Survival strategies of ammonia-oxidizing archaea (AOA) in a full-scale WWTP treating mixed landfill leachate containing copper ions and operating at low-intensity of aeration.

Recent studies indicate that ammonia-oxidizing archaea (AOA) may play an important role in nitrogen removal by wastewater treatment plants (WWTPs). However, our knowledge of the mechanisms employed by AOA for growth and survival in full-scale WWTPs is still limited. Here, metagenomic and metatranscriptomic analyses combined with a laboratory cultivation experiment revealed that three active AOAs (WS9, WS192, and WS208) belonging to family Nitrososphaeraceae were active in the deep oxidation ditch (DOD) of a full-scale WWTP treating landfill leachate, which is configured with three continuous aerobic-anoxic (OA) modules with low-intensity aeration (≤ 1.5 mg/L). AOA coexisted with AOB and complete ammonia oxidizers (Comammox), while the ammonia-oxidizing microbial (AOM) community was unexpectedly dominated by the novel AOA strain WS9. The low aeration, long retention time, and relatively high inputs of ammonium and copper might be responsible for the survival of AOA over AOB and Comammox, while the dominance of WS9, specifically may be enhanced by substrate preference and uniquely encoded retention strategies. The urease-negative WS9 is specifically adapted for ammonia acquisition as evidenced by the high expression of an ammonium transporter, whereas two metabolically versatile urease-positive AOA strains (WS192 and WS208) can likely supplement ammonia needs with urea. This study provides important information for the survival and application of the eutrophic Nitrososphaeraceae AOA and advances our understanding of archaea-dominated ammonia oxidation in a full-scale wastewater treatment system.

Xanthone derivatives from the fermentation products of an endophytic fungus Phomopsis sp.

Three new xanthones, 1-hydroxy-3-hydroxyethyl-5-methoxy-6-methoxycarbonylxanthone (1), 1,4-dihydroxy-3-hydroxyethyl-5-methoxy-6-methoxycarbonylxanthone (2), and 1-hydroxy-3-hydroxyethyl-4-methoxy-8-methoxycarbonylxanthone (3), together with five known xanthones (4-8) were isolated from the fermentation products of an endophytic fungus Phomopsis sp.. Their structures were elucidated by spectroscopic methods including extensive 1D- and 2D-NMR spectroscopic techniques. Compounds 1-3 and 7 were also tested for their cytotoxicity against five human tumor cell lines (NB4, A549, SHSY5Y, PC3, and MCF7) by the MTT method, with paclitaxel used as the positive control. Compound 1 showed cytotoxicity against A549 and PC3 cells with IC50 values of 3.2 and 2.5 µM, respectively, 2 showed potential cytotoxicity against NB4 cells, with an IC50 value of 3.6 µM, and 3 showed cytotoxicity against A549 cells with an IC50 value of 3.5 µM.

Five new prenylated chalcones from Desmodium renifolium.

Five unusual new prenylated chalcones, renifolins D-H (1-5), were isolated from whole Desmodium renifolium plants. All of their structures were determined by spectroscopic methods including 1D and 2D NMR. All of the isolates were evaluated for cytotoxicity using five tumor cell lines. Compounds 2 and 3 exhibited cytotoxicity against A549 cells, with IC50 values of 2.8 and 2.2 µM, respectively.

[Viable myocardium detecting by CARTO voltage mapping in swine model of acute myocardial infarction].

OBJECTIVE: To evaluate the accuracy and practicability of detecting viable myocardium by CARTO voltage mapping in swine model of acute myocardial infarction (MI). METHODS: MI was induced in 13 anesthetized swines via occluding the distal of left anterior descending coronary arteries by angioplasty balloon for 60-90 minutes. The viable myocardium detection by CARTO voltage mapping was made after reconstruction of the left ventricle using CARTO and the results were compared with TTC staining. The standard of CARTO voltage to detect viable myocardium was 0.5 - 1.5 mV while viable myocardium showed pink color by TTC staining. RESULTS: Eleven out of 13 swines survived the operation and 2 swines died of ventricular fibrillation at 45 and 65 minutes post ischemia. Left ventricle was divided into 16 segments and 176 segments from 11 swines were analyzed. Viable myocardium detected by CARTO voltage mapping was identical as identified by TTC staining (Kappa = 0.816, P < 0.001). Taken the TTC result as standard, the sensitivity, specificity and accuracy rate of CARTO voltage mapping are 71.8%, 96.5% and 90.9% respectively. CONCLUSION: CARTO voltage mapping could be used as a reliable tool to detect viable myocardium in this model.

[Response of net photosyntheitc rate to light and CO2 in Schisandra chinensis from different region and growing situation].

American CI-340 portable photosynthesis system was applied to compare the response of the net photosyntheitc rate to the light and the CO2 in Schisandra chinensis form different region and growing situation. The result showed the sample plant from Liaoning had higher light compensate point, higher light saturation point, higher maximum Pn value and higher apparent quantum yield than the sample from Jilin, so it can adapt to the changes of the sunlight in a day better. The weak plant from Jilin had lower light compenstate point, higher light saturation point and higher net photosynthetic rate, so it had stronger availability on light. The stronger one was more sensitive to the weak light. The Jilin sample had higher CE and lower CO2 compensate point compared to that from Liaoning, but when the density of CO2 rised to 240 micromol/mol, the Pn of Schisandra chinensis in Liaoning became much higher than that of Jilin. Under the natural CO2 density condition, the plant from Liaoning had higher photosynthesis ability.