Comparison of ammonia emissions related to nitrogen use efficiency of livestock production in Europe

The increasing global demand for food and the environmental effects of reactive nitrogen losses in the food production chain, increase the need for efficient use of nitrogen (N). Of N harvested in agricultural plant products, 80% is used to feed livestock. Because the largest atmospheric loss of reactive nitrogen from livestock production systems is ammonia (NH₃), the focus of this paper is on N lost as NH₃ during the production of animal protein. The focus of this paper is to understand the key factors explaining differences in Nitrogen Use Efficiency (NUE) of animal production among various European countries. Therefore we developed a conceptual framework to describe the NUE defined as the amount of animal-protein N per N in feed and NH₃-N losses in the production of milk, beef, pork, chicken meat and eggs in The Netherlands, Switzerland, United Kingdom, Germany, Austria and Denmark. The framework describes how manure management and animal-related parameters (feed, metabolism) relate to NH₃ emissions and NUE. The results showed that the animal product with the lowest NUE had the largest NH₃ emissions and vice versa, which agrees with the reciprocal relationship between NUE and NH₃ within the conceptual framework. Across animal products for the countries considered, about 20% of the N in feed is lost as NH₃. The significant smallest proportion (12%) of NH₃-N per unit of Nfeed is from chicken production. The proportions for other products are 17%, 19%, 20% and 22% for milk, pork, eggs and beef respectively. These differences were not significantly different due to the differences among countries. For all countries, NUE was lowest for beef and highest for chicken. The production of 1 kg N in beef required about 5 kg N in feed, of which 1 kg N was lost as NH₃-N. For the production of 1 kg N in chicken meat, 2 kg N in feed was required and 0.2 kg was lost as NH₃. The production of 1 kg N in milk required 4 kg N in feed with 0.6 kg NH₃-N loss, the same as pork and eggs, but those needed 3 and 3.5 kg N in feed per kg N in product respectively. Except for beef, the differences among these European countries were mainly caused by differences in manure management practices and their emission factors, rather than by animal-related factors including feed and digestibility influencing the excreted amount of ammoniacal N (TAN). For beef, both aspects caused important differences. Based on the results, we encourage the expression of N losses as per N in feed or per N in product, in addition to per animal place, when comparing production efficiency and NUE. We consider that disaggregating emission factors into a diet/animal effect and a manure management effect would improve the basis for comparing national NH₃ emission inventories.

Monitoring of plasma levels of activated protein C using a clinically applicable oligonucleotide-based enzyme capture assay

BACKGROUND

Human-activated protein C (APC) is a serine protease with anticoagulant, anti-inflammatory and cytoprotective functions. This feature renders APC to be a promising vascular-inflammatory biomarker.

OBJECTIVE

The aim of the present study was the development and validation of a technique that allows the measurement of APC plasma levels under practical laboratory conditions.

METHODS/PATIENTS

Based on the APC-binding ssDNA aptamer HS02-52G we developed an oligonucleotide-based enzyme capture assay (OECA) that quantifies aptamer-captured APC through hydrolysis rates of a fluorogenic peptide substrate. After optimization of pre-analytical conditions, plasma APC levels were measured in healthy individuals and patients undergoing hip replacement surgery.

RESULTS AND CONCLUSION

A combination of APC-OECA with an aprotinin-based quenching strategy allowed APC analysis with a limit of detection as low as 0.022 ± 0.005 ng mL(-1) (0.39 ± 0.10 pmol L(-1)) and a limit of quantification of 0.116 ± 0.055 ng mL(-1) (2.06 ± 0.98 pmol L(-1)). While APC plasma levels in healthy individuals fell below the quantifiable range of the APC-OECA platform, levels substantially increased in patients undergoing hip replacement surgery reaching peak values of up to 12 ng mL(-1) (214 pmol L(-1)). When normalized to the amount of thrombin generated, interindividual variabilities in the APC generating capacity were observed. In general, with a turn-around time from blood sampling to generation of test results of < 7 h, the APC-OECA platform allows sensitive and rapid determination of circulating APC levels under pathological conditions.

