Factors determining the leaching of nitrogen from soil,including some aspects of maintenance of water quality     

J. Jung 《Plant foods for human nutrition (Dordrecht, Netherlands)》1972,21(4):343-366

N leaching from the topsoil, which occurs both by vertical percolation and runoff, is becoming increasingly important, not only from the point of view of crop production but also in the maintenance of water quality. N runoff from sloping fields has not yet been investigated extensively, but lysimeter studies have provided us with comprehensive data on vertical percolation of this nutrient. Numerous investigations throughout Europe have determined the most important factors concerned with N leaching from the topsoil and their relationship to water quality. The results may be summarized as follows: The amount and distribution of rainfall have a considerable effect on translocation of N from the topsoil. To exactly what extent is determined by the amount of water leached, which in turn depends to a large degree on the growth of the plant. Therefore the vegetative cover, as a result of its water utilization (mainly by transpiration) and its nutrient uptake, is often the most important factor in N leaching. This is borne out by the fact that by far the greatest leaching occurs in uncropped land (fallow) and during the part of the year where little growth occurs. Under crops with a limited root system and low transpiration, such as vines, leaching will also be higher than under a profuse plant cover (e.g. grassland). The main effect of the soil itself depends on its own N reserves and their mineralization rate. The amount of naturally occurring N in a mineral soil can vary between 600 and 12,000 kg/ha. Of this, approximately 10 – 250 kg/ha is given off anually under European climatic conditions. Thus as well as the factors already mentioned, the soil's N reserves also play an important part in the extent of N leaching. The vast majority of lysimeter studies carried out in Europe prove that the addition of N in mineral fertilizers has comparatively little influence on the amount of N leached out. An important point about N fertilizers is that they are applied when needed by the plant, which of course cannot occur in nature with the N from mineralization of the soil reserves. According to the data on hand, less than 5% of the N added in the form of mineral fertilizers will be leached out. Although excessive rates of N in lysimeter trials led to increased translocation into the subsoil, it was also proved that as a result of increased plant growth, N leaching losses were lower in a plot fertilized with N than in the PK control. Since N is leached out almost exclusively in the form of nitrate, and since the ammonium added as fertilizer is converted relatively quickly to nitrate, there is little difference in the leaching losses following application of the various types of N used today. The time of application, however, can be a determining factor. Gaseous N losses, in particular as a result of denitrification, can also affect N leaching indirectly. Discussion of N leaching leads inevitably to the question of water quality maintenance and what part N leached from soil plays in the eutrophication of surface waters and the nitrate content of ground water. The effect of agricultural land on the nitrate content of ground water depends on the cropping system: Vines, for instance, do not have a very extensive root system, and there are high leaching losses from the soil of vineyards. Under permanent grassland, on the other hand, the lowest losses have been recorded. In crops with a limited root system it is theoretically impossible to avoid an increase in the nitrate level of the ground water following high N application rates. This is however only a theory, and has not yet been fully investigated. In relation to agriculture as a whole these cases are to be regarded as exceptions, and they could possibly be improved by new agricultural techniques. As far as eutrophication is concerned, N leaching and the factors that affect it are of minor importance, since nitrogen, in contrast to phosphate, is already present in surface water at a concentration high enough to cause eutrophication. To sum up, it may be said that high rates of N are applied in intensive agriculture, but they do not usually lead to an increased N content in ground water and surface water. The reason for this is that the additional N promotes plant growth, which results in a greater nutrient uptake, and rationalization of agricultural methods on economic grounds ensures an adequate utilization of nutrients by applying rates commensurate with and timed according to the crop's need.  相似文献   

Systemic Concentrations of Endogenous and Exogenous FSH in Anoestrous Ewes Superstimulated with Folltropin^®-V     

PM Bartlewski  KJ Fuerst  BD Alexander  WA King 《Reproduction in domestic animals》2009,44(2):353-358

