RN Treatment Research Articles

Enhancing wheat yield and nitrogen use efficiency in the Huang‐Huai‐Hai region of China: Insights from root biomass and nitrogen application responses

AbstractWheat yield and nitrogen use efficiency (NUE) have improved simultaneously with the genetic development of wheat varieties. However, wheat selection is carried out routinely in N‐rich field conditions, with breeding progress limited under low soil available nitrogen. Thus, we performed a 2‐year field investigation using eight milestone winter wheat varieties released between 1947 and 2017 in the Huang‐Huai‐Hai region of China with two N applications—normal (CK; 220 kg N ha−1) and reduced (RN; 110 kg N ha−1)—in Shaanxi, China, to examine changes in wheat yield, NUE, water use efficiency (WUE) and root biomass. Our findings revealed average annual yield increases of 49.615 kg ha−1 and 36.905 kg ha−1 under CK and RN, respectively. Notably, the NUE trend mirrored yield, increasing with the release year of wheat varieties, with average annual increases in NUE of 0.192 and 0.336 kg kg−1 under CK and RN, respectively. In the RN treatment, N uptake efficiency (UPE) increased with year of release, while N utilization efficiency (UTE) had no significant relationship. In the CK treatment, UTE increased with year of release, while UPE had no significant relationship. Across the 2‐year experiment, surface root biomass (0–20 cm layer) increased with year of release under CK but had no relationship under RN, while deep root biomass (20–200 cm layer) decreased with year of release under CK and increased under RN. The roots of modern wheat varieties responded better to soil nitrogen levels and produced higher yields, NUE and WUE than earlier varieties by adjusting root biomass distribution in soil.

Independent, but not co-supplementation, with nitrate and resveratrol improves glucose tolerance and reduces markers of cellular stress in high-fat-fed male mice.

Independent supplementation with nitrate (NIT) and resveratrol (RSV) enriches various aspects of mitochondrial biology in key metabolic tissues. Although RSV is known to activate Sirt1 and initiate mitochondrial biogenesis, the metabolic benefits elicited by dietary nitrate appear to be dependent on 5'-adenosine monophosphate-activated protein kinase (AMPK)-mediated signaling events, a process also linked to the activation of Sirt1. Although the benefits of individual supplementation with these compounds have been characterized, it is unknown if co-supplementation may produce superior metabolic adaptations. Thus, we aimed to determine if treatment with combined +NIT and +RSV (+RN) could additively alter metabolic adaptations in the presence of a high-fat diet (HFD). Both +RSV and +NIT improved glucose tolerance compared with HFD (P < 0.05); however, this response was attenuated following combined +RN supplementation. Within skeletal muscle, all supplements increased mitochondrial ADP sensitivity compared with HFD (P < 0.05), without altering mitochondrial content. Although +RSV and +NIT decreased hepatic lipid deposition compared with HFD (P < 0.05), this effect was abolished with +RN, which aligned with significant reductions in Sirt1 protein content (P < 0.05) after combined treatment, in the absence of changes to mitochondrial content or function. Within epididymal white adipose tissue (eWAT), all supplements reduced crown-like structure accumulation compared with HFD (P < 0.0001) and mitochondrial reactive oxygen species (ROS) emission (P < 0.05), alongside reduced adipocyte cross-sectional area (CSA) (P < 0.05), with the greatest effect observed after +RN treatment (P = 0.0001). Although the present data suggest additive changes in adipose tissue metabolism after +RN treatment, concomitant impairments in hepatic lipid homeostasis appear to prevent improvements in whole body glucose homeostasis observed with independent treatment, which may be Sirt1 dependent.

Effects of reduced nitrogen application on soil aeration and root nodule growth of relay strip intercropping soybean

