Slightly acidic electrolyzed water treatment enhances the quality attributes and the storability of postharvest litchis through regulating the metabolism of reactive oxygen species.

Effects of slightly acidic electrolyzed water (SAEW) on the storability, quality attributes, and reactive oxygen species (ROS) metabolism of litchis were investigated. Results showed that SAEW-treated litchis presented better quality attributes and storability than control litchis. On storage day 5, the commercially acceptable fruit rate of control litchis was 42%, while SAEW-treated litchis displayed 59% higher rate of commercially acceptable fruit, 21% lower pericarp browning index, and 13% lower weight loss percentage than control litchis. Additionally, compared to control litchis, SAEW-treated litchis demonstrated higher activities of SOD, CAT and APX, higher levels of GSH, AsA, DPPH radical scavenging ability, and reducing power, but lower O2 -· generation rate, lower levels of H2O2 and MDA. These findings indicated that SAEW treatment could elevate antioxidant capacity and ROS scavenging ability, reduce ROS production and accumulation, and lower membrane lipid peroxidation, thereby retaining the quality attributes and storability of litchis.

Predictive value of serum human epididymis protein 4 for heart failure in patients with chronic kidney disease.

AIM: To investigate the predictive value of human epididymis protein 4 (HE4) for heart failure in patients with chronic kidney disease (CKD). METHODS: This study retrospectively analyzed the data of 241 patients with CKD admitted to Zhangjiakou First Hospital from January 2019 to January 2021. The subjects were divided into a heart failure (HF) group (n=117) and a non-HF group (n=124) according to whether heart failure occurred. The baseline data and laboratory hematologic indicators (complete set of HE4, blood routine and biochemistry) were collected and analyzed by univariate analysis. Subsequently, the variables that were significant in the correlation analysis were included in a multi-factor logistic regression analysis. RESULTS: The HF group exhibited higher serum creatinine, HE4, hemoglobin, total cholesterol, triglycerides (TG), high-density lipoprotein (P<0.05), as well as higher B-type natriuretic peptide (BNP), creatine kinase, and creatine kinase-MB than the non-HF group, with significant differences (P<0.05). Spearman's rank correlation analysis revealed that age, HE4, calcium, TG, BNP and left ventricle ejection fraction were associated with the occurrence of heart failure (P<0.05). Multivariate analysis demonstrated that HE4 was a significant factor that could predict the development of heart failure in CKD patients (P<0.01), and the risk of heart failure was higher when HE4>27.2368 pmol/L. CONCLUSIONS: HE4 is an important factor for predicting the occurrence of heart failure in CKD patients. A higher HE4 level predicts greater possibility of heart failure.

The development of a rapid and highly sensitive monitoring system for radioxenon isotopes.

The rapid monitoring of radioactive gas is one of the most direct and sensitive methods used to characterize the leakage of nuclear installations, and its technical difficulty lies in achieving the goals of rapid and high sensitivity as much as possible. Several techniques, including adsorption at ultralow temperatures, impurity removal with hollow fiber membranes, and on-site measurements with low background, were used to develop a rapid and highly sensitive monitoring system for radioxenon isotope. This system could simultaneously separate xenon from air and measure radioxenon isotopes in a rapid and efficient way. The technical specifications of this system are as follows: the recovery of stable xenon is greater than 70%; and the MDCs of 133Xe and 135Xe are 4.3 Bq/m3 and 0.4 Bq/m3 within a 30 min cycle of sampling and testing, respectively. It is worth noting that the MDC of 133Xe here is only approximately 1/18000 to 1/800 of those obtained with other similar equipment, and the monitoring period of this system is one fortieth of that of noble gas equipment for OSI, for example, XESPM-III. As a result, the standard uncertainties are less than 16%. The system developed in this paper can be applied in leakage monitoring of nuclear facilities and can also provide instructive technical support for other tests, such as nuclear safety monitoring and evaluation.

Radon removal trap design and coefficient testing for the development of an effective radioxenon sampling, separation and measurement system.

To monitor low-level radioxenon isotopes activity concentrations in the bulk gases, a radioxenon sampling, separation and measurement system has been developed. The xenon enrichment factor of this system is more than 105 after the separation of impurities, including N2, O2, CO2and H2O, as well as radon and its progenies, such as 214Pb and 214Bi. Since radon and its progenies interfere with radioxenon measurement, they have to be removed before radioxenon counting. To separate radon from xenon, different dynamic adsorption coefficients of xenon and radon are used to design small radon removal trap to retain radon after eluting xenon, and the ratio between radon and xenon dynamic adsorption coefficient gives the adsorbent weight relationship between the xenon adsorption trap and its related radon removal trap. To test the effectiveness of radon removal, the relative measuring method is used by measuring γ-rays energies of radon progenies in canister filling with either the measuring sample prepared by the system or the original gas. The results show that the radon removal coefficient and the stable xenon recovery, which are two important parameters in the radioxenon system, are at the order of 10-6 and >70% respectively. These meet the specifications proposed by the Comprehensive Nuclear-Test-Ban Treaty Organization.