The synchronization of follicular waves with medroxyprogesterone acetate (MAP) and oestradiol‐17β (E₂‐17β) prior to ovarian superstimilation in anoestrous ewes reduces the variability in superovulatory responses by an unknown mechanism. Follicle stimulating hormone (FSH) is a primary promoter of antral follicular development, but the relevance of circulating FSH concentrations to the superovulation performance in ewes has not been examined. Eighteen anoestrous Rideau Arcott ewes (May–June) were superovulated with Folltropin^®‐V (porcine FSH), with (n = 8; treated ewes) or without (n = 10; control ewes) a single i.m. dose of 350 μg of E₂‐17β, given on the sixth day of a 14‐day treatment with MAP‐releasing intravaginal sponges (60 mg). The superovulatory treatment, begun 6 days after E₂‐17β injection, consisted of six i.m. applications of Folltropin^®‐V given twice daily (at 08:00 and 16:00 h), followed by an i.m. injection of GnRH (50 μg). Blood samples collected every 8 h throughout the 3‐day treatment, were analysed by radioimmunoassays for concentrations of ovine and porcine FSH, using species‐specific standards and primary antibodies. Serum concentrations of oFSH were greater (p < 0.05) in the controls compared to treated ewes at 40, 64 and 72 h and the variability in mean oFSH concentrations was greater (p < 0.05) in control ewes at 40, 48, 64 and 72 h after the 1^st Folltropin^®‐V injection. There were no differences (p > 0.05) between the two groups in serum concentrations of pFSH. Significant correlations were recorded between the number of corpora lutea (CL) and oFSH concentrations at 8 h (r = 0.72, p < 0.05), 16 h (r=0.63, p < 0.05) and 64 h (r = 0.84, p < 0.01) after the 1^st Folltropin^®‐V injection. The total number of recovered embryos was positively correlated to oFSH concentrations at 56 h (r = 0.69, p < 0.05). We concluded that changes in endogenous FSH concentrations during ovarian superstimulation with pFSH might contribute to the variability in superovulatory responses in ewes.  相似文献   

Synergistic effect of ERK inhibition on tetrandrine-induced apoptosis in A549 human lung carcinoma cells     

Hyun Sun Cho  Seung Hee Chang  Youn Sun Chung  Ji Young Shin  Sung Jin Park  Eun Sun Lee  Soon Kyung Hwang  Jung Taek Kwon  Arash Minai Tehrani  Minah Woo  Mi Sook Noh  Huda Hanifah  Hua Jin  Cheng Xiong Xu  Myung Haing Cho 《Journal of veterinary science (Suw?n-si, Korea)》2009,10(1):23-28

Tetrandrine (TET), a bis-benzylisoquinoline alkaloid from the root of Stephania tetrandra, is known to have anti-tumor activity in various malignant neoplasms. However, the precise mechanism by which TET inhibits tumor cell growth remains to be elucidated. The present studies were performed to characterize the potential effects of TET on phosphoinositide 3-kinase/Akt and extracellular signal-regulated kinase (ERK) pathways since these signaling pathways are known to be responsible for cell growth and survival. TET suppressed cell proliferation and induced apoptosis in A549 human lung carcinoma cells. TET treatment resulted in a down-regulation of Akt and ERK phosphorylation in both time-/concentration-dependent manners. The inhibition of ERK using PD98059 synergistically enhanced the TET-induced apoptosis of A549 cells whereas the inhibition of Akt using {"type":"entrez-nucleotide","attrs":{"text":"LY294002","term_id":"1257998346","term_text":"LY294002"}}LY294002 had a less significant effect. Taken together, our results suggest that TET: i) selectively inhibits the proliferation of lung cancer cells by blocking Akt activation and ii) increases apoptosis by inhibiting ERK. The treatment of lung cancers with TET may enhance the efficacy of chemotherapy and radiotherapy and increase the apoptotic potential of lung cancer cells.  相似文献   

A novel ��-glucan produced by Paenibacillus polymyxa JB115 induces nitric oxide production in RAW264.7 macrophages     

