RESUMEN
BACKGROUND: Previous studies have shown that the vitrification of metaphase II (MII) oocytes significantly represses their developmental potential. Abnormally increased oxidative stress is the probable factor; however, the underlying mechanism remains unclear. The walnut-derived peptide TW-7 was initially isolated and purified from walnut protein hydrolysate. Accumulating evidences implied that TW-7 was a powerful antioxidant, while its prospective application in oocyte cryopreservation has not been reported. RESULT: Here, we found that parthenogenetic activation (PA) zygotes derived from vitrified MII oocytes showed elevated ROS level and delayed progression of pronucleus formation. Addition of 25 µmol/L TW-7 in warming, recovery, PA, and embryo culture medium could alleviate oxidative stress in PA zygotes from vitrified mouse MII oocytes, furtherly increase proteins related to histone lactylation such as LDHA, LDHB, and EP300 and finally improve histone lactylation in PA zygotes. The elevated histone lactylation facilitated the expression of minor zygotic genome activation (ZGA) genes and preimplantation embryo development. CONCLUSIONS: Our findings revealed the mechanism of oxidative stress inducing repressed development of PA embryos from vitrified mouse MII oocytes and found a potent and easy-obtained short peptide that could significantly rescue the decreased developmental potential of vitrified oocytes, which would potentially contribute to reproductive medicine, animal protection, and breeding.
RESUMEN
Sensor technology plays a pivotal role in various aspects of the petroleum industry. The conventional quartz crystal microbalance (QCM) liquid-phase detection method fails to discern the viscosity and density of solutions separately, rendering it incapable of characterizing the properties of unknown liquid solutions. This presents a formidable challenge to the application of QCM in the petroleum industry. In this study, we aim to assess the feasibility of exclusively utilizing a single QCM sensor for liquid viscosity measurements. Validation experiments were conducted, emphasizing the influence of temperature and solution concentration on the viscosity measurement results. The results indicate that the QCM liquid viscosity response model can achieve viscosity measurements in the temperature range of 20 to 60 °C and concentration range of 10%-95% glycerol solution using a single QCM, with a maximum error of 7.32%. Simultaneously, with the objective of enhancing the model's measurement precision, as an initial investigation, we employed a backpropagation neural network combined with genetic algorithm (to optimize the measurement data. The results demonstrate a substantial improvement in the measurement accuracy of the QCM sensor, with a root mean square error of 3.89 and an absolute error of 3.07% in predicting viscosity values. The purpose of this research was to extend neural networks into the evaluation system of QCM sensors for assessing the viscosity properties of liquid in the oil industry, providing insights into the application of QCM sensors in the petroleum industry for viscosity measurement and improving measurement accuracy.
RESUMEN
This study fabricated nanocellulose lightweight porous material (TOCNF-G-LPM-TA) as absorbent fresh-keeping pad for meat products, using TEMPO-oxidized cellulose nanofibril (TOCNF) and gelatin as structural skeleton and tannic acid (TA) as antibacterial component of TOCNF lightweight porous material (TOCNF-G-LPM). The adsorption kinetics, capacity and mechanism of TOCNF-G-LPM in different initial concentrations of TA solutions were investigated, the antioxidant and antibacterial properties of TOCNF-G-LPM-TA and its fresh-keeping effect on refrigerated pork at 4 â were studied. Due to strong hydrogen bonding and porous structure, TOCNF-G-LPM exhibited excellent TA adsorption ability (230 mg/g) conforming with pseudo-second-order kinetic and Langmuir isotherm models. TA endowed TOCNF-G-LPM with good antioxidant and antibacterial activities. According to changes in appearance, pH and TVB-N values of pork during storage at 4 â, TOCNF-G-LPM-TA effectively extended the shelf life of refrigerated pork. This work provides a facile method for preparing nanocellulose based absorbent fresh-keeping pads.
