Environmental losses and driving forces of nitrogen flow in two agricultural towns of Hebei province during 1997-2017

Excessive nitrogen (N) losses from food production and consumption have resulted in noticeable environmental impacts, e.g., air pollution and climate change, saturation of soil N, and water eutrophication. In the present study, a rural-scale N flow model was constructed in Quzhou county, Hebei province to investigate the characteristics of the N flux, N use efficiency (NUE), and N loss and their driving factors in the food production and consumption system during 1997-2017. Our results show that the N fluxes of the crop-production subsystem (CPS), the livestock-breeding subsystem (LBS), and the household-consumption subsystem (HCS) all followed an upward trend. During 1997-2017, the N losses from the system were high (51.38%), and the CPS was a major source. When the N fertilizer application level was optimal (403-475 kg N ha^-1), the NUE in the CPS (NUEc) decreased sharply, resulting in a higher N cost than that observed at larger scales. For the LBS, the NUE of animal feed (NUEa) was high (46.37%); however, the waste utilization rate of the HCS was below 30%. The chemical fertilizer application level, feed input, animal-food demand, and livestock manure application level were closely related to the environmental N losses. Due to the lack of reasonable N treatment and utilization methods, the increasing N losses are expected to have a large future impact on environmental issues such as haze, soil acidification, and frequent algal blooms. Therefore, adjusting N management in the processes of food production and consumption is of great significance to the improvement of global NUE and reduction of environmental pollution.

Response of the nitrogen load and its driving forces in estuarine water to dam construction in Taihu Lake, China

To regulate the water level and minimize the occurrence of water eutrophication in shallow lakes, dams and gates are often constructed in rivers. However, this practice may result in a deterioration of water quality in some estuaries. In the present study, using the correction of Nemerow pollution index (CNPI) and a redundancy analysis (RDA), water samples from different dammed rivers around Taihu Lake were compared to assess the pollution risk and identify the factors responsible for water eutrophication. The average total nitrogen (TN), total phosphorus (TP), total organic carbon (TOC) concentrations, and chemical oxygen demand (CODMn) were 2.45 ± 2.28, 0.08 ± 0.06, 43.01 ± 18.75, and 10.78 ± 4.86 mg L-1, respectively. The CNPI values indicated that approximately 76.47% of the estuarine water was moderately polluted (1 < CNPI < 7.28). A positive correlation was observed between dam construction and nutrient concentrations (e.g., rTN = 0.38, p < 0.05; rTP = 0.89, p < 0.01). Under the effects of dam construction, land use change, estuary shape, and meteorological conditions, there was a clear spatial variation of the TN concentrations. Dams that were closed all year round accelerated the TN accumulation in the water around them. The pollution risk in a trumpet-shaped estuary was higher than that in other regions (t = 2.92, p = 0.02). Endogenous release of pollutants was an important factor that may have a priming effect on algal blooms and should be given more attention. In Wuli Lake, exogenous pollution was the dominant pollutant source. A total of 74.49% of the nitrogen losses with the runoff into the estuarine water in 2018 were derived from urban domestic sewage and constructed land, with the load being 4.40 times higher than in 2000. The RDA results revealed that dam construction was the main factor (43.70%) affecting water quality, while meteorological conditions, land use types, estuary shape, and other factors contributed 56.30%. Scientific regulation and control of dam operation is important to protect the water environment of Taihu Lake.

A three-gene signature and clinical outcome in pediatric acute myeloid leukemia

BACKGROUND

Although the 5-year survival rates in pediatric acute myeloid leukemia (AML) have improved over the last decades, there is a high relapse rate for Pediatric AML patients.

METHODS

In the present study, we mainly combine PCA with the LASSO technique to identify prognostic markers for Pediatric AML patients coming from the NCI TARGET database.