Development of a mobile radioxenon processing system for on-site inspections and the deployment in IFE14.

A mobile radioxenon gas processing system (XESPM-III) was developed for on-site inspections-targeting deployment in the Integrated Field Exercise in Jordan 2014 (IFE14)-in order to monitor radioxenon isotopes (131m,133,133m,135Xe) from the subsoil and atmosphere. XESPM-III is composed of primarily three units, the sampling unit, the purification unit and finally the quantification unit. The function of the sampling unit is to pre-enrich xenon by removal of impurities in the gas sample, while the purification unit further purifies, separates impurities and prepares a small-volume sample with relatively high concentration of xenon gas-both stable and radioactive xenon (if present). The quantification unit quantifies the stable xenon which provides information of the gas recovery (yield) of the gas sampling and purification process. In one cycle (7.5 h) XESPM-III can process either two 4 m3 volume samples or two pairs 2 m3 samples each; 24 h maximum throughput is thus twelve 2 m3 samples or six 4 m3 samples; final purified gas sample volume is approx. 7 cm3 (Xe + N2 used as carrier gas); gas recovery (yield) is >70%; radon removal coefficient is 10-6; cross contamination between subsequent samples is <1%; Its flexible design, that does not include a spectrometry system, allows it to be used with various spectrometric systems (HPGe, beta-gamma coincidence) for the final measurement of the radioactive xenon concentrations in the sample. During the field deployment of the XESPM-III in IFE14 it was able to measure 133Xe in the range of 0.18-0.54 Bq/m3 in spiked subsoil gas.

The determination of trace amounts of natural 133Xe in gas under high radon activity concentration levels.

Radioxenon monitoring has become one of the major concerns in both international monitoring systems and on-site inspection. The most important technical specifications for radioxenon system are the radon removal coefficient and the minimum detectable activity concentration. We have developed one kind of on-site radioxenon sampling, separation and measurement system, and have tested it under high radon activity concentration levels. The result shows the natural (133)Xe background activity concentration, the (133)Xe/(222)Rn ratio and the radon removal coefficient to be in the ranges 0.73-1.6 mBq/m(3), (1.5-3.5) × 10(-8) and (2.3-57) × 10(-8), respectively.

Atmospheric radioxenon isotope monitoring in Beijing after the Fukushima nuclear power plant accident.

A custom-made, on-site radioxenon sampling, separation and monitoring system was used to monitor atmospheric radioxenon concentrations in Beijing, released from the Fukushima Daiichi nuclear power plant after the earthquake of 11 March 2011. The results show that (133)Xe concentrations ranged from 393 to 26 mBq/m(3) from 12 to 27 April 2011, and those of (131 m)Xe were 84 and 40 mBq/m(3) on 13 and 15 April 2011, respectively. The highest dose rate caused by (133)Xe was 2 × 10(-5)mSv/yr, and the average (133)Xe/(131 m)Xe ratio was 3.8 ± 0.4.

[Synthesis of new N3S pseudo-peptide complexes and biodistribution in mice].

AIM: To explore the synthetic methods of polypeptides containing new heart of kidney imaging agents. METHODS AND RESULTS: Five new target chelators--2-N-(2'-s-triphenylmethylacetyl) amino-(N'-2"-N",N"-diethylethylamine) phenylpropamide (MPNE), 2-N-(2'-s-triphenylmethyl acetyl) amino-(N'-2"-N",N"-dimethylethylamine) phenylpropamide (MPNM), 2-N-(2's-triphenylmethylacetyl) amino-3-methyl-(N'-2"-N",N"-dimethylethylamine) butyramide (MVNM), 2-N-(2'-s-triphenyl methylacetyl) amino-3-methyl-(N'-2"-N",N"-diethylethylamine) butyramide (MVNE), 2-N-(2'-s-triphenylmethylacetyl) amino-(N'-acetylglycine) phenylpropamide (MPG2)--were synthesized through five steps with mercaptoacetic acid as primitive materials, all of which were identified on the basis of spectroscopic data, such as IR, 1HNMR, MS or elementary analysis. The protection of the mercapto group was improved and the relatively new reaction condition of active ester with amino acid is developed. All the chelators were labeled with Technetium-99m and their biological activities in mice given in ID values was tested to explore new heart imaging agents, where ID is the percentage injected dose per organ. The ID was determined by in vivo biodistribution study. Tc-99m complexes 0.1 mL was injected into the laterial tail vein of 3 anaesthetised rats. At 2, 5, 10, 30, 60 min post-injection, rats were sacrificed by decapitation, bled from the neck and dissected. Organs were removed at dissection. The radioactivities in various organs were determined in an automatic twin crystal gamma counter. CONCLUSION: The bio-distribution results in mice indicate that 99Tcm-MVNM have higher heart uptake (ID = 8.40%/g, 2 min post-injection) and quicker blood clearance (ID = 4.3%/g, 60 min post-injection); 99Tcm-MPNE and 99Tcm-MPNM also have fairly high heart uptake and quick blood clearance; 99Tcm-MPG2 has better kidney accumulation and higher activity ratios of kidney to blood (about 4).