Zhi-Qiang Chang  Joong-Su Lee  Mi-Hyun Hwang  Joo-Heon Hong  Hee-Kyoung Jung  Sam-Pin Lee  Seung-Chun Park 《Journal of veterinary science (Suw?n-si, Korea)》2009,10(2):165-167

The effect of extracellular β-(1→3), (1→6)-glucan, produced by Paenibacillus polymyxa JB115, on nitric oxide (NO) production in RAW264.7 macrophages was investigated. β-glucan induced the production of NO by RAW264.7 macrophages in a concentration- and time-dependent manner. Moreover, β-glucan stimulation increased the mRNA expression of iNOS, COX-2 and IL-6 in RAW264.7 macrophages in a concentration-dependent manner.  相似文献   

Imaging evaluation of the liver using multi-detector row computed tomography in micropigs as potential living liver donors     

Jung Min Ryu  Dong Hyun Kim  Min Young Lee  Sang Hun Lee  Jae Hong Park  Seung Pil Yun  Min Woo Jang  Seong Hwan Kim  Gyu Jin Rho  Ho Jae Han 《Journal of veterinary science (Suw?n-si, Korea)》2009,10(2):93-98

The shortage of organ donors has stimulated interest in the possibility of using animal organs for transplantation into humans. In addition, pigs are now considered to be the most likely source animals for human xenotransplantation because of their advantages over non-human primates. However, the appropriate standard values for estimations of the liver of micropigs have not been established. The determination of standard values for the micropig liver using multi-detector row computed tomography (MDCT) would help to select a suitable donor for an individual patient, determine the condition of the liver of the micropigs and help predict patient prognosis. Therefore, we determined the standard values for the livers of micropigs using MDCT. The liver parenchyma showed homogenous enhancement and had no space-occupying lesions. The total and right lobe volumes of the liver were 698.57 ± 47.81 ml and 420.14 ± 26.70 ml, which are 51.74% and 49.35% of the human liver volume, respectively. In micropigs, the percentage of liver volume to body weight was approximately 2.05%. The diameters of the common hepatic artery and proper hepatic artery were 6.24 ± 0.20 mm and 4.68 ± 0.13 mm, respectively. The hepatic vascular system of the micropigs was similar to that of humans, except for the variation in the length of the proper hepatic artery. In addition, the diameter of the portal vein was 11.27 ± 0.38 mm. In conclusion, imaging evaluation using the MDCT was a reliable method for liver evaluation and its vascular anatomy for xenotransplantation using micropigs.  相似文献   

The effect of Eucommia ulmoides leaf supplementation on the growth performance, blood and meat quality parameters in growing and finishing pigs     

Sung Dae LEE  †  Hoi Yun KIM  †  Young Min SONG  Hyun Jung JUNG  Sang Yun JI  Hae Dong JANG  Jae Weon RYU  June Cheol PARK  Hong Kil MOON  In Cheul KIM 《Animal Science Journal》2009,80(1):41-45