Biocides used in building materials and their leaching behavior to sewer systems

There is increasing concern about diffuse pollution of aquatic systems by biocides used in urban areas. We investigated sources and pathways of biocides significant for the pollution of storm water runoff. Main sources seem to be building envelopes, i.e. facades (paints, plasters) and roof sealing membranes. First results from a defined urban catchment drained by a separated sewer system without any agricultural activities reveal a substantial occurrence. Even after the first flush, concentrations of terbutryn, carbendazim, mecoprop as well as Irgarol 1051 and its metabolite exceeded the Swiss water quality standard of 0.1 microg/L. In laboratory experiments, leaching of mecoprop used as a root protection agent in bitumen sheets for roof waterproofing was determined. The concentrations differed in 16 different sheets two orders of magnitude, depending on the product composition. Using optimized products, it is expected to be the most efficient and sustainable way to reduce the environmental impact. To understand transport dynamics and environmental risk, further storm water events will be analyzed. Based on the ongoing project URBIC, first measures will be proposed to limit the release to surface and ground water.

Fate and removal of polycyclic musks, UV filters and biocides during wastewater treatment

The fate of polycyclic musks (PCMs) (HHCB, AHTN, ADBI, AHDI, ATII, DPMI), UV filters (3-(4-methylbenzylidene) camphor, 4-MBC; octyl-methoxycinnamate, OMC; octocrylene, OC; octyl-triazone, OT) and biocides (permethrin, carbendazim) during wastewater treatment was studied on a full-scale plant. Average influent concentrations of OMC, HHCB, OC, AHTN, 4-MBC and OT were at 20070, 4420, 1680, 1430, 960 and 720 ng L(-1), respectively. The other PCMs, permethrin and carbendazim ranged between < limits of quantification and 670 ng L(-1). Concentrations in the water line decreased significantly for most compounds. Removal rates for PCMs ranged from 72% to 86%, for UV filters from 92% to >99% and were at 92% and 37% for permethrin and carbendazim, respectively. Removal during wastewater treatment was mainly driven by sorption onto solids and biodegradation. For anaerobic sludge digestion, elimination of PCMs, OMC and the biocides was observed.

Considerations about the enantioselective transformation of polycyclic musks in wastewater, treated wastewater and sewage sludge and analysis of their fate in a sequencing batch reactor plant

The present work consists of two distinct parts: in the first part enantioselective GC was used to separate the different enantiomeric/diastereomeric polycyclic musks, PCMs (HHCB, AHTN, AHDI, ATII and DPMI) including the main transformation product of HHCB, HHCB-lactone, in wastewater and sewage sludge. After optimization all PCMs were resolved on a cyclodextrin containing Rt-BDEXcst capillary GC column. Enantiomeric ratios of PCMs in a technical mixture were determined and compared to those obtained from enantioselective separation of wastewater and sewage sludge samples. In general, enantiomeric ratios were similar for most materials in influent, effluent and stabilized sewage sludge. However, the ratios for HHCB, AHDI and particularly ATII suggest some stereospecific removal of these compounds. In the second part, a field study was conducted on a wastewater treatment plant comprising a sequencing batch reactor. Concentrations of HHCB, AHTN, ADBI, AHDI, ATII, DPMI and HHCB-lactone were determined by non-enantioselective GC in daily samples of influent, effluent and activated sludge during one week. Mean concentrations in influent were 6900 and 1520 ng/l for HHCB and AHTN, respectively. The other PCMs exhibited contents 200 ng/l. Mean percent removal was between 61% (AHDI) and 87% (HHCB) resulting in mean effluent concentrations below 860 ng/l. HHCB-lactone concentration increased during wastewater treatment with a mean in the influent of 430 ng/l and in the effluent of 900 ng/l, respectively, indicating a degradation of HHCB.