<p id="C3">To study the effects of planting system and nitrogen application rate on soybean soil aeration environment and nodulation and nitrogen fixation, we adopted a two-factor split area experiment design, with the main area of planting pattern [soybean monoculture (SS), maize/soybean relay strip intercropping (MS)], and the sub-regions of different nitrogen application rates [no nitrogen application (NN: 0 kg hm^-2), reduced nitrogen application (RN: 45 kg hm^-2), and constant nitrogen application (CN: 60 kg hm^-2)]. The dynamic changes of soil O₂ content and soil respiration rate during soybean growth period was monitored, the differences of soil water-stable aggregates, bulk density, and porosity of each treatment were analyzed, and the variation characteristics of nodulation amount and nitrogen fixation capacity during soybean growth period were discussed. Two years’ data showed that, compared with monoculture soybean, relay strip intercropping soybeans increased soil O₂ content, the percentage of aggregates with a particle size &gt; 2 mm, significantly increased soil porosity and soil respiration rate during the late growth period in soybean; reduced the percentage of aggregates with a particle size of &lt; 1 mm and soil porosity. There was no significant difference in the dry weight of nodules at R5 stage, but the number of nodules was significantly increased by 39.9%. Nitrogenase activity and nitrogen fixation potential were also significantly higher than those of monocrops. Among the various nitrogen application rates, the soil O₂ content, the percentage content of 0.25-1.00 mm particle size, and the soil respiration rate of relay strip intercropping soybean were the highest in RN treatment. Nitrogen application decreased the percentage content of water-stable aggregates with particle size &lt; 0.25 mm and soil bulk density; nitrogen application significantly inhibited the nodulation amount, nitrogenase activity and nitrogen fixation potential of monoculture soybean in the early stage, but the inhibitory effect of nitrogen fertilizer was alleviated at R5 stage. Reduced nitrogen application increased nodulation at the late stage of relay strip intercropping soybean, and it could significantly enhance the nitrogenase activity and nitrogen fixation potential of soybeans during the growth period. Relay strip intercropping soybean combined with reduced nitrogen application promoted the formation of large aggregates, increased soil porosity, improved soybean soil aeration environment, maintained higher soil O₂ content, promoted soil respiration, and facilitated the nodulation and nitrogen fixation of soybean at later stages.

Response of N2O emissions to N fertilizer reduction combined with biochar application in a rain-fed winter wheat ecosystem

Optimizing nitrogen application rate and biochar application is an important management measure to reduce N loss and increase yield in farmlands. However, the combined effects and mechanisms of different biochar amendment rates with N fertilizer reduction on soil N2O emissions have not been fully evaluated in rain-fed areas. Therefore, a three-season field trial was conducted in a winter wheat field including six treatments: no fertilizer (N0), conventional N fertilizer (CN: 226.5 kg N ha-1, 100%), reduced N fertilizer (RN: 140.3 kg N ha-1, 62%), RN+ 5 t ha-1 biochar (RNB5), RN+ 10 t ha-1 biochar (RNB10), and RN+ 20 t ha-1 biochar (RNB20). Our results showed that the cumulative N2O emissions ranged from 0.35 kg N ha-1 to 2.33 kg N ha-1 in all fertilizer treatments, of which 45.29–90.32% mainly occurred after N fertilizer application. RN treatment reduced N2O emissions compared with CN treatment. In comparison with the RN, RNB5 treatment significantly (P < 0.05) decreased the cumulative N2O emissions, owing to low inorganic N contents and increase in the abundance of nosZ gene. No significant variation in N2O emissions was found between RNB10 and RN treatments. Whereas, N2O emissions significantly (P < 0.05) increased by 18.42% in 2016–2017 season in RNB20 treatment. Soil moisture, NH4+-N and NO3--N contents, and nirS,nirK, and nosZ abundance were higher on RNB20 treatment than other treatments and showed significant positive correlation with N2O emissions (P < 0.05). In addition, RNB10 and RNB20 treatments significantly (P < 0.05) improved the mean crop N uptake and yield, compared with RN and RNB5 treatments, while no significant variation was found between RNB10 and RNB20 treatments. Biochar addition combined with N reduction reduced yield-scaled N2O emissions by 7.57–12.93%. Given the high production efficiency and sustainability, N fertilizer reduction (140.3 kg ha-1) combined with biochar applied at 10 t ha-1 resulted in increasing yield while minimizing N2O emissions in a rain-fed winter wheat ecosystem.

