Analyzing the effect of storage conditions on anammox recovery performance from the perspectives of time, temperature and biomass form.

In this study, the effects of different storage conditions, such as temperature, storage time and biomass form, on the properties of anaerobic ammonia oxidation (anammox) were investigated along with the identification of the process mechanism. The results showed that the influence of storage time on anammox properties was stronger than that of storage temperature and biomass form. Also, the anammox recovery activity at 15 °C was better than that at 4 °C, and the anammox recovery activity of immobilized filler was better than that of anammox granular sludge (AnGS). Although cryogenic storage severely damaged anammox activity, lower loss of extracellular polymeric substances maintained the AnGS structure. The maximum recovery of specific anammox activity at 15 °C for the immobilized filler was observed to be 109%. In addition, intermittent substrate supplementation weakened the adverse effect of long-term storage on anammox activity, and was conducive to maintaining stable flora composition and promoting regeneration of anammox bacteria (AnAOB). High-throughput sequencing analysis showed that starvation resulted in increased community diversity, and the functional bacteria Candidatus Brocadia was observed to be more tolerant to starvation than Candidatus Kuenenia. Finally, principal component analysis was used to explain the complex relationship between process performance and preservation conditions. Based on the results of this work, it is recommended to preserve AnAOB in the form of immobilized filler at 15 °C and supplement substrate intermittently during long term storage. This study provides an economical and robust strategy for the short-term and long-term preservation of AnAOB.

Biomarker characteristics of Montney source rock, British Columbia, Canada.

Montney Formation (MF) source rock located in northeastern British Columbia (BC), Canada, was analyzed to determine its depositional conditions and organic matter source input other than to determine their level of thermal maturity. The high total sulfur (TS) (2.23-20.86 wt.%) and good to very good total organic carbon (TOC) content (0.3-5.87 wt.%) in the analyzed samples give good evidence that the deposition of MF source rock was in a marine environment under reducing conditions. A mixed marine-terrestrial derived organic matter (OM) for the Montney source rock that was deposited in a marine dysoxic environment is deduced from the composition and distribution of different biomarker traces. Thus, the previous result is supported by the high short-chain n-alkanes ratio, accompanied by carbon preference index (CPI) around unity, high concentration of tricyclic terpanes, high C24 tricyclic/C24 tetracyclic, hopane/sterane ratios ranging from low to moderate, as well as the relationship between regular sterane compositions. During deposition of the MF source rock, it can be noticed that more land organic materials this was deduced according to the high waxiness index. From maturity ratios of Ts/(Ts + Tm), C32 22S/(22S + 22R) homohopane, moretane/hopane and 20S/(20S + 20R) and ßß/(ßß + αα) C29 it can give a conclusion that the source rock is mature to postmature of hydrocarbon generation.

Effects of graft preservation conditions on coronary endothelium and cardiac functional recovery in a rat model of donation after circulatory death.

BACKGROUND: Use of cardiac grafts obtained with donation after circulatory death (DCD) could significantly improve donor heart availability. As DCD hearts undergo potentially deleterious warm ischemia and reperfusion, clinical protocols require optimization to ensure graft quality. Thus, we investigated effects of alternative preservation conditions on endothelial and/or vascular and contractile function in comparison with the current clinical standard. METHODS: Using a rat DCD model, we compared currently used graft preservation conditions, St. Thomas n°2 (St. T) at 4°C, with potentially more suitable conditions for DCD hearts, adenosine-lidocaine preservation solution (A-L) at 4°C or 22°C. Following general anesthesia and diaphragm transection, hearts underwent either 0 or 18 min of in-situ warm ischemia, were explanted, flushed and stored for 15 min with either St. T at 4°C or A-L at 4°C or 22°C, and then reperfused under normothermic, aerobic conditions. Endothelial integrity and contractile function were determined. RESULTS: Compared to 4°C preservation, 22°C A-L significantly increased endothelial nitric oxide synthase (eNOS) dimerization and reduced oxidative tissue damage (p < 0.05 for all). Furthermore, A-L at 22°C better preserved the endothelial glycocalyx and coronary flow compared with St. T, tended to reduce tissue calcium overload, and stimulated pro-survival signaling. No significant differences were observed in cardiac function among ischemic groups. CONCLUSIONS: Twenty-two-degree Celsius A-L solution better preserves the coronary endothelium compared to 4°C St. T, which likely results from greater eNOS dimerization, reduced oxidative stress, and activation of the reperfusion injury salvage kinase (RISK) pathway. Improving heart preservation conditions immediately following warm ischemia constitutes a promising approach for the optimization of clinical protocols in DCD heart transplantation.