Concentrations and specific loads of polycyclic musks in sewage sludge originating from a monitoring network in Switzerland

Polycyclic musks (HHCB, AHTN, ADBI, AHDI, ATII) and a metabolite of HHCB (HHCB-lactone) were analyzed in sewage sludge samples within the framework of a monitoring network in Switzerland. Mean values in stabilised sludge from 16 wastewater treatment plants were 20.3 mg/kg d.m. for HHCB, 7.3 mg/kg d.m. for AHTN and 1.8 mg/kg d.m. for HHCB-lactone, respectively. Contents of ADBI, AHDI and ATII were between 0.1 and 1.8 g/kg d.m. The results show that polycyclic musks origin mainly from private households and that loads from craft industry, industry and atmospheric deposition are negligible. The technology of wastewater treatment and sludge processing seems to be of minor importance for degradation processes of polycyclic musks. The calculated input in wastewater of polycyclic musks is lower by a factor of 5-7 than the estimates based on use volumes. This discrepancy might be explained by degradation processes, other emission pathways than wastewater or inappropriate estimation of production volumes.

Mechanical deformation promotes secretion of IL-1 alpha and IL-1 receptor antagonist

Both IL-1 alpha and IL-1 beta lack an N terminus secretory sequence, and the mechanism of secretion of these pleiotropic cytokines is incompletely understood. The epidermis contains large quantities of IL-1 alpha in keratinocytes, which may play a role in inducing endothelial adhesion molecules and promoting extravasation of leukocytes. Here we report that mechanical deformation of human keratinocytes leads to rapid release of IL-1 alpha, possibly through transient disruptions in the plasma membrane. Using a device that precisely controls the amplitude of strain on the culture substrate, we found by pulse-chase analysis, Western analysis, and ELISA that the release of IL-1 alpha is dependent on the amplitude of the strain. A cyclic strain of 14% released a small but significant quantity of IL-1 alpha, while strains of 33% released 66 +/- 9% of cytoplasmic IL-1 alpha over 1 h (p < 0.001). Release of IL-1 alpha was accompanied by rapid release of large stores of IL-1R antagonist, approximately 25 to 30 times greater by mass than the quantity of IL-1 alpha released, but only a small fraction of cytoplasmic lactate dehydrogenase. Media conditioned by mechanically stimulated keratinocytes induced expression of E-selectin by human vascular endothelial cells; induction of E-selectin was completely inhibited by an Ab to IL-1 alpha. Therefore, mechanical strain promotes the secretion of IL-1 alpha, and deformation of keratinocytes in the epidermis may activate vascular endothelium through mechanically released IL-1 alpha. This pathophysiologic mechanism may play a role in the anatomic localization of some inflammatory skin diseases, such as psoriasis, which occurs more commonly in locations where the dermis is subjected to repetitive stretch or trauma.

Mechanical deformation promotes secretion of IL-1 alpha and IL-1 receptor antagonist

Both IL-1 alpha and IL-1 beta lack an N terminus secretory sequence, and the mechanism of secretion of these pleiotropic cytokines is incompletely understood. The epidermis contains large quantities of IL-1 alpha in keratinocytes, which may play a role in inducing endothelial adhesion molecules and promoting extravasation of leukocytes. Here we report that mechanical deformation of human keratinocytes leads to rapid release of IL-1 alpha, possibly through transient disruptions in the plasma membrane. Using a device that precisely controls the amplitude of strain on the culture substrate, we found by pulse-chase analysis, Western analysis, and ELISA that the release of IL-1 alpha is dependent on the amplitude of the strain. A cyclic strain of 14% released a small but significant quantity of IL-1 alpha, while strains of 33% released 66 +/- 9% of cytoplasmic IL-1 alpha over 1 h (p &lt; 0.001). Release of IL-1 alpha was accompanied by rapid release of large stores of IL-1R antagonist, approximately 25 to 30 times greater by mass than the quantity of IL-1 alpha released, but only a small fraction of cytoplasmic lactate dehydrogenase. Media conditioned by mechanically stimulated keratinocytes induced expression of E-selectin by human vascular endothelial cells; induction of E-selectin was completely inhibited by an Ab to IL-1 alpha. Therefore, mechanical strain promotes the secretion of IL-1 alpha, and deformation of keratinocytes in the epidermis may activate vascular endothelium through mechanically released IL-1 alpha. This pathophysiologic mechanism may play a role in the anatomic localization of some inflammatory skin diseases, such as psoriasis, which occurs more commonly in locations where the dermis is subjected to repetitive stretch or trauma.