The aim of the present study was to investigate the effect of Eucommia ulmoides leaf (EUL) supplementation on the growth performance, blood and meat quality parameters in growing and finishing pigs. Ninety gilts (L × LW × D, 20 kg initialBW) were housed 10 per pen in a front‐open building with three replicate pens per treatment. Experimental treatment was started from the beginning of the growing stage (20 ± 3 kg) by supplementing EUL at 0(C), 3(T1) and 5% (T2) to the growing and finishing diet. Pigs were slaughtered by electrical stunning at 105 ± 3 kg live weight. Average daily feed intake (ADFI, kg/day) decreased (P < 0.05) by addition of EUL in growth performance, average daily gain (ADG, kg/day) was lower (P < 0.05) in T1 and T2 than in C. In hematology, leukocytes (WBC, 10³/mm³) decreased (P < 0.05) in T1 and T2 than in C. Erythrocytes (RBC, 10⁶/mm³), hemoglobin (HGB, g/dL) and hematocrit (HCT, %) increased (P < 0.05) in T1 and T2 than in C. Platelet (PLT, 10³/mm³) was lower (P < 0.05) in T2 than in C and T1. In biochemical composition of serum, total protein (g/dL), r‐GTP (μ/L), total cholesterol (mg/dL) and triglycerides (mg/dL) were lower (P < 0.05) in T1 and T2 than in C. On longissimus dorsi muscle, crude protein was higher (P < 0.05) in T1 than in C. Crude ash was higher (P < 0.05) in T1 and T2 than in C. Yellow to blue color scale (CIE b*) in meat color was higher (P < 0.05) in T2 than in C. CIE b* in back fat color was higher (P < 0.05) in T2 than in the other treatments. In sensory evaluation scores for fresh meat, the values of meat color, fat color, drip loss and marbling were not significantly affected by addition of EUL. In cooked meat, the values of chewiness and overall acceptability were higher (P < 0.05) in T1 and T2 than in C. The results indicate that the addition of EUL affected growth performance, blood parameters and meat quality parameters in growing and finishing pigs.  相似文献   

Ameliorative effects of proanthocyanidin on oxidative stress and inflammation in streptozotocin-induced diabetic rats     

Lee YA  Kim YJ  Cho EJ  Yokozawa T 《Journal of agricultural and food chemistry》2007,55(23):9395-9400

Recent evidence strongly suggests that oxidative stress due to redox imbalance is causally associated with inflammatory processes and various diseases including diabetes. We examined the effects of proanthocyanidin from persimmon peel, using both oligomers and polymers, against oxidative stress with elucidation of the underlying mechanisms in streptozotocin-induced diabetic rats. The elevation of lipid peroxidation in the kidney and serum under the diabetic condition was decreased by the administration of proanthocyanidin. The suppression of reactive oxygen species generation and elevation of the reduced glutathione/oxidized glutathione ratio were observed in the groups administered proanthocyanidin. These results support the protective role of proanthocyanidin from oxidative stress induced by diabetes. Moreover, proanthocyanidin, especially its oligomeric form, affected the inflammatory process with regulation of related protein expression, inducible nitric oxide synthase, cyclooxygenase-2, and upstream regulators, nuclear factor kappaB, and inhibitor-binding protein kappaB-alpha. Proanthocyanidin ameliorated the diabetic condition by decreases of serum glucose, glycosylated protein, serum urea nitrogen, urinary protein, and renal advanced glycation endproducts. In particular, oligomeric proanthocyanidin exerted a stronger protective activity than the polymeric form. This suggests that the polymerization of proanthocyanidin has an effect on its protective effect against diabetes. The present study supports the beneficial effect of proanthocyanidin against diabetes and oxidative stress-related inflammatory processes.  相似文献   

Purification and characterization of an antifungal protein, C-FKBP, from Chinese cabbage     

Park SC  Lee JR  Shin SO  Jung JH  Lee YM  Son H  Park Y  Lee SY  Hahm KS 《Journal of agricultural and food chemistry》2007,55(13):5277-5281

An antifungal protein was isolated from Chinese cabbage (Brassica campestris L. ssp. pekinensis) by buffer-soluble extraction and two chromatographic procedures. The results of matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry revealed that the isolated Chinese cabbage protein was identical to human FK506-binding protein (FKBP). A cDNA encoding FKBP was isolated from a Chinese cabbage leaf cDNA library and named C-FKBP. The open reading frame of the gene encoded a 154-amino acid polypeptide. The amino acid sequence of C-FKBP exhibits striking degrees of identity with the corresponding mouse (61%), human (60%), and yeast (56%) proteins. Genomic Southern blot analyses using the full-length C-FKBP cDNA probe revealed a multigene family in the Chinese cabbage genome. The C-FKBP mRNA was highly expressed in vegetative tissues. We also analyzed the antifungal and peptidyl-prolyl cis-trans isomerase activity of recombinant C-FKBP protein expressed in Escherichia coli. This protein inhibited pathogenic fungal strains, including Candida albicans, Botrytis cinerea, Rhizoctonia solani, and Trichoderma viride, whereas it exhibited no activity against E. coli and Staphylococcus aureus. These results suggest that recombinant C-FKBP is an excellent candidate as a lead compound for the development of antifungal agents.  相似文献   

Effects of Resistant Starch and Fiber from High‐Amylose Non‐Floury Corn on Tortilla Texture     

Kim A. Rohlfing  Alix Paez  Hyun Jung Kim  Pamela J. White 《Cereal Chemistry》2010,87(6):581-585

A high‐amylose, non‐floury corn, a floury corn, and a 1:1 blend were made into masa and then tortillas. The masa flour made with the high‐amylose corn had a greater amount of resistant starch (RS 28.8%) and a greater amount of total dietary fiber (TDF 42.1%) than that with the floury corn (RS 2.9%, TDF 9.6%), producing a high‐fiber tortilla. The masa was evaluated for pasting properties using a Rapid ViscoAnalyser (RVA). The high‐amylose masa slurry gelatinized little at 95°C. The floury masa had the greatest peak viscosity, whereas the 1:1 blend was intermediate in value. Sensory evaluations of the tortillas for the textural attributes showed the floury tortillas to be chewier, more rollable, and grittier than the high‐amylose tortillas, whereas the blend tortillas were intermediate for most attributes. The cutting force of the high‐amylose tortillas, measured on a texture analyzer, was very low; the blend and floury tortillas required more force. Chewiness was correlated to rollability (r = 0.99, P = 0.05). The %RS and %TDF were correlated to rollability (r = –0.99), and cutting force (r = 0.99). The floury and blend tortillas had firm textures expected of desirable tortillas, whereas the high‐amylose tortillas broke under little force, and would not roll. The high‐amylose tortillas had high amounts of RS and TDF but poor texture. The blend tortillas retained most floury tortilla textural properties, making them suitable products for consumer use.  相似文献   

Antigenic differences of the scuticociliate Miamiensis avidus from Japan     

J-Y Song  K Sasaki  T Okada  M Sakashita  H Kawakami  S Matsuoka  H-S Kang  K Nakayama  S-J Jung  M-J Oh  S-I Kitamura 《Journal of fish diseases》2009,32(12):1027-1034

In Japan and Korea, outbreaks of scuticociliatosis have frequently occurred in Japanese flounder, Paralichthys olivaceus . Morphological observations and small subunit rRNA gene sequences have shown that the causative agent of scuticociliatosis in the flounder is Miamiensis avidus (syn. Philasterides dicentrarchi ). In this study, we elucidated the antigenic differences between six Japanese M. avidus isolates as an initial step toward developing an effective vaccine against the disease. Four Japanese flounder isolates (IyoI, Nakajima, JF05To and Mie0301 isolates), one spotted knifejaw, Oplegnathus punctatus, isolate (SK05Kyo), and one ridged-eye flounder, Pleuronichthys cornutus , isolate (RF05To) were subjected to serological analysis. Antisera against IyoI, SK05Kyo, Nakajima and Mie0301 isolates were raised in rabbits and used for immobilization assays and Western blotting. Immobilization assays showed that the six isolates could be divided into three groups, tentatively designated serotype I for IyoI, JF05To, RF05To, SK05Kyo, serotype II for Nakajima and serotype III for Mie0301. Western blotting results supported these three serotypes, with marked similarities in the banding profiles of IyoI, JF05To, RF05To and SK05Kyo isolates, which were distinct from the Nakajima and Mie0301 isolates. Three isolates, IyoI, Nakajima and Mie0301 that were selected as representatives of each serotype, were highly pathogenic to Japanese flounder by experimental infection. Based on these findings, we propose that there are at least three M. avidus serotypes in Japan.  相似文献