Summer fallow straw mulching and reducing nitrogen fertilization: A promising practice to alleviate environmental risk while increasing yield and economic profits of dryland wheat production

Drought and excessive nitrogen (N) fertilization impair the sustainability of dryland wheat production in northern China. These problems could potentially be addressed by combining mulching during the summer fallow period and reducing N fertilization rate to the recommended levels. Thus, we assessed this possibility in a three-year in-situ field experiment with four treatments: farmers’ customary fertilization (CF) and reduced N fertilization (RNF) with no mulching during the summer fallow period (CF and RNF, respectively), and RNF with plastic film mulch (PM) and straw mulch (SM) in the summer fallow period (i.e., RNF + PM and RNF + SM, respectively). We evaluated the effects of various treatments on wheat grain yield, economic profit and environmental risk. The average grain yields of the CF, RNF, RNF + PM and RNF + SM treatments were 5932, 5364, 5950 and 6240 kg ha−1, respectively. In addition, the average and yearly soil water storage at pre-seeding were significantly higher for the RNF + SM and RNF + PM treatments than the RNF treatment by 23% and 18%, respectively. Moreover, the average increases in soil water storage during the summer fallow period were significantly higher for the RNF + SM and RNF + PM treatments than the RN treatment, by 63% and 44%, respectively. Both the average and yearly soil accumulated temperatures during the summer fallow period were significantly higher for the CF, RNF and RNF + PM treatments than the RNF + SM treatment. The NO3−1-N leaching occurred under the CF treatment during the summer fallow period, but not under the RNF, RNF + PM and RNF + SM treatments. The RNF + SM treatment resulted in a significantly higher economic profit and significantly lower greenhouse gas intensity (GHGI) than the CF, RNF and RNF + PM treatments. Thus, mulching with straw during the summer fallow period and reducing N fertilization appears to be an environment-friendly strategy for dryland wheat production in northern China.

Application of enhanced-efficiency nitrogen fertilizers reduces mineral nitrogen usage and emissions of both N2O and NH3 while sustaining yields in a wheat-rice rotation system

The application of nitrification and urease inhibitors with urea can increase the residence time of ammonium (NH4+) in soils and thus reduce nitrogen (N) losses to the environment. We therefore hypothesized that these inhibitors would perform better in enhancing crop yield and lowering nitrous oxide (N2O) and ammonia (NH3) emissions in rice preferring NH4+ than in wheat preferring nitrate (NO3–). Additionally, a biostimulant (BS) when co-applied with urea would improve N uptake and thus reduce N loss as well. Thereby, the objective of this two-year field experiment was to evaluate the effects of urease inhibitor (UI) N-(n-butyl) thiophosphorictriamide (NBPT), the new nitrification inhibitor (NI) 3,4-dimethylpyrazole succinic acid (DMPSA), dual inhibitors (UI + NI) (NBPT + DMPSA), and a BS on crop yield and soil N2O and NH3 emissions in a wheat-rice rotation system. Treatments comprised no N fertilizer (Zero-N), urea under conventional practice (CN), and urea at a reduced rate by 20% either alone (RN) or combined with UI, NI, UI + NI, or BS. Averagely, RN treatment decreased N2O and NH3 emissions by 29.9% and 21.7%, respectively, but reduced grain yield and N use efficiency by 13.1% and 16.3%, respectively, compared with the CN treatment, although not always significantly. However, the combined use of RN and UI, NI, UI + NI, or BS resulted in comparable grain yield and N use efficiency but with lesser N2O and NH3 emissions by 56.4% and 36.1%, respectively averaged across treatments compared with CN treatment. We demonstrated that both inhibitors performed better in reducing N2O and NH3 emissions in rice than in wheat. Overall, we propose that the application of NBPT, DMPSA, and BS could be an effective strategy to mitigate gaseous N pollution while sustaining crop yields in the wheat-rice rotation system.

Response of soil N2O emission and nitrogen utilization to organic matter in the wheat and maize rotation system

