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Objective: To extract Astragalus polysaccharides (APS) from Astragalus membranaceus using compound enzymes (including papain, pectinase and cellulase), and to analyze the effect of process conditions on APS extraction. Methods: Orthogonal experiments were conducted to determine the proportion of compound enzymes. The response surface method was used to optimize the conditions of extracting APS with compound enzymes. The optimal process condition was obtained, and the α-glucosidase-inhibiting effect of APS was evaluated by pNPG method. Results: For 5 g of Astragalus herbs, the optimal ratio of papain, pectinase and cellulase were 88000 U, 65000 U and 6000 U, respectively. The optimal extraction condition was as follows: time of 2.82 h, temperature at 60.34 ℃, pH of 5.11, and solid-liquid ratio of 1:34.46 g/mL. The yield of APS under the optimal condition was up to 22.79%±0.14%. The half-inhibition concentration (IC50) of APS for α-glucosidase was 7.42 μg/mL. Conclusion: The yield of APS by compound enzymes is significantly higher than that by single enzymes, and APS can effectively inhibit the activity of α-glucosidase.

Multi-enzyme-assisted laminarin extraction parameters were optimized, and then the prepared laminarin was assessed for inhibition of α-glucosidase activity. The relative proportions of preparative enzymes were investigated to maximize laminarin yield using an orthogonal test design. The effect of enzymatic hydrolysis time, pH, ratio of liquid to material and temperature on laminarin yield were determined using response surface methodology (RSM). Finally, laminarin inhibition of α-glucosidase activity was assessed using an in vitro enzyme inhibition test. Results revealed that the optimal laminarin yield was obtained using a ratio by mass of 10:9:5.5 of cellulase, pectinase and papain, respectively, and an enzymatic hydrolysis time, temperature, pH and ratio of liquid to material of 1.8 h, 49.4 ℃, 6.1 and 59:1 mL/g, respectively. The predicted yield of laminarin under optimal conditions was 18.183%, which resembled the actual laminarin yield of 18.19%±1.04%. Its neutral sugar, acid sugar, protein and sulphate contents were 52.72%, 11.76%, 2.66% and 19.49%, respectively. As laminarin concentration increased from 1 mg/mL to 5 mg/mL, its α-glucosidase inhibition activity increased, with highest inhibition of 79.04%±3.17% and IC50 value of 1.443 mg/mL. This multi-enzyme-assisted extraction procedure generated a high yield of laminarin that exerted clearly demonstrable inhibition of α-glucosidase activity.

ObjectiveRed cell distribution width (RDW) and serum calcium (Ca) levels are predictors of in-hospital mortality in acute myocardial infarction (AMI) patients. However, their sensitivity and specificity are limited. Therefore, this study aimed to determine whether the RDW to Ca ratio (RCR) acquired on admission can be used to predict the in-hospital mortality of AMI patients.MethodsThis retrospective cohort study extracted clinical information from the Medical Information Market for Intensive IV (MIMIC-IV) database on 2,910 AMI patients enrolled via propensity score matching (PSM). Prognostic values were assessed using a multivariate logistic model and three PSM approaches. Analysis was performed based on stratified variables and interactions among sex, age, ethnicity, anemia, renal disease, percutaneous transluminal coronary intervention (PCI), coronary artery bypass grafting (CABG), atrial fibrillation, congestive heart failure, dementia, diabetes, paraplegia, hypertension, cerebrovascular disease, and Sequential Organ Failure Assessment (SOFA) score.ResultsA total of 4,105 ICU-admitted AMI patients were analyzed. The optimal cut-off value of the RCR for in-hospital mortality was 1.685. The PSM was performed to identify 1,455 pairs (2,910) of score-matched patients, with balanced differences exhibited for nearly all variables.The patients’ median age was 72 years (range, 63–82 years) and 60.9% were male. The risk of in-hospital mortality incidence increased with increasing RCR levels. After adjusting for confounders, the risk ratio for the incidence of in-hospital mortality for high RCR was 1.75 [95% confidence interval (CI): 1.60–1.94, P = 0.0113] compared to that associated with low RCR in the PSM cohort. High RCR was also substantially implicated in in-hospital mortality incidence in the weighted cohorts [odds ratio (OR) = 1.76, 95% CI: 1.62–1.94, P = 0.0129]. Assessment of RCR in three groups showed that patients with high RCR also had a higher risk of in-hospital mortality (OR = 3.04; 95% CI, 2.22–4.16; P

BackgroundWith the gradual penetration of network media into various fields of people's life, the relationship between network behavior and the sense of meaning of life is bound to be closer and closer. The purpose of this study is to explore the mediating role of state anxiety between cyber loafing and the sense of meaning of life, and the moderating role of psychological flexibility in this mediating relationship.MethodologyWith 964 undergraduates recruited as subjects three-wave-time-lagged quantitative research design was conducted in China. All participants were required to complete a self-reported electronic questionnaire. Then, the mediating mechanism and moderating effect were explored with utilization of SPSS25.0.ResultsThe results showed that cyberloafing had significant negative correlation with the sense of meaning of life. Our analysis testing the mediating effect showed that state anxiety partially mediated the relationship between cyberloafing and the sense of meaning of life (indirect effect = −0.05, p < 0.01,), while the mediating effect was 31.25% of the total effect. Our analysis testing the moderating effect showed that psychological flexibility significantly moderated the relationship between cyberloafing and state anxiety (interaction effect = −0.26, p < 0.01). And our analysis testing the moderated mediating effect showed that psychological flexibility played a moderating role in the mediating effect of state anxiety.ConclusionBased on the findings of this study, college students' cyberloafing negatively affects their sense of meaning of life. Therefore, appropriate measures should be taken to supervise and restrict college students' Internet use and provide them with corresponding guidance; certain psychological adjustment measures should also be taken when necessary to help college students with low psychological flexibility in reducing their state anxiety and improving their sense of meaning of life.