RESULTS

Three key genes (EEF1A1, RPLP2, RPL19) associated with poor prognosis of pediatric AML has been screened by both PCA and LASSO Cox regression analysis. Simultaneously, we developed a risk score model to predict the prognosis of pediatric AML, according to risk scores, the patients were divided into high- and low-risk groups based on the median risk score. Kaplan-Meier survival analysis indicated that Pediatric AML patients with the high-risk group have a poorer survival rate than those with a low-risk group (p < 0.000). The receiver operating characteristic (ROC) analysis showed that the risk model has a good performance (AUC:0.669). Moreover, the clinicopathologic correlation showed that the expression levels of three genes were related to the central nervous system (CNS) disease and chloroma. GSEA identified that those pathways including oxidative phosphorylation, apoptosis and TGFB signaling pathway were differentially enriched.

CONCLUSION

Taken together, those studies suggested that a gene panel that consists of three genes (EEF1A1, RPLP2, RPL19) may act as a potential prognostic marker.

C:N ratio is not a reliable predictor of N2O production in acidic soils after a 30-day artificial manipulation

To test the effect of C:N ratio on soil N₂O production, N₂O production rates and pathways associated with nitrification (AOA-amoA, AOB-amoA, fungal ITS rDNA, bacterial 16S rRNA), and denitrification-related (nirK, nirS, nosZ) genes were investigated in subtropical forest (SF) and cropland (SC) soil in China in a 30-day C:N ratio manipulation. In addition, 24-hour C:N ratio manipulation, including the addition of acetic acid, were conducted to verify the results observed in the 30-day experiment. After 30 days of manipulation, the N₂O production rates (N₂O_t) increased from 2.46 in CN23 treatment to 4.71 μg N kg^-1 day^-1 in CN 10 treatment in SF, while it decreased from 4.17 in CN23 treatment to 3.83 μg N kg^-1 day^-1 in CN10 treatment in SC. The results in 24-hour experiment were consistent with those in 30-day experiment, and the addition of acetic acid increased N₂O_t in SC, but not in SF. Soil C:N ratios and inorganic N (NH₄⁺ + NO₃^-) concentrations influenced the contribution of denitrification to N₂O production and the N₂O production rate via denitrification. Soil AOA played a dominant role in autotrophic nitrification-derived N₂O production, resulting in a high contribution of autotrophic nitrification under low pH. Therefore, pH instead of C:N ratio, is a key parameter for evaluating autotrophic nitrification-derived N₂O via AOA and AOB. Soil C:N ratio was significantly and positively correlated with the contribution of heterotrophic nitrification to N₂O production, while there was no significant correlation with the N₂O production rate via heterotrophic nitrification. This is mainly because the responsible heterotrophs (i.e., fungi and bacteria) were negatively and positively correlated with C:N ratio in SF and SC, respectively. Therefore, C:N ratio is not a strong predictor of soil N₂O production, the initial C or N content and composition of functional genes could provide key information in acidic soils after a 30-day artificial C:N ratio manipulation.

PARE0026 WHICH PATIENT-REPORTED OUTCOMES DO RHEUMATOLOGY PATIENTS FIND IMPORTANT TO TRACK DIGITALLY? A REAL-WORLD LONGITUDINAL STUDY IN ARTHRITISPOWER

Background:

Development of a standardized approach to assess key elements of disease activity in rheumatology clinical trials has been the goal of Outcome Measures in Rheumatology Clinical Trials (OMERACT), American College of Rheumatology (ACR), and European League Against Rheumatism (EULAR).1,2,3The core sets of measures developed include assessments and composite indices incorporating use of patient-reported outcomes (PROs) and clinical measures and clinicians’ assessments to quantify disease activity over time.2PROs are important indicators of disease activity and variability, and they are increasingly used to evaluate treatment effectiveness. Little is known about PROs that patients with rheumatic conditions find most important to convey their experience with their condition and its treatment.

Objectives:

To examine PROs selected by patients with rheumatic conditions in the ArthritisPower registry to identify symptoms they found most important to track digitally.