The appropriate nitrogen (N) fertilizer regulator could increase N utilization of crops and reduce N losses in the North China Plain. We investigated the effects of reduced inorganic-N rate combined with an organic fertilizer on nitrous oxide (N2O) emissions in winter wheat and summer maize rotation system. Simultaneously studied the effect of different treatments on N use efficiency (NUE), N balance and net income. After reducing the amount of nitrogen fertilizer in the wheat-corn rotation system, the results showed that the cumulative emission of soil N2O from the RN40% + HOM [40% of RN (recommended inorganic-N rate) with homemade organic matter] treatment was 41.0% lower than that of the RN treatment. In addition, the N production efficiency, agronomic efficiency, and apparent utilization were significantly increased by 50.2%, 72.4% and 19.5% than RN, respectively. The use of RN40% + HOM resulted in 22.0 and 30.1% lower soil N residual and N losses as compared with RN. After adding organic substances, soil N2O cumulative emission of RN40% + HOM treatment decreased by 20.9% than that of the HAN (zinc and humic acid urea at the same inorganic-N rate of RN) treatment. The N production efficiency, N agronomic efficiency and NUE of RN40% + HOM treatment were 36.6%, 40.9% and 15.3% higher than HAN’s. Moreover, soil residual and apparent loss N were 23.3% and 18.0% less than HAN’s. The RN40% + HOM treatment appears to be the most effective as a fertilizer control method where it reduced N fertilizer input and its loss to the environment and provided the highest grain yield.

Improvement of Hypertriglyceridemia by Roasted Nelumbinis folium in High Fat/High Cholesterol Diet Rat Model.

Hypertriglyceridemia is a condition characterized by high triglyceride levels and is a major risk factor for the development of cardiovascular diseases. The present study was designed to investigate the inhibitory effect of roasted Nelumbinis folium (RN), which is a medicinal substance produced by heating lotus leaves, on lipid metabolism in high fat/cholesterol (HFC) diet-induced hypertriglyceridemia. Except for those in the control group, Sprague–Dawley rats were fed an HFC diet for four weeks to induce hypertriglyceridemia. During the next nine weeks, the control, regular diet; HFC, HFC diet, FLU, fluvastatin (3 mg/kg/day); RNL, RN (100 mg/kg/day); RNH, RN (200 mg/kg/day) were orally administered together with the diet, and the experiments were conducted for a total of 13 weeks. The weight of the epididymal adipose tissue, liver, and heart of rats in the HFC diet group significantly increased compared to those in the control group but improved in the RN-treated group. It was also confirmed that vascular function, which is damaged by an HFC diet, was improved after RN treatment. The levels of insulin, glucose, triglycerides, total cholesterol, and low-density lipoprotein increased in the HFC diet group compared to those in the control group, while the administration of RN attenuated these parameters. In addition, the administration of RN significantly reduced the gene expression of both LXR and SREBP-1, which indicated the inhibitory effect of the biosynthesis of triglycerides caused by RN. The results indicated that RN administration resulted in an improvement in the overall lipid metabolism and a decrease in the concentration of triglycerides in the HFC diet-induced rat model of hypertriglyceridemia. Therefore, our findings suggest that the RN can be a candidate material to provide a new direction for treating hypertriglyceridemia.

The effect of nutrient restriction and syndecan-4 or glypican-1 knockdown on the differentiation of turkey pectoralis major satellite cells differing in age and growth selection

Skeletal muscle growth is mediated by the proliferation and differentiation of satellite cells, whose activity is affected by both nutrition and the expression of syndecan-4 and glypican-1. Previous research has not addressed if there is an interactive effect of nutrition with the expression of syndecan-4 and glypican-1. Thus, the objective of the current study was to determine if the response of satellite cells to nutrient restriction was altered by syndecan-4 or glypican-1 knockdown and if age and growth selection are factors. Satellite cells were isolated from pectoralis major muscle of 1-day, 7-wk, and 16-wk-old turkeys selected for increased 16-wk body weight (F line) and the randombred control (RBC2) line from which the F line was selected. Syndecan-4 or glypican-1 expression was knocked down in both lines using small interfering RNAs along with nutrient restriction of 0 or 20% of the standard cell culture medium either applied during proliferation with subsequent normal differentiation medium (RN) or during differentiation with preceding normal proliferation medium (NR). For both lines, nutrient restriction and syndecan-4 or glypican-1 knockdown had an independent and additive effect on satellite cell differentiation at 72h of differentiation except for 1 d satellite cells. The 1 d satellite cell differentiation was increased by RN treatment, but when combined with syndecan-4 or glypican-1 knockdown, the increase in differentiation was negated. At 48h of differentiation, syndecan-4 knockdown in 7 and 16 wk satellite cells and glypican-1 knockdown in 7 wk cells cancelled the effect of the RN treatment, but enhanced the effect of NR treatment at 24h of differentiation. Growth selection had little effect on the interaction between nutrient restriction and syndecan-4 or glypican-1 knockdown. Taken together, these data demonstrate that the satellite cell response to nutrition is dependent on the expression of syndecan-4 and glypican-1 in an age-dependent manner with growth selection having little impact.

