals predominantly consider the quality and cost of maintenance services when making their selection. The effective and efficient provision of maintenance services plays a crucial role in ensuring cost-effective and high-quality management of medical devices. In this study, we have developed an innovative decision tool that analyzed key factors impacting the choice of medical devices' maintenance service. This tool assists hospitals in evaluating and selecting appropriate maintenance services for medical device, specifically endoscopy devices. Moreover, it also serves as a valuable resource for manufacturers and suppliers to enhance their after-sales service offerings. METHODS: A cross-sectional survey was undertaken in 50 Chinese hospitals, including primary and tertiary hospitals. Moreover, 56 medical staff and 65 medical engineers were recruited from 50 Chinese hospitals to participate the survey. A comprehensive set of factors were defined and investigated. Conjoint analysis and orthogonal design were used for survey design and statistical analysis. RESULTS: Factors importance and utility values of decision-making factors were analyzed at the aggregate, occupation, and medical institution levels. (1) At the aggregate level, the most critical factor is "maintenance response" and the least important one is "maintenance efficiency". (2) At the occupation level, medical staff paid more attention to "maintenance response" while medical engineers paid more attention to "maintenance quality". (3) At the medical institution level, Primary hospitals paid more attention to "maintenance price", while tertiary hospitals paid more attention to "maintenance quality". CONCLUSIONS: In general, this study provides a more scientific decision-making tool to both hospitals in choosing maintenance service for medical device such as endoscopy, and it also helps manufacturers and suppliers improve the after-sales service.

Association Between Social Networking Site Use Intensity and Depression Among Chinese Pregnant Women: Cross-sectional Study.

BACKGROUND: Despite extensive debates about the mental health impacts of the use of social networking sites (SNSs), including WeChat, the association and mechanisms between social interaction of WeChat use intensity and antenatal depression are unclear. OBJECTIVE: We aimed to test the mediating roles of upward social comparison on social interaction of WeChat and rumination in the association between social interaction of WeChat use intensity and antenatal depression. METHODS: A cross-sectional survey was conducted in four hospitals with the self-reported measures of social interaction of WeChat use intensity, upward social comparison on social interaction of WeChat, rumination, antenatal depression, and control variables. The mediation analysis was performed through Model 6 from the PROCESS macro 4.0 in SPSS 26. RESULTS: Results from 2661 participants showed that antenatal depression was unrelated to social interaction of WeChat use intensity (P=.54), but was significantly positively related to the attitude toward social interaction of WeChat (P=.01). The direct effect of attitude toward social interaction of WeChat use on antenatal depression was not statistically significant (ß=-.03, P=.05). The results supported an indirect relationship between attitude toward social interaction of WeChat use and antenatal depression via (1) upward social comparison on social interaction of WeChat (indirect effect value=0.04, 95% CI 0.03 to 0.06); (2) rumination (indirect effect value=-0.02, 95% CI -0.04 to -0.01); and (3) upward social comparison on social interaction of WeChat and rumination in sequence (indirect effect value=0.07, 95% CI 0.06 to 0.08). CONCLUSIONS: Our findings highlight the necessity of focusing on attitudes toward SNS use, and the importance of upward social comparison and rumination in understanding the effect of SNS use on antenatal depression.

Exploring the abundance and influencing factors of antimicrobial resistance genes in manure plasmidome from swine farms.