Methods:

Adult US patients within the ArthritisPower registry with rheumatoid arthritis (RA), psoriatic arthritis (PsA), ankylosing spondylitis (AS), systemic lupus erythematosus (SLE), osteoporosis (OP), osteoarthritis (OA), and fibromyalgia syndrome (FMS) were invited via email to participate in this study. Enrolled participants (pts) were prompted to select ≤10 PRO symptom measures they felt were important to track for their condition at baseline via the ArthritisPower app. At 3 subsequent time points (Month [m] 1, m2, m3), pts were given the option to continue tracking their previously selected PRO measures or to add, remove and/or select different measures. At m3, pts completed an exit survey to prioritize ≤5 measures from all measures selected during study participation and to specify other symptoms not available that they would have wanted to track. Measures were rank-ordered based on number of pts rating the item as their 1st, 2nd, 3rd, 4th or 5th choice and weighted by multiplying the rank number by its inverse for a single, weighted summary score for each measure. Values were summed across all pts to produce a summary score for each measure.

Results:

Among pts who completed initial selection of PRO assessments at baseline (N=253), 184 pts confirmed or changed PRO selections across m1-3. Mean (SD) age of pts was 55.7 (9.2) yrs, 89.3% female, 91.3% White, mean disease duration of 11.6 (10.6) yrs. The majority (64.8%) self-reported OA, followed by RA (48.6%), FMS (40.3%), PsA (26.1%), OP (21.0%), AS (15.8%) and SLE (5.9%), not mutually exclusive, and were similar to the overall ArthritisPower population. The average number of instruments (SD) selected for baseline completion was 7.0 (2.5), 7.1 (2.4) at m1, 7.2 (2.4) at m2, and 7.0 (2.5) at m3. The top 5 PROs ranked by pts overall as most important (weighted summary score) for tracking were Fatigue (71), Physical Function (58), Pain Intensity (50), Pain Interference (49), Duration of Morning Joint Stiffness (41) (Figure 1). Fatigue, Physical Function, and Pain were consistently in the top 5 across diseases while Depression was more frequent among pts with OA, AS and FMS. Pts’ PRO selections showed stability over time except for the RA Flare measure which decreased from 70.5% of RA pts at baseline to 13.6% at m3.

Conclusion:

The symptoms prioritized by pts included fatigue, physical function, pain, and joint stiffness. Pts‘ choices were consistent over time. These findings provide insights into symptoms rheumatology patients find most important and will be useful to inform design of future patient-centric clinical trials and real-world evidence generation.

References:

[1]Boers M, et al. J Rheumatol Suppl. 1994;41:86–89.

[2]Felson DT, et al. Arthritis Rheum. 1993;36:729–740.

[3]Tugwell P, et al. J Rheumatol. 1993;20:555–556.

Disclosure of Interests:

W. Benjamin Nowell: None declared, Carol L. Kannowski Shareholder of: Eli Lilly and Company, Employee of: Eli Lilly and Company, Kelly Gavigan: None declared, Zhihong Cai Shareholder of: Eli Lilly and Company, Employee of: Eli Lilly and Company, Anabela Cardoso Shareholder of: Eli Lilly and Company, Employee of: Eli Lilly and Company, Theresa Hunter Shareholder of: Eli Lilly and Company, Employee of: Eli Lilly and Company, Shilpa Venkatachalam: None declared, Julie Birt Shareholder of: Eli Lilly and Company, Employee of: Eli Lilly and Company, Jennifer Workman Shareholder of: Eli Lilly and Company, Employee of: Eli Lilly and Company, Jeffrey Curtis Grant/research support from: AbbVie, Amgen, Bristol-Myers Squibb, Corrona, Janssen, Lilly, Myriad, Pfizer, Regeneron, Roche, UCB, Consultant of: AbbVie, Amgen, Bristol-Myers Squibb, Corrona, Janssen, Lilly, Myriad, Pfizer, Regeneron, Roche, UCB

Spatio-temporal dynamics of nitrogen use efficiencies in the Chinese food system, 1990-2017