The effect of nutrient restriction on the proliferation and differentiation of turkey pectoralis major satellite cells differing in age and growth rate

Myogenic satellite cells are critical for posthatch muscle growth, and their activity is sensitive to nutritional regime during the immediate posthatch period. The objective of the current study was to determine if the response of satellite cells to nutrient restriction was dependent on bird age and/or growth rate. Satellite cells were isolated from the pectoralis major (p. major) muscle of 1-d, 7-wk, and 16-wk-old turkeys selected for increased body weight at 16 wk of age (F line) and the randombred control (RBC2) line from which the F line was selected. Nutrient restriction of 0, 5, 10, 20, and 40% of the standard cell culture medium was applied during proliferation with subsequent normal differentiation medium (RN) or during differentiation with preceding normal proliferation medium (NR). Satellite cell proliferation and differentiation decreased with nutrient restriction for all treatment regimens and ages, except for 1-d cell differentiation with the RN treatment, which increased with nutrient restriction. Interestingly, after 24h of a 5% nutrient restriction during the RN treatment, proliferation increased for 1-d and 7-wk cells. Additionally, after 24h of 5, 10, and 20% nutrient restriction during the NR treatment, differentiation increased for 1-d and 7-wk cells. The 16-wk cells did not exhibit this response to any treatment regimen. Growth rate had little effect on satellite cell response to nutrient restriction. In this study, satellite cells differentially responded to nutrient restriction depending on age, as well as duration and timing of the nutrient restriction. These data suggest that it is necessary to optimize diets throughout a bird's life to maximize satellite cell activity and p. major muscle growth.

Ribes nigrum L. Prevents UVB-mediated Photoaging in Human Dermal Fibroblasts: Potential Antioxidant and Antiinflammatory Activity.

Black currants (Ribes nigrum L, RN) are known as a "super fruit" to possess for their many potential health benefits such as the alleviation of oxidative stress-related disorders. However, little skin photoaging-related research has been done on the use of this agent. In the present study, we investigated the protective effects of RN in UVB-irradiated human dermal fibroblasts (NHDFs). RN treatment in UVB-irradiated skin models alleviated UVB-mediated photoaging through several mechanisms: Treatment with RN downregulated MAPK-related signaling models, such as those of activation protein 1 (AP-1) and nuclear factor kappa B (NF-κB). In addition, phase II gene heme oxygenase-1 (HO-1) was modulated by the increase in nuclear factor erythroid 2-related factor 2 (Nrf2) in the nuclear, and finally, transforming growth factor TGF-β was upregulated in vitro. Further study indicated that UVB-induced production of MMP-1 and IL-6 could be inhibited by PD 98059 (an inhibitor of ERK) and SP600125 (an inhibitor of JNK). Thus, RN improved the expression of type I procollagen and inhibited UVB-induced MMP-1 and IL-6 secretion through inactivating MAPK cascades. Therefore, RN is a suitable target for further investigation as an antiphotoaging agent and may have applications in the skincare industry.

Rotatinuous stocking: A grazing management innovation that has high potential to mitigate methane emissions by sheep

To test the hypothesis that the best sward structure in the grazing management strategy based on animal behaviour, called ?Rotatinuous? stocking, results in higher nutrient intake and lower methane emission and intensity by sheep grazing Italian ryegrass pastures, two grazing management strategies were studied: the traditional rotational stocking (RT) with pre- and post-grazing sward target heights of 25 and 5 cm, respectively and, ?Rotatinuous? stocking (RN) with pre- and post-grazing sward target heights of 18 and 11 cm, respectively. Male castrated sheep were used. The experiment was carried out in 2014 and 2015 in southern Brazil. The experimental design was a randomized complete block with four replicates. The RN treatment had better herbage chemical composition in terms of quality than that of the RT treatment, with greater (P < 0.05) crude protein and lower neutral and acidic detergent fibre. The ideal sward structure and greater chemical composition of Italian ryegrass pastures found under RN treatment resulted in greater herbage digestibility and intake of organic matter and metabolizable energy by grazing sheep than under the RT treatment. Our study highlights that management is the key strategy to reduce the environmental impact of grazing through lower CH4 emissions in livestock grazing systems. Rotatinuous: stocking was the more efficient grazing management strategy for mitigation of CH4 emissions and intensity by grazing sheep, with 64% less CH4 production per area and 170% less CH4 emission per unit of animal product when compared to the RT treatment.