Plasmids play a critical role in the dissemination of antimicrobial resistance genes (ARGs), however, a systematical understanding of ARGs originated from plasmids in swine production is currently lacking. Herein, quantitative polymerase chain reaction was applied to determine the prevalence of ten ARGs and the class1 integron gene intI1 of plasmid source in swine manure from 44 farms in Sichuan, Hubei and Hebei provinces, China. All assayed ARGs were observed in plasmid DNA samples, and the average absolute abundance of aac(6')-Ib-cr, blaNDM, blaCTX-M, optrA, ermB, floR, mcr-1, qnrS, tetM, sul1 and intI1 were 7.09, 2.90, 4.67, 6.62, 7.55, 7.14, 4.08, 4.85, 7.16, 7.11 and 8.07 of 10 log copies/gram, respectively. IntI1 showed a high correlation (r > 0.8, P < 0.01) with the abundance of aac(6')-Ib-cr and sul1 in swine manure. Moreover, the farm scale (i.e., herd population) and geographical location were not found to be critical factors influencing the absolute abundance of ARGs of plasmid DNA in swine farms. However, the concentrations of florfenicol, Cu, Zn, Fe, total phosphorus (TP) and total potassium (TK) demonstrated a significant correlation with the abundance of several ARGs. Particularly, Cu and Zn had high correlations with optrA and blaCTX-M, respectively. Our results demonstrated that antibiotics, heavy metals and environmental nutrients are likely jointly contributing to the long-term persistence of ARGs in swine production. This study provides insights into the abundance and influencing factors of ARGs from swine manure, which is of significance for assessing and reducing the public health risks in livestock production.

Glucocorticoids suppressed osteoblast differentiation by decreasing Sema3A expression via the PIK3/Akt pathway.

Glucocorticoids(GCs) are extensively used to treat inflammatory and autoimmune diseases. Excessive prolonged exposure to glucocorticoids is associated with an increased risk of osteoporosis. The inhibition of osteoblast differentiation by GCs is suggested as a major cause for GCs-induced osteoporosis (GIO). However, the precise mechanism underlying the role of GCs in osteoblasts differentiation is not fully elucidated. Semaphorin 3A (Sema3A), a secreted member of the Semaphorin family, enhances bone formation and promotes fracture healing, which is known to increase osteoblastic differentiation and stimulate osteogenesis in bone metabolism. Here, the present study explored the effect of Sema3A in osteoblast differentiation using dexamethasone (Dex) treatment of bone marrow stromal cells (BMSCs). Dex treatment decreased Sema3A expression in BMSCs in a dose-dependent manner. Moreover, Dex stimulation suppressed the differentiation of osteoblasts by reducing alkaline phosphatase (ALP) activity, osteoblastic marker genes expression and mineralization, but all of these effects were ameliorated by exogenous recombinant Sema3A administration. Furthermore, exogenous Sema3A administration reversed the Dex-mediated decrease in nuclear accumulation of ß-catenin and ß-catenin activity in BMSCs. Meanwhile, Dex was capable of simultaneously suppressing the phosphorylation of protein kinase B(Akt) and the expression level of Sema3A in BMSCs. These changes were significantly abolished by the PI3K/Akt agonist. These results suggest that Dex inhibits osteoblast differentiation by suppressing Sema3A expression via the PI3K/Akt pathway. These data provide new insights into the molecular mechanisms of Dex-induced osteoblast differentiation inhibition.

Establishment of a medical device adverse event management system for hospitals.

BACKGROUND: The management of medical device adverse event (MDAE) is one of the most important aspects of improving medical quality and safety management. Nonetheless, hospitals still lack standardized and unified initiatives to improve MDAE management. METHODS: This study, thus, established a MDAE monitoring system on May 1 in 2011 for suspected adverse events and designed a hospital-based dynamic warning system, aiming to standardize the process of MDAE handling and provide real-time monitoring for MDAEs in a hospital. This system was used in the First Affiliated Hospital of Zhejiang University School of Medicine. Numbers and the compound growth rate of MDAE reports from 2010 to 2020 were compared to test the effectiveness of the MDAE monitoring system. Numbers of MDAE reported to the National Adverse Event Monitoring System were also compared over 2013 to 2020, due to the loss of data before 2013 after shutdown of the old system. Efficacy and usability of the hospital-based dynamic warning system was then verified by analyzing risk and warning levels of MDAEs in 2020. Descriptive statistics was used for data analysis in this study. RESULTS: Results showed that the compound annual growth rates of MDAE reports and those submitted to the National Adverse Event Monitoring System from 2013 to 2020 were 35.0% and 31.5%, respectively. A standardized management of MDAE with full participant, timely response and effective feedback was formed in the hospital by establishment of the MDAE system. CONCLUSIONS: This system effectively improved the monitoring level of MDAEs, helping to improve early detection, early warning, and early intervention of risk of medical device. This study may provide suggestions for medical institutions to establish a MDAE monitoring system, and may promote development of medical quality and safety management for hospitals to some extent.