Understanding the influence factors of nitrogen (N) use efficiencies (NUEs) in different stages of the food system at the provincial scale is critical to achieving cleaner food production while ensuring food security. Nevertheless, they are not well understood. Here we comprehensively analyzed NUE and its influence factors at different stages of the provincial food system. The results showed that per unit agricultural land N input increased by 5-92% in 27 provinces, during 1990-2010, resulting in a low NUE for the crop system when N input per unit agricultural land exceeded about 400 kg N ha^-1. This situation has brought some positive changes, as N input decreased by 3-271 kg N ha^-1 in 77% of the provinces in 2017, relative to that of 2010, but 10 provinces were still over 450 kg N ha^-1 in 2017. Animal food production is expected to continue to expand because 35% and 68% of provinces' urban and rural households, respectively, were still below the recommended minimum animal food N consumption recommendation in 2017, posing great challenges for reducing environmental N pollution. An exciting result is that the NUE of the animal system can be improved by increasing the share of animal food contributed by poultry, eggs, milk and fish, to align with the diets recommended by the Chinese Nutrition Society. NUEs of the provincial food systems excluding Inner Mongolia, Xinjiang, Qinghai and Tibet, would increase by 13% if the net imported food N increased by 1 kg capita^-1. Nevertheless, virtual NUE-including N input for imported food in the calculation of NUE-should be considered for accurate comparison of the NUEs of the provincial food systems, especially in highly urbanized areas, while N input for non-food animals should be excluded for accurate evaluation of the NUE in pastoral areas, considering their special production systems and feeding structures.

Dynamics of nitrite in acidic soil during extraction with potassium chloride studied using 15 N tracing

RATIONALE

Nitrite is well known to be unstable, including during soil extraction with KCl (especially in acidic soils), but the source and fate of NO₂ ^- in the short duration of the extraction process remain unclear.

METHODS

A series of ¹⁵ N-tracing studies explored NO₂ ^- transformations during KCl extraction in acidic and alkaline soils. Tests considering multiple factors assessed the interactions of such factors as soil sterilization, extraction time, and pH adjustment. After addition of ¹⁵ NO₂ ^- , ¹⁵ NH₄ ⁺ , and ¹⁵ NO₃ ^- tracers, the concentrations and isotopic compositions of N₂ O, N₂ , NH₄ ⁺ , NO₃ ^- , NO₂ ^- , and dissolved organic nitrogen (DON) were measured to investigate the production and consumption of NO₂ ^- .

RESULTS

Nitrite was stable in alkaline soils during KCl extraction. In contrast, changes did occur in acidic soils during KCl extraction: NO₂ ^- declined rapidly in the first 10 min of extraction although the subsequent rate of decrease lessened as the extraction time progressed. Significant dilution of ¹⁵ NO₂ ^- suggested high rates of NO₂ ^- production and even higher rates of consumption. The soil's organic N was the only source of NO₂ ^- and also its main destination. Soil sterilization showed that NO₂ ^- processes during extraction were chemical, not microbial. The pH adjustment of acidic soil stabilized its NO₂ ^- .

CONCLUSIONS

Overall, the pH adjustment of KCl solution appears favorable for investigating NO₂ ^- dynamics. For example, this work recommends an extraction solution comprising a 4:1 mixture of 2.5 M KCl solution and pH 8.4 buffer, which was more convenient to operate than the method reported by Stevens and Laughlin.

Molecular cloning and characterization of Y-box gene (Rpybx) from Manila clam and its expression analysis in different strains under low-temperature stress

Manila clam, Ruditapes philippinarum, is an economically important marine bivalve species. Y-box proteins are members of the cold shock proteins family and highly conserved from bacteria to humans. In this study, a novel Y-box gene (Rpybx) was cloned from the Manila clam and gene expression profiling was performed on three shell color strains (white, zebra and white zebra) and two wild populations (Southern and Northern) of R. philippinarum. The complete ORF length of Rpybx is 1367 bp, encoding 253 amino acids residues. Based on the amino acid sequence analysis and phylogenetic analysis, the Rpybx gene was identified as a member of the invertebrate Y-box proteins family. Rpybx has a similar tertiary structure to human Y-box protein YB-1. The Rpybx mRNA levels were analyzed by qPCR under acute and gradually varied cold stress. Under acute low-temperature stress, the expression of Rpybx mRNA in gills and hepatopancreas was significantly increased in all selected strains and populations (P < 0.05). The Northern population showed the lowest relative expression level of Rpybx. The expressions of Rpybx were greatly upregulated in gills and hepatopancreas of different stains and populations at 5 or -2°C under gradually varied temperature stress (P < 0.05). The results shed light on the biological function of the Rpybx gene in defending against low-temperature challenge and further exploring the molecular mechanism of cold tolerance and resistance in R. philippinarum.