Snake Venom Disintegrin Inhibits the Activation of Toll-Like Receptors and Alleviates Sepsis through Integrin alphaVbeta3 Blockade.

Bacterial infection-induced sepsis is the leading cause of septic inflammatory disease. Rhodostomin (Rn), a snake venom disintegrin, was previously reported to interact with the αVβ3 integrin and the TLR4 on phagocyte in attenuating LPS-induced endotoxemia. In this report, we further evaluated the effects of Rn on TLR2-activated monocytes and its in vivo efficacy. Rn effectively suppressed the adhesion, migration, and cytokine release of Pam3CSK4-activated THP-1 cells. Rn specifically bound to integrin αVβ3 of TLR2-activated THP-1. Integrin αV and Akt siRNA transfection both restrained Pam3CSK4-elicited cytokine release. Rn decreased the Pam3CSK4-induced phosporylation of MAPKs, degradation of IκB and activation of FAK, Akt, c-Src and Syk. The Pam3CSK4-induced translocation of MyD88, a central adaptor of TLR2, to the cell membrane was also inhibited by Rn treatment. In the polymicrobial inflammatory caecal ligation and puncture model, Rn significantly reduced pro-inflammatory cytokine and chemokine release, alleviated tissue injury and elevated survival rate in vivo. Taken together, in addition to inhibiting the activation of TLR4, Rn exhibits anti-inflammatory activity through antagonizing the activation of phagocytes and interrupting the crosstalk between αVβ3 and TLR2-dependent signaling pathways.

Effects of biochar on nitrous oxide and nitric oxide emissions from paddy field during the wheat growth season

Agricultural activities are an important source of atmospheric nitrous oxide (N2O). Excess nitrogen (N) fertilization in the Taihu Lake region, southeast China, has resulted in a series of environmental issues such as N2O emissions and water body eutrophication. Optimal fertilization can reduce the loss of surplus N with a penalty of no or low yield. The conversion of plant residues to biochar is an attractive strategy for mitigating atmospheric carbon dioxide emissions and for enhancing carbon storage in soil. A field experiment was conducted to investigate the effect of biochar on N2O emissions, crop yield, and global warming potential (GWP). Five treatments were conducted with four replicates: no nitrogen fertilizer (Control), locally conventional N fertilizer (RN), optimal N fertilizer (ON), optimal N fertilizer plus low amount of biochar [3.75 t ha−1; (ONC1)], and optimal N fertilizer plus high amount of biochar [7.50 t ha−1; (ONC2)]. Results showed that both N2O and NO emissions increased exponentially with the N fertilizer application rate during the wheat growth season, and cumulative N2O emissions were significantly (P < 0.05) reduced in the ON treatment. Biochar amendment at 3.75 and 7.50 t ha−1 did not notably reduce N2O emissions. A significant negative correlation was observed between N2O flux and the soil water-filled pore space (WFPS) in biochar amendment, and the NO/N2O ratio was almost lower than 1, except for tillering fertilization when the soil WFPS was lower, indicating that N2O was primarily produced by denitrification. The GWP was significantly mitigated in the ON treatment compared with the RN treatment, which was significantly lower in the biochar treatment (P < 0.05). The greenhouse gas intensity (GHGI) also decreased from 0.039 to 0.031 kg CO2-eq kg−1 yield after biochar addition. GWP and GHGI results indicated that the application of biochar could significantly mitigate GWP compared with the ON treatment. Our results suggest that the application of biochar slightly reduced N2O emission, which might contribute to promote the reduction N2O to N2. Optimal N fertilization, especially, combined with biochar will exercise a greater effect for mitigating global warming.