A novel fluorescence probe for the detection of water content in organic solvents and the distinction between deuterated and nondeuterated reagents.

A novel D-π-A type fluorescent probe (probe 1) was developed for water content detection in organic solvents. By analyzing the relationship between fluorescence and water content, the probe was successfully applied to determine trace water content in tetrahydrofuran, ethyl acetate, 2-butanone, acetone, dimethylformamide, and acetonitrile. High water content in THF and ethyl acetate was associated with a gradual colour change from yellowish green to earthy yellow. The red/green value had a linear relationship with the water content in THF and ethyl acetate. There was a linear relationship between the red/blue value and water content in 2-butanone and acetone. Furthermore, probe 1 could be used for human serum albumin detection. Unexpectedly, probe 1 had a different colour response in deuterated and nondeuterated solvents, and had different fluorescence intensity and fluorescence emission wavelength. Probe 1 is rare tool that can distinguish between deuterated and nondeuterated reagents.

Variations in Hydraulic Conductivity of Montmorillonite in Dual-Cation Electrolyte Solutions.

The hydraulic conductivity of Na-montmorillonite in dual-cation solutions of Na+ and Mn+ (Mn+ = K+, Ca2+, Zn2+ and Al3+) with a constant ionic strength of 0.1 mol/L was determined. The focus of this study was on the influence of Mn+ on the grain-size distribution of montmorillonite and hence its hydraulic conductivity. All the tested cations showed a high affinity towards montmorillonite, and the high valency favored the exchange between Mn+ and Na+. The hydraulic conductivity of montmorillonite increased to the maxima and then decreased in a left-skewed log-normal shape as the cation exchange progressed. The grain size of montmorillonite concurrently decreased monotonically with the cation exchange. The XRD patterns of montmorillonite confirmed the occurrence of demixing of Na+ and K+ in the interlayers. It is proposed that the rearrangement and reaggregation of grains during cation exchange occurred, leading to variations in the hydraulic conductivity of montmorillonite.

Current Status of MicroRNAs that Target the Wnt Signaling Pathway in Regulation of Osteogenesis and Bone Metabolism: A Review.

The directional differentiation of bone mesenchymal stem cells (BMSCs) is regulated by a variety of transcription factors and intracellular signaling pathways. In the past, it was thought that the directional differentiation of BMSCs was related to transforming growth factors, such as bone morphogenetic protein (BMP) and MAPK pathway. However, in recent years, some scholars have pointed out that the Wnt signaling pathway, which is a necessary complex network of protein interactions for biological growth and development, takes a significant role in this process and plays a major part in regulating the development of osteoblasts by exerting signal transduction into cells. Also, they have proved the Wnt protein therapeutic truly have positive effects on the viability and osteogenic capacity of bone graft. Recent studies have shown that microRNAs (miRNAs) play an important regulatory role in this process. MiRNAs such as miRNA-218, miRNA-335, miRNA-29, microRNA-30 and other miRNAs exert negative or positive effects on some crucial molecules in the Wnt/ß-catenin pathway, which in turn affect bone metabolism and osteopathy. Thus, miRNAs have been suggested as therapeutic targets for some metabolic bone diseases. This article aims to provide an update on the current status of microRNAs that target the Wnt signaling pathway in the regulation of osteogenesis and bone metabolism and includes a discussion of future areas of research, which can be a theoretical basis for bone metabolism-related diseases.

Fault Diagnosis of Permanent Magnet Synchronous Motor Based on Stacked Denoising Autoencoder.