Temperature effects on N2O production pathways in temperate forest soils

Nitrous oxide (N₂O) is an important greenhouse gas and contributes to stratospheric ozone depletion. Increasing temperature generally exerts a positive effect on soil N₂O production. However, not much is known on the temperature influence on individual N₂O production pathways. In this study, both laboratory ¹⁵N labelling experiments with an incubation temperature gradient (35 °C, 25 °C, 15 °C, 5 °C) and field ¹⁵N labelling experiments carried out in different seasons were conducted in Korean pine forest (KF) and Redwood coniferous forest (RF) soils. The results showed that the contribution of denitrification was positively correlated with temperature in KF and negatively correlated with temperature in RF, while their N₂O production rates via denitrification (N₂O_d) all declined with decreasing temperature. The contribution of autotrophic nitrification in KF ranged from 11% to 21%, while the contribution in RF significantly increased with decreasing temperature (P < 0.05). However, the N₂O production rates via autotrophic nitrification process (N₂O_a) were significantly and positively correlated with incubation temperature (P < 0.05). In addition, the contribution of heterotrophic nitrification to N₂O production showed a negative and positive relation with increasing temperature in KF and RF, respectively. Whereas, the N₂O production rates via heterotrophic nitrification (N₂O_h) showed a significantly positive correlation with temperature (P < 0.05), but a negative relation with gross heterotrophic nitrification rates. The results in the field experiments corresponded to the laboratory results, indicating that the methods applied in field experiments were suitable for the estimation and prediction of in situ N₂O production. The response of calculated N₂O production rates to seasonal temperature in KF during the year of 2015-2017 also confirmed the suitability of the field research methods. This novel in situ technique to determine N₂O production in temperate forest soils should be validated for other ecosystems.

An Antioxidant Role by Minocycline Via Enhancing the Activation of LKB1/AMPK Signaling in the Process of Cerebral Ischemia Injury

BACKGROUND

LKB1/AMPK signaling pathway, as a metabolic checkpoint, is involved in the pathogenesis of cerebral ischemia injury. Minocycline, a tetracycline derivative, protects against cerebral ischemia via reducing inflammation, oxidative stress, and apoptosis. The aim of the study was to evaluate the influence of minocycline on oxidative biomarkers and LKB1/AMPK signaling pathway in Wistar rats with focal cerebral ischemia injury and to clarify the neuroprotective mechanism of minocycline against focal cerebral ischemia injury.

METHODS

The focal cerebral ischemia injury of Wistar rats was established by inserting a thread into the left middle cerebral artery. 2,3,5-Triphenyltetrazolium chloride (TTC) staining was used to label infarct volume. The levels of MDA and LPO were measured with a biochemical assay. All other items were determined by Western blotting.

RESULTS

Minocycline decreased cerebral infarct volume, but had no effects on neurological scores. Minocycline improved the biological activity of GPx-1/2, GSS and GR, while limited the GGT1 activity in the hippocampus of cerebral ischemia-reperfusion rats. Minocycline also elevated the biological activity of SOD and counteracted lipid peroxidation. Minocycline enhanced the activity of both LKB1 and the levels of the three AMPK subunits in the hippocampus of cerebral ischemia-reperfusion rats.

CONCLUSION

Minocycline effectively inhibits oxidative stress via modulating antioxidative enzymes and activating the LKB1/AMPK signaling pathway in the process of acute cerebral infarct.