Combined inhibition of the BMP pathway and the RANK-RANKL axis in a mixed lytic/blastic prostate cancer lesion

The purpose of this study was to investigate the influence of combined inhibition of receptor activator of nuclear factor kappa-B ligand (RANKL) and bone morphogenetic protein (BMP) activity in a mixed lytic/blastic prostate cancer lesion in bone. Human prostate cancer cells (C4 2b) were injected into immunocompromised mice using an intratibial injection model to create mixed lytic/blastic lesions. RANK-Fc, a recombinant RANKL antagonist, was injected subcutaneously three times a week (10 mg/kg) to inhibit RANKL and subsequent formation, function and survival of osteoclasts. Inhibition of BMP activity was achieved by transducing prostate cancer cells ex vivo with a retroviral vector expressing noggin (retronoggin; RN). There were three treatment groups (RANK-Fc treatment, RN treatment and combined RN and RANK-Fc treatment) and two control groups (untreated control and empty vector control for the RN treatment group). The progression of bone lesion and tumor growth was evaluated using plain radiographs, hindlimb tumor size, 18F-Fluorodeoxyglucose and 18F-fluoride micro PET-CT, histology and histomorphometry. Treatment with RANK-Fc alone inhibited osteolysis and transformed a mixed lytic/blastic lesion into an osteoblastic phenotype. Treatment with RN alone inhibited the osteoblastic component in a mixed lytic/blastic lesion and resulted in formation of smaller osteolytic bone lesion with smaller soft tissue size. The animals treated with both RN and RANK-Fc demonstrated delayed development of bone lesions, inhibition of osteolysis, small soft tissue tumors and preservation of bone architecture with less tumor induced new bone formation. This study suggests that combined inhibition of the RANKL and the BMP pathway may be an effective biologic therapy to inhibit the progression of established mixed lytic/blastic prostate cancer lesions in bone.

Root zone soil nitrogen management to maintain high tomato yields and minimum nitrogen losses to the environment

Greenhouse field experiments on tomato were carried out at Shouguang, Shandong province, over four double cropping seasons between 2004 and 2008 in order to understand the effects of manipulating root zone N management (RN) on fruit yields, N savings and N losses under conventional furrow irrigation. About 72% of the chemical N fertilizer used in conventional treatment (CN) inputs could be saved using the RN treatment without loss of yield. The cumulative fruit yields were significantly higher in the RN treatment than in the CN treatment. Average seasonal N from irrigation water (118 kg N ha −1), about 59% of shoot N uptake, was the main nitrogen source in treatments with organic manure application (MN) and without organic manure or nitrogen fertilizer (NN). N losses in the RN treatment were lowered by 54% compared with the CN treatment. Lower N losses were found in the MN and NN treatments due to excessive inputs of organic manure and fruit yields were consequently substantially affected in the NN treatment. The critical threshold of N min supply level in the root zone (0–30 cm) should be around 150 kg N ha −1 for sustainable production. April to May in the winter–spring season and September to October in the autumn–winter season are the critical periods for root zone N manipulation during crop growth. However, control of organic manure inputs is another key factor to further reduce surplus N in the future.

Influence of Nitrate Fertilizer on Macronutrient Contents of Celery Plants on Soil-Less Culture

ABSTRACT Two rates of nitrate (NO3) supply were used in production of celery plants (Apium graveolens L., cv. ‘Istar’) grown on perlite or coir substrates. A standard nitrogen dose (CN) was compared to a concentration that was 25% less (RN). Other nutrients were supplied at the same level for both treatments. Plants were harvested after 85 d of growth, divided into leaves, petioles, internal stalks, basal disc, and roots, and the macronutrient contents [nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and sulfur (S)] were analyzed. The ratios between elements (Na/K, Mg/Ca, and N/P) were also determined at the whole plant level. Commercial yield was statistically the same for CN and RN treatments. Nutrient content for plants cultivated on coir were slightly higher than those on perlite. Petioles and leaves showed the highest accumulation of K, Ca, and Mg; the roots also had similar high levels. The basal disc and internal stalks tended to accumulate S. Nitrogen and P were uniformly distributed throughout the plant. Roots showed the highest accumulation of Na. On a whole plant basis, the nutrient contents for CN and RN were almost the same, with only a slightly higher N concentration for CN. Within the edible fraction (petioles + internal stalks), the RN treatment resulted in a higher concentrations for all the nutrients except N, compared to CN. Thus, celery plants cultivated with a nitrogen dose 25% lower than that commonly used by producers had a balanced nutrient content and were safer for consumers.