As a complex field-circuit coupling system comprised of electric, magnetic and thermal machines, the permanent magnet synchronous motor of the electric vehicle has various operating conditions and complicated condition environment. There are various forms of failure, and the signs of failure are crossed or overlapped. Randomness, secondary, concurrency and communication characteristics make it difficult to diagnose faults. Meanwhile, the common intelligent diagnosis methods have low accuracy, poor generalization ability and difficulty in processing high-dimensional data. This paper proposes a method of fault feature extraction for motor based on the principle of stacked denoising autoencoder (SDAE) combined with the support vector machine (SVM) classifier. First, the motor signals collected from the experiment were processed, and the input data were randomly damaged by adding noise. Furthermore, according to the experimental results, the network structure of stacked denoising autoencoder was constructed, the optimal learning rate, noise reduction coefficient and the other network parameters were set. Finally, the trained network was used to verify the test samples. Compared with the traditional fault extraction method and single autoencoder method, this method has the advantages of better accuracy, strong generalization ability and easy-to-deal-with high-dimensional data features.

DEK terminates diapause by activation of quiescent cells in the crustacean Artemia.

To cope with harsh environments, the Artemia shrimp produces gastrula embryos in diapause, a state of obligate dormancy, having cellular quiescence and suppressed metabolism. The mechanism behind these cellular events remains largely unknown. Here, we study the regulation of cell quiescence using diapause embryos of Artemia We found that Artemia DEK (Ar-DEK), a nuclear factor protein, was down-regulated in the quiescent cells of diapause embryos and enriched in the activated cells of post-diapause embryos. Knockdown of Ar-DEK induced the production of diapause embryos whereas the control Artemia released free-swimming nuaplii. Our results indicate that Ar-DEK correlated with the termination of cellular quiescence via the increase in euchromatin and decrease in heterochromatin. The phenomena of quiescence have many implications beyond shrimp ecology. In cancer cells, for example, knockdown of DEK also induced a short period of cellular quiescence and increased resistance to environmental stress in MCF-7 and MKN45 cancer cell lines. Analysis of RNA sequences in Artemia and in MCF-7 revealed that the Wnt and AURKA signaling pathways were all down-regulated and the p53 signaling pathway was up-regulated upon inhibition of DEK expression. Our results provide insight into the functions of Ar-DEK in the activation of cellular quiescence during diapause formation in Artemia.

Model construction of medical endoscope service evaluation system-based on the analysis of Delphi method.

BACKGROUND: Medical endoscope is widely used in clinical practice for the purpose of diagnosis and treatment, occupying around 5% of the medical device market. Evaluating the true service level of medical endoscope is essential and necessary to improve overall performance of medical diagnosis and treatment, and to maintain competitiveness of endoscope manufacturers, however, such a tool is not available in the market. This study develops an Evaluation Index System (EIS) to assess service level of medical endoscope, and to provide suggestions for improving the service level through the Delphi method. METHODS: Firstly, the possible factors influencing the service level were identified from literature review. In parallel, the Delphi expert method questionnaire was designed and 25 experts were invited to conduct three rounds of questionnaire, to evaluate and rate the possible factors. Finally, we determined the weights associated with the factors, using the analytic hierarchy process (AHP) and percentage method, and developed the service level EIS. RESULTS: The EIS consists of 3 first-level indicators, 24 s-level indicators and 68 third-level indicators. According to the weights computed using AHP, first-level indicators are ranked as post-sale (0.62), in-sale (0.25) and pre-sale (0.13). Through case verification, the medical endoscope brand Olympus had a total score of 4.17, Shanghai Aohua had a total score of 3.71, and Shanghai Chengyun had a total score of 3.28, which matches its market popularity and ranking in terms of market share. The results obtained from the EIS are consistent with the reality. CONCLUSIONS: The EIS established in this study is comprehensive, reliable and reasonable with strong practicality. The EIS can act as a tool for the endoscope users to evaluate potential products and make informed choices. It also provides a measurable basis for endoscope manufacturers and service providers to improve service quality.