Comparison of the gut microbiota composition between the wild and captive Tibetan wild ass (Equus kiang)

Aims

The gut microbiota has a great effect on the health and nutrition of the host. Manipulation of the intestinal microbiota may improve animal health and growth performance. The objectives of our study were to characterize the faecal microbiota between wild and captive Tibetan wild asses and discuss the differences and their reasons.

Methods and Results

Through high‐throughput sequencing of the 16S rRNA V4‐V5 region, we studied the gut microbiota composition and structure of Tibetan wild asses in winter, and analysed the differences between wild and captive groups. The results showed that the most common bacterial phylum in Tibetan wild ass faeces samples was Bacteroidetes, while the phylum Firmicutes was dominant in captive Tibetan wild ass faecal samples. The relative abundance of Firmicutes, Tenericutes and Spirochaetes were significantly higher (P < 0·01) than in the wild groups.

Conclusions

Captivity reduces intestinal microbial diversity, evenness and operational taxonomic unit number due to the consumption of industrial food, therefore, increasing the risk of disease prevalence and affecting the health of wildlife.

Significance and Impact of the Study

We studied the effect of the captive environment on intestinal micro‐organisms. This article provides a theoretical basis for the ex‐situ conservation of wild animals in the future.

Importance of matching soil N transformations, crop N form preference, and climate to enhance crop yield and reducing N loss

The preferential uptake of nitrogen (N) by plant species is generally considered to be tightly associated with soil N transformation characteristics and climatic conditions. In the present study, the yield, N recovery, and N balance of wheat (an NO₃^--preferring crop) and rice (an NH₄⁺-preferring crop) planted in two sites with significantly different soil N transformations and precipitation were compared to test the connections among soil N transformations, species-specific N preferences, crop yield, N use efficiency (NUE), N loss, and climate. Nitrogen recoveries of ¹⁵N applied as either an NH₄⁺ or NO₃^- based fertilizer in crops and soil were determined, and N losses were calculated using the ¹⁵N balance. The results indicated that the match (or mismatch) of crop N preference, soil N transformation characteristics, and climate conditions could significantly affect the crop yield, recovery, and loss of applied ¹⁵N. A crop preferring NH₄⁺ (e.g., rice) planted in soil with low nitrification and low pH tended to have a higher yield and NUE, and a lower N loss compared with plants growing in soil characterized by a higher nitrification rates. In contrast, NO₃^--preferring crops (e.g. wheat) planted in soil with higher nitrification rates and lower precipitation achieved a higher yield and lower N loss than those planted in acid soil with a lower nitrification rate and higher precipitation. Replacement of ammonium N fertilizer with nitrate N fertilizer improved the NUE for NO₃^--preferring crops (wheat) planted in arid and semi-arid regions, but not in humid regions because of the mobility of NO₃^-. Thus, a good match of crop N preference, soil N transformation characteristics, and climate conditions is critical to enhance crop yield and reduce N loss. This intimate connection needs to be taken into consideration in terms of the choice of crop species and N fertilizer type to optimize N fertilization management.

[Application of pegylated recombinant human granulocyte colony-stimulating factor to prevent chemotherapy-induced neutropenia in patients with lymphoma: a prospective, multicenter, open-label clinical trial]

目的

评价聚乙二醇化重组人粒细胞刺激因子（PEG-rhG-CSF）预防淋巴瘤患者化疗后发生中性粒细胞减少症的有效性和安全性。

方法

本研究为多中心、开放、单臂、Ⅳ期临床试验。纳入410例淋巴瘤患者接受多周期化疗并预防性使用PEG-rhG-CSF。主要观察患者各化疗周期Ⅲ/Ⅳ度中性粒细胞减少症和发热性中性粒细胞减少（FN）的发生率，同时观察患者整个化疗期间抗生素的使用率。