Interleukin 6: insights to its function in skin by overexpression in transgenic mice

Interleukin 6 (IL-6) is a cytokine that mediates a wide range of inflammatory and immune responses. Its expression is elevated in inflammatory or immunodeficient diseases, including psoriasis, rheumatoid arthritis, and AIDS. To explore the role of IL-6 in skin, we utilized a human keratin 14 (K14) promoter to express IL-6 in the basal cells of stratified squamous epithelia of transgenic mice. Mice expressing the K14-IL-6 transgene were smaller than normal and exhibited retarded hair growth. Surprisingly, IL-6 expression did not lead to enhanced epidermal proliferation, but it did result in a thicker stratum corneum, with an otherwise seemingly normal program of differentiation. IL-6 expression did not lead to leukocytic infiltration, making it unlikely that it has direct proinflammatory activity in skin. Based on this study, one role of IL-6 relevant to host defense may be to enhance the stratum corneum, thereby providing increased protection from injurious stimuli or infection. If IL-6 plays additional roles in the skin, it is likely to act synergistically with factors that IL-6 alone cannot induce.

Interactions between ultraviolet light and interleukin-1 on MSH binding in both mouse melanoma and human squamous carcinoma cells

Interactions between beta-melanotropin (MSH), interleukin 1-a (IL-1), and ultraviolet light (UV) were examined in Cloudman S91 mouse melanoma and RHEK human squamous carcinoma cell lines. The following points were established: 1) both cell lines produced IL-1 and their production was stimulated by exposure of the cells to UV; 2) both cell lines possessed high affinity binding sites for MSH, and their ability to bind MSH was modulated by IL-1; 3) IL-1 exhibited both stimulatory and inhibitory effects on MSH binding to Cloudman cells; and 4) the stimulatory effect of IL-1 on MSH binding to melanoma cells was reflected in enhanced cellular responsiveness to MSH regarding tyrosinase activity (E.C. 1.14.18.1) and melanin content. The findings raise the possibility that interactions between keratinocytes and melanocytes may be regulated by IL-1 and MSH, and suggest a possible mechanism for stimulation of cutaneous melanogenesis by solar radiation: enhancement of MSH receptor activity by induction of IL-1.

Interleukin-1 alpha mRNA induced by cycloheximide PMA, and retinoic acid is reduced by dexamethasone in PAM-212 keratinocytes

Keratinocytes in culture produce detectable amounts of IL-1 alpha mRNA constitutively and can be stimulated to express increased amounts of IL-1 alpha mRNA by cycloheximide, PMA, and retinoic acid. Dexamethasone decreases the amount of IL-1 mRNA induced by these agents, as well as constitutive IL-1 alpha mRNA. RU 486, which interferes with glucocorticosteroid-receptor binding, decreases inhibition of TPA stimulation of IL-1 alpha mRNA by dexamethasone, which suggests that the inhibition by dexamethasone is through a conventional ligand-receptor mechanism.

