Physicochemical and Rheological Properties of Degraded Konjac Gum by Abalone (Haliotis discus hannai) Viscera Enzyme.

In the present study, a new degraded konjac glucomannan (DKGM) was prepared using a crude enzyme from abalone (Haliotis discus hannai) viscera, and its physicochemical properties were investigated. After enzymatic hydrolysis, the viscosity of KGM obviously decreased from 15,500 mPa·s to 398 mPa·s. The rheological properties analysis of KGM and DKGMs revealed that they were pseudoplastic fluids, and pseudoplasticity, viscoelasticity, melting temperature, and gelling temperature significantly decreased after enzymatic hydrolysis, especially for KGM-180 and KGM-240. In addition, the molecular weight of KGM decreased from 1.80 × 106 Da, to 0.45 × 106 Da and the polydispersity index increased from 1.17 to 1.83 after 240 min of degradation time. Compared with natural KGM, the smaller particle size distribution of DKGM further suggests enzyme hydrolysis reduces the aggregation of molecular chains with low molecular weight. FT-IR and FESEM analyses showed that the fragmented KMG chain did not affect the structural characteristics of molecular monomers; however, the dense three-dimensional network microstructure formed by intermolecular interaction changed to fragment microstructure after enzyme hydrolysis. These results revealed that the viscosity and rheological properties of KGM could be controlled and effectively changed using crude enzymes from abalone viscera. This work provides theoretical guidance for the promising application of DKGM in the food industry.

Characterization of Fatigue Crack Growth Based on Acoustic Emission Multi-Parameter Analysis.

In engineering structures that are subject to cyclic loading, monitoring and assessing fatigue crack growth (FCG) plays a crucial role in ensuring reliability. In this study, the acoustic emission (AE) technique was used to monitor the FCG behavior of 2.25Cr1Mo0.25V steel in real-time. Specifically, an AE multi-parameter analysis was conducted to qualitatively assess the crack growth condition and quantitatively correlate the crack growth rate with AE. Various AE parameters were extracted from AE signals, and the performances of different AE parameters were analyzed and discussed. The results demonstrated that four stages of FCG, which correspond to macrocrack initiation, stable crack growth with low crack growth rate, stable crack growth with high crack growth rate, and unstable crack growth, are distinctly identified by several AE time domain parameters. The sudden and continuous occurrence of many AE signals with high count (>100) and high energy (>40 mV·ms) can provide early and effective warning signs for accelerated crack growth before final failure occurs. Moreover, linear correlations between crack growth rate and different AE parameters are established for quantifying crack growth. Based on the AE multi-parameter analysis, it was found that the count, energy, and kurtosis are superior AE parameters for both qualitatively and quantitatively characterizing the FCG in 2.25Cr1Mo0.25V steel. Results from this research provide an AE strategy based on multi-parameter analysis for effective monitoring and assessment of FCG in engineering materials.

MicroRNA-760 acts as a tumor suppressor in gastric cancer development via inhibiting G-protein-coupled receptor kinase interacting protein-1 transcription.

BACKGROUND: Gastric cancer (GC) has become a serious threat to people's health. Accumulative evidence reveals that dysregulation of numerous microRNAs (miRNAs) has been found during malignant formation. So far, the role of microRNA-760 (miR-760) in the development of GC is largely unknown. AIM: To measure the expression level of miR-760 in GC and investigate its role in gastric tumorigenesis. METHODS: Real-time quantitative polymerase chain reaction and Western blot analysis were used to measure the expression of miR-760 and G-protein-coupled receptor kinase interacting protein-1 (GIT1). Cell growth was detected by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) and cell colony formation assays. Apoptosis was assessed by flow cytometric analysis. The relationship between miR-760 and GIT1 was verified by luciferase reporter assay. RESULTS: The results showed that the expression of miR-760 was decreased in GC and associated with poor clinical outcomes in GC patients. Furthermore, miR-760 restrained cell proliferation and cell colony formation and induced apoptosis in GC cells. In addition, miR-760 directly targeted GIT1 and negatively regulated its expression in GC. GIT1 was upregulated in GC and predicted a worse prognosis in GC patients. We also found that upregulation of GIT1 weakened the inhibitory effect of miR-760 in GC. CONCLUSION: In conclusion, miR-760 targets GIT1 to inhibit cell growth and promote apoptosis in GC cells. Our data demonstrate that miR-760 may be a potential target for the treatment of GC.

A Multicenter, Randomized, Controlled Trial of Electroacupuncture for Perimenopause Women with Mild-Moderate Depression.

OBJECTIVE: Up to 62% of perimenopausal women have depression symptoms. However, there is no efficacy treatment. The aim of this study is to compare the clinical efficacy and safety of EA therapy and escitalopram on perimenopause women with mild-moderate depressive symptom. METHOD: A multicenter, randomized, positive-controlled clinical trial was conducted at 6 hospitals in China. 242 perimenopause women with mild-moderate depressive symptom were recruited and randomly assigned to receive 36 sessions of EA treatment or escitalopram treatment. The primary outcome measure was the 17-item Hamilton Depression Rating Scale (HAMD-17). The secondary outcome measures include menopause-specific quality of life (MENQOL) and serum sexual hormones which include estrogen, follicle-stimulating hormone, and luteinizing hormone. RESULTS: 221 (91.3%) completed the study, including 116 in the EA group and 105 in the escitalopram group. The baseline levels of demographic and outcome measurements were similar in the two groups. In the intervention period, there was no difference between two groups. However, in the follow-up, both HAMD-17 and MENQOL were significantly decreased, and at week 24 the mean differences were -2.23 and -8.97, respectively. There were no significant differences in the change of serum sexual hormones between the two groups. No serious adverse events occurred. CONCLUSION: EA treatment is effective and safe in relieving depression symptom and improving the quality of life in the perimenopausal depression. Further research is needed to understand long-term efficacy and explore the mechanism of this intervention. This study is registered with ClinicalTrials.gov NCT02423694.