结果

①410例患者中，违背入选标准8例（1.95%），失访35例（8.54%），发生不良事件19例（4.63%），出现符合终止研究标准者12例（2.93%），疾病进展或复发15例（3.66%），故最终321例（78.29%）进入符合方案集。②在第1~4个治疗周期，初级预防给予PEG-rhG-CSF后，Ⅳ度中性粒细胞减少症的发生率分别为19.14%（49/256）、12.50%（32/256）、12.18%（24/197）、13.61%（20/147），FN的发生率分别为3.52%（9/256）、0.39%（1/256）、2.54%（5/197）、2.04%（3/147）；次级预防给药后，Ⅳ度中性粒细胞减少症的发生率从61.54%（40/65）降至16.92%（11/65）、18.46%（12/65）、20.75%（11/53），FN的发生率从16.92%（11/65）降至1.54%（1/65）、4.62%（3/65）、3.77%（2/53）。③整个化疗期间接受抗生素治疗的受试者比例为34.39%（141/410）。④与PEG-rhG-CSF相关的不良事件发生率为4.63%（19/410），最常见的不良反应为骨痛[3.90%（16/410）]、乏力（0.49%）和发热（0.24%）。

结论

在淋巴瘤患者化疗过程中，预防性使用PEG-rhG-CSF能够有效降低化疗过程中Ⅲ/Ⅳ度中性粒细胞减少症和FN的发生率，确保淋巴瘤患者接受标准剂量化疗，提高治愈率。

[The effect of WT1 expression on the prognosis of allogeneic hematopoietic stem cell transplantation in acute leukemia]

Objective: To study the effect of WT1 expression on the prognosis of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in acute leukemia (AL) and its significance as molecular marker to dynamically monitor minimal residual disease (MRD) . Methods: Retrospectively analyzed those AL patients who underwent allo-HSCT in the First Hospital Affiliated to Zhejiang University School of Medicine during Jan 2016 to Dec 2017, a total number of 314 cases, 163 males and 151 females, median age was 30 (9-64) years old. Comparing the difference of WT1 expression at diagnosed, pre-HSCT and after HSCT. Using the receiver operating characteristic (ROC) curve to determine the WT1 threshold at different time so as to predict relapse. The threshold of WT1 expression before transplantation was 1.010%, within 3 months after HSCT was 0.079% and 6 months after HSCT was 0.375%. According to these thresholds, WT1 positive patients were divided into low expression groups and high expression groups. Analyzed the relationship between overall survival (OS) , disease-free survival (DFS) , cumulative incidence of relapse (CIR) and WT1 expression. Results: The OS and DFS of high expression group pre-HSCT were lower than low expression group [69.2% (9/13) vs 89.1% (57/64) , χ(2)=4.086, P=0.043; 53.8% (7/13) vs 87.5% (56/64) , χ(2)=9.766, P=0.002], CIR was higher than low expression group [30.8% (4/13) vs 7.8% (5/64) , P=0.017]. There was no significant difference of OS and DFS between high expression and low expression group of 3 months after HSCT (P=0.558, P=0.269) . The OS and DFS of high expression group of 6 months after transplantation were both lower than low expression group (P=0.049, P=0.035) . Multivariate analysis showed that WT1>0.375% when 6 months after transplantation was the only independent prognostic factor for shorter DFS (P=0.022) . There was no statistically significant difference in CIR between the high-expression group and the low-expression group 3 months after transplantation and 6 months after transplantation (P=0.114, P=0.306) . Conclusion: High expression of WT1 before and after HSCT was an adverse prognosis factor. It is of clinical practical value to use WT1 as a transplant recommendation index for patients with acute leukemia and as a marker to monitor MRD dynamically.