Observation of Whether to Mix Evenly the Serum Samples Preserved at-20℃ for Clinical Routine Biochemical Test Results / 现代检验医学杂志

Objective To explore the change of conventional biochemical test results of serum specimens saved-20℃ and blending of its effects.Methods The fresh serum of 24 patients were conducted routine biochemical tests,respectively in four groups of numbers in the same capacity of 1 ml of the sample tube,a set of 25℃ kept 24 hours a day,a group of 4 ℃ refrigerated for 24 hours,24 hours at-20℃ save the two groups (a group was not incorporated,a set of blended),and the four groups of serum samples in biochemical results comparing with the initial results.Results 25℃ at room temperature preservation after 24 hours,ALT,AST,TBIL and DBIL biochemical indicators of four average were below the initial results (t=2.130,2.308,2.130 and 2.308,P=0.042,0.029,0.042 and 0.003),there were no statistically significant difference between the rest of the biochemical index results comparison (P＞ 0.05).4℃ refrigerator after 24 hours,TBIL,DBIL levels below the initial level (t=2.103 and 2.089,P=0.045 and 0.046),and the rest of the biochemical indicators to compare differences had no statistical significance (P＞0.05).-20℃ refrigerated in the two groups of samples,not each sample of serum biochemical results compared with the initial results,were kept statistically significant difference (t=-4.218～11.710,all P＜0.05),while serum samples of 15 items and biochemical indexes of blending the results compared with the initial results,the average level of had no statistical significance (P＞0.05).Conclusion Serum samples of the chemical composition of the homogeneity in the 4 ℃ refrigerator will not change,but will not be able to timely detection of serum samples in the preservation,and minus-20 ℃ refrigerator on the serum samples of a significant difference was found in the lower concentration of chemical components,compete on low,and tests conducted before fully blending can ensure the precision of its biochemical test results.

Influence of different preservation conditions and times on the measurement of blood biochemical indicators in Beagle dogs / 中国比较医学杂志

Objective Beagle dogs are commonly used animal for drug safety evaluation .As the necessary parameters , blood biochemical indicators are detected in acute or chronic toxicity tests .This study aims at assessing the influence of different preservation conditions and different preservation time on blood biochemical indicators to ensure the reliability of test results of long-term toxicity assessment .Methods Six Beagle dogs (3 males and 3 females) were used in this study .After collection and preparation of serum samples , biochemical indicators were detected after preservation in refrigerator at 2-8℃for 1, 2, 5, 8, and 12 hours;after preservation in ice transportation boxes at 2-10℃for 2, 5, and 8 hours;and after preservation in refrigerator at -20℃ for 1, 3, and 5 days.The biochemical indicators included alanine aminotransferase ( ALT ) , aspartate aminotransferase ( AST ) and alkaline phosphatase ( ALP ) , total protein ( TP ) , albumin (propagated), urea, creatinine (CREA), glucose (GLU), total cholesterol (TCHO), total bilirubin (TBIL), creatine kinase ( CK ) , gamma pancreatic acyl transferase ( GGT ) , calcium ( CA ) , lactate dehydrogenase ( LDH ) , phosphorus ( P) , high-density lipoprotein cholesterol ( HDL-C) , low density lipoprotein cholesterol ( LDL-C) , triglyceride ( TG) , sodium ( Na+) , potassium ( K+) and chloride ( Cl -) .Results Compared with the results of samples preserved for 1 hour, the LDL-C result of that preserved in refrigerator at -20℃for 5 days was significantly increased (P0.05 ) , and the coefficient of variation of LDH was 41%.Conclusions According to the test results of blood biochemical indicators in the Beagle dogs detected after different preservation conditions and different preservation time in this study , detection test should be done within 1 hour, if not, detection should be done within 12 hours for the samples preserved at 2~8℃, or within 3 days for the sample preserved at -20℃.For transportation of serum samples , the serum samples should be placed in the ice box at 2~10℃, and detection test should be done within 8 hours .