[Effects of elevated CO2 concentration, warming, and winter wheat planting on soil enzyme activities.] / CO2æµ“åº¦å‡é«˜ã€å¢žæ¸©å’Œå†¬å°éº¦ç§æ¤å¯¹åœŸå£¤é ¶æ´»æ€§çš„å½±å“.

Understanding the responses of soil enzyme activities to elevated CO2 concentration and warming can provide a scientific basis for nutrient management of croplands under global climate change. We conducted a pot expe-riment with climate chamber to examine the effects of elevated CO2 concentration and warming and winter wheat growth on soil enzyme activities. There were four climate scenarios: control (CK, 400 µmol·mol-1 CO2 concentration+normal ambient temperature), and CO2 concentration elevation (ECO2, 800 µmol·mol-1 CO2 concentration+normal ambient temperature), elevated temperature (ET, 400 µmol·mol-1 + temperature increased 4 ℃), and elevated CO2 concentration and temperature (ECO2+T, 800 µmol·mol-1 CO2 concentration + temperature increased 4 ℃). We measured the activities of soil ß-glucosidase (ßG), ß-N-acetyl glucosidase (NAG), alkaline phosphate (ALP) and polyphenol oxidase (PPO) at four growth stages (JS, jointing stage; AS, anthesis stage; FS, filling stage and MS, maturity stage), with and without winter wheat planting. Without winter wheat planting, there was no significant difference in four kinds of soil enzyme activities between ECO2 and CK, while ET and ECO2+T treatments had significant negative effect on soil enzyme activities. With winter wheat planting, compared with CK, ECO2 and ECO2+T treatments did not affect the activities of those four soil enzyme; but the ET treatment had great impact on soil ALP and PPO activities. The activities of four kinds of soil enzyme were significantly diffe-rent between the ET and ECO2+T treatments. Compared with ET treatment, ECO2+T treatment increased soil ßG activity at the JS, decreased NAG activity at the JS, increased ALP activity at both AS and FS, decreased PPO activity in the JS and increased in the AS. The interaction of elevated CO2 concentration and warming had significant effect on soil NAG and ALP activities with and without winter wheat planting. The interaction of warming and expe-rimental stage had significant effect on four kinds of soil enzyme activities without winter wheat planting, but the interaction of warming and crop growth stage had significant effect on ALP and PPO activities with winter wheat planting. The interaction of elevated CO2 concentration, warming and experimental period had significant effect on soil ßG, ALP and PPO activities without winter wheat growth, while with winter wheat growth, it had significant impact on NAG, ALP and PPO activities. The winter wheat growth had significantly inhibitory effect on ßG, NAG and ALP activities in the two early growth periods (JS+AS), significant promoting effect in the later growth periods (FS+MS), and significantly inhibitory effect on PPO activity during whole growth period. Overall, elevated CO2 concentration did not affect soil enzyme activities, while the elevation of CO2 concentration and temperature on soil enzyme activities differed among the soil enzymes at different growth stages. In addition, the responses of four soil enzyme activities to the interaction of elevated CO2 concentration and warming varied with and without winter wheat planting.

[Analysis of Agranulocytosis Time and Its Influencing Factors in Patients with Hematological Malignancies Treated with rhIL-11 combined rhG-CSF].

OBJECTIVE: To explore the intervention effect of recombinant human interleukin-11 (rhIL-11) and recombinant human granulocyte-colony stimulating factor (rhG-CSF) on the duration and severity of agranulocytosis in patients with hematological malignancies after chemotherapy, and to analyze the influencing factors. METHODS: The data of hematological malignancy patients treated with rhIL-11 and rhG-CSF after chemotherapy in the hematology department of The First Hospital of Lanzhou University from July 2017 to July 2020 were collected retrospectively. The duration and differences of agranulocytosis in differeent groups were compared by univariate analysis, and the influencing factors of agranulocytosis duration were further analyzed by multiple regression analysis. RESULTS: The duration of agranulocytosis in 97 patients was 6.47±2.93 days. The results of univariate analysis showed that there were no statistical differences in the duration of agranulocytosis among patients with different sex, age, height, weight, body surface area, body mass index (BMI), dose of rhG-CSF, dose of rhIL-11, spontaneous bleeding after administration of rhG-CSF and rhIL-11, and the duration of agranulocytosis in patients with different red blood cell count (RBC), hemoglobin(HGB) level, platelet count (PLT) and absolute neutrophil count (ANC), before administration of rhG-CSF and rhIL-11. There were significant differences in agranulocytosis time among patients with different disease types, chemotherapy cycle, fever after rhG-CSF and rhIL-11 administration, and different white blood cell count (WBC) baseline level before rhG-CSF and rhIL-11 administration (P＜0.05). Compared with patients with acute lymphoblastic leukemia (ALL) and non-Hodgkin lymphoma (NHL), patients with acute myeloid leukemia (AML) had the longest duration of agranulocytosis, which was 7.07±3.05 d. Compared with patients with chemotherapy cycles of 4－6 and ≥7, patients with total chemotherapy cycle of 1－3 had the shortest duration of agranulocytosis, which was 5.25±2.48 d. Compared with patients without fever, patients with fever within 1 day after administration of cytokines and patients with fever within 2-5 days after administration of cytokines, the duration of agranulocytosis was the longest in patients with fever 6 days after administration of cytokines, which was 8.85±2.85 d. Compared with patients with WBC baseline <1.0×109/L, (1.0－1.9)×109/L and (2.0－3.9)×109/L, patients with WBC baseline ≥4.0×109/L had the shortest duration of agranulocytosis, which was 4.50±2.56 d. Multiple linear regression analysis showed that chemotherapy cycle, different fever after administration of rhG-CSF and rhIL-11, diagnosis of ALL and NHL, and WBC baseline level before administration of rhG-CSF and rhIL-11 were the influencing factors of the duration of agranulocytosis (P＜0.001). CONCLUSION: The risk of prolonged agranulocytosis is higher in patients diagnosed with AML, with more chemotherapy cycles, lower WBC baseline before cytokines administration and fever later after cytokines administration, which should be paid more attention to.

Combining antioxidant astaxantin and cholinesterase inhibitor huperzine A boosts neuroprotection.

Oxidative stress is a pathophysiological condition resulting in neurotoxicity, which is possibly associated with neurodegenerative disorders. In this study, the antioxidative effects of the antioxidant astaxanthin (AXT) in combination with huperzine A (HupA), which is used as a cholinesterase inhibitor for the treatment of Alzheimer's disease, were investigated. PC12 cells were treated with either tert­butyl hydroperoxide (TBHP), or with the toxic version of ß­amyloid, Aß25­35, to induce oxidative stress and neurotoxicity. Cell viability, morphology, lactate dehydrogenase (LDH) release, intracellular accumulation of reactive oxygen species (ROS), superoxide dismutase (SOD) activity and malondialdehyde (MDA) content were determined, while neuroprotection was also monitored using an MTT assay. It was found that combining AXT with HupA significantly increased the viability of PC12 cells, prevented membrane damage (as measured by LDH release), attenuated intracellular ROS formation, increased SOD activity and decreased the level of MDA after TBHP exposure when compared to these drugs administered alone. Pretreatment with HupA and AXT decreased toxic damage produced by Aß25­35. These data indicated that combining an antioxidant with a cholinesterase inhibitor increases the degree of neuroprotection; with future investigation this could be a potential therapy used to decrease neurotoxicity in the brain.