Abstract P4-12-07: Patients' preferences for postmenopausal hormone receptor-positive (HR+), human epidermal growth factor receptor 2 negative (HER2-) advanced breast cancer treatments in Japan

Background: The objective of this study was to identify factors that affect preferences for treatment of breast cancer (BC) patients in Japan and understand their relative importance. Also this study explored whether patients' sociodemographic and clinical characteristics would affect patient preference in choice of treatment. Methods: A questionnaire for discrete choice experiment (DCE) was developed with five attributes, progression free survival (PFS), incidence of diarrhea (IOD), frequency of diarrhea (FOD) which represents the increase in the number of stools per day than usual, duration of diarrhea (DOD) and route and frequency of administration (RFA) referring MONARCH 2, a global phase III study for abemaciclib plus fulvestrant versus placebo plus fulvestrant in patients with HR+/HER2− advanced BC. Each questionnaire was composed of nine choice sets and each choice set contained those five attributes with different levels. Postmenopausal and HR+ BC patients in Japan who recruited from a patient panel were asked to choose one treatment alternative in each choice set. Conditional logit model was used to identify relative preferences of each attribute. The preference weights were evaluated with βcoefficient and standard error. In addition, conditional logit model including patient-specific covariates, such as patient characteristics (age, employment status, age of children and marital status) and clinical characteristics (experience of relapse or metastasis and with/without hormone sensitivity), was used to identify factors that affect patient preference in choice of treatment. Results: Of 302 respondents recruited, 258 had valid responses and the rest had inappropriate answers for the validity testing choice set. The mean age (SD) was 56.7(6.7), 47.7% had paid employment, median duration since diagnosis was 5.1 years and 98.1% had experienced hormonal therapy. According to the absolute magnitude of coefficients, when the FOD is 6, the order of attributes' relative importance was the following: PFS, DOD, FOD, IOD, RFA. However when the FOD becomes 9, FOD was the most important attribute for patients. All tested attributes were statistically significant (p&lt;.0001) on their preference in choice of treatment. When patient-specific covariates were included in the model, the patients who have had experience of relapse or metastasis showed the strongest preference for the longest PFS of 16 months and the patients who were 45 to 59 years old showed the weakest preference for the highest FOD of 9. Conclusions: Postmenopausal and HR+ BC patients in Japan showed preference for treatments which can extend PFS even with the potentiality of Grade 2 diarrhea by the grading of Common Terminology Criteria for Adverse Events v4.0. Prevention of diarrhea to make it Grade 2 or lower may maintain patients' motivation for the treatment which can extend PFS. This study also showed that patients' sociodemographic and clinical characteristics tend to affect patients' treatment choices. It will be important to choose treatments with considering patients' characteristics such as their life style, age and therapeutic experience.

Citation Format: Omori Y, Enatsu S, Cai Z, Ishiguro H. Patients' preferences for postmenopausal hormone receptor-positive (HR+), human epidermal growth factor receptor 2 negative (HER2-) advanced breast cancer treatments in Japan [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-12-07.

Response of denitrification in paddy soils with different nitrification rates to soil moisture and glucose addition

Denitrification is one of the most important N loss pathways in paddy soil. The nitrification rate is a key natural feature for controlling denitrification N loss in paddy soil. However, the relationship between nitrification and denitrification under different conditions in paddy soil remains unknown. By using ¹⁵N tracing, we investigated the response of denitrification loss to soil moisture and glucose addition in six paddy soils, whose net nitrification rates ranged from 0.36 mg N kg^-1 day^-1 to 5.72 mg N kg^-1 day^-1. The soils were amended with or without glucose to simulate root exudates at rates of 100 mg kg^-1 of soil and incubated under either 60% water holding capacity (WHC) or flooded (2 cm depth) at 25 °C for 15 days. Denitrification loss was calculated by the unrecovered ¹⁵NH₄⁺. The results showed that the soil nitrification rate significantly affected the N recovery form and denitrification loss of the applied ¹⁵N. NH₄⁺ was the main recovered N form of the applied ¹⁵N in soil with a low nitrification rates. Denitrification losses were higher in the high nitrification rate soil than soil with low nitrification rate in all treatments. The correlation between denitrification and nitrification rates was well fit by Michaelis-Menten kinetics during the incubation, irrespective of soil moisture and glucose addition, and the R² ranged from 0.801 to 0.977 (P < 0.05). Glucose addition did not stimulate denitrification under either 60% WHC or flooded conditions. The results showed that nitrification rate, rather than labile organic supply, controlled denitrification in paddy soil.