Growth of an interleukin 2/interleukin 4-dependent T cell line induced by granulocyte-macrophage colony-stimulating factor (GM-CSF)

Lymphokine activities in conditioned medium from activated helper T cell lines are most commonly defined by the proliferation of "specific" lymphokine-dependent cell lines. Various sublines of IL 2-dependent (and ostensibly specific) HT-2 and CTLL cells have now been shown to proliferate in response to BSF-1/IL 4 as well. After activation with antigen or mitogen, D10.G4.1, an antigen-specific cloned T helper cell that has recently been shown to produce IL 4 but not IL 2, secretes two distinct cytokines that induce the growth of HT-2 cells. These "T cell growth factors" (TCGF) can be separated by reversed phase high-performance liquid chromatography (RP-HPLC). The TCGF activity of one of these factors can be blocked by 11B11, an antibody specific for IL 4. The second TCGF activity is not affected by 11B11 or by antibodies specific for IL 2. This TCGF activity can be neutralized by a goat polyclonal antibody to granulocyte-macrophage colony-stimulating factor (GM-CSF), and has a RP-HPLC elution profile identical to that of recombinant GM-CSF. Recombinant GM-CSF induces both proliferation and long-term growth of HT-2 but not CTLL cells, and this activity can be neutralized by the same antibody to GM-CSF. GM-CSF is best known as a factor that induces the maturation and growth of granulocytes and macrophages from bone marrow-derived hematopoietic precursor cells. The ability of GM-CSF to induce the growth of certain T cell lines indicates that this molecule may play a role in T cell-mediated immune responses, either as an autocrine growth factor or a paracrine stimulus from both lymphoid and nonlymphoid tissues that produce this cytokine.

Autocrine growth of T cells independent of interleukin 2: identification of interleukin 4 (IL 4, BSF-1) as an autocrine growth factor for a cloned antigen-specific helper T cell

Interleukin 4 (IL 4), formerly known as B cell stimulatory factor 1 (BSF-1), has recently been described as a growth factor for T cells. The role of IL 4 in the putatively IL 2-independent growth of certain cloned T helper cells is unclear. D10.G4.1 (D10) is a conalbumin-specific helper T cell that has been employed extensively in the analysis of T cell activation and as an assay for the detection of IL 1. Previously, it was thought that IL 1 induced the expression of IL 2 receptors on D10 cells, thereby permitting D10 to proliferate in response to endogenously produced IL 2. However, we cannot detect IL 2 mRNA or protein in D10 cells or their supernatants as determined by the following criteria: monoclonal antibodies that neutralize the in vitro activity of murine IL 2 do not block the IL 1-dependent proliferation of D10 cells; no competitive binding for high-affinity IL 2 receptors with 125I-labeled IL 2 can be detected with medium conditioned by activated D10 cells; and Northern blot analysis and S1 nuclease protection assays, performed with cDNA probes for IL 2, do not detect mRNA for IL 2 under a variety of different activation conditions that foster autocrine growth of D10 cells. In contrast, activated D10 cells produce both IL 4 mRNA and protein as judged by similar criteria. Purified IL 4 has significant TCGF activity as measured by proliferation of HT-2 cells. This activity can be blocked completely by a monoclonal antibody to IL 4 (11B11). The proliferation of D10 cells in the presence of 3D3 (a clonotype-specific monoclonal anti-T cell receptor antibody) and IL 1 can be blocked completely by 11B11 antibody. Highly purified IL 4 alone cannot induce the proliferation of resting D10 cells; however, equivalent amounts of IL 4 in the presence of recombinant IL 1 induce significant D10 proliferation. Therefore, IL 1 appears to render D10 cells responsive to their autocrine growth signal. These data indicate that IL 4 serves as the autocrine T cell growth factor for D10 cells, and that exogenous IL 1 is required for the transduction of this growth signal. This may represent a more broadly applicable mechanism for the growth of certain subsets of T helper cells.

Autocrine growth of T cells independent of interleukin 2: identification of interleukin 4 (IL 4, BSF-1) as an autocrine growth factor for a cloned antigen-specific helper T cell

Interleukin 4 (IL 4), formerly known as B cell stimulatory factor 1 (BSF-1), has recently been described as a growth factor for T cells. The role of IL 4 in the putatively IL 2-independent growth of certain cloned T helper cells is unclear. D10.G4.1 (D10) is a conalbumin-specific helper T cell that has been employed extensively in the analysis of T cell activation and as an assay for the detection of IL 1. Previously, it was thought that IL 1 induced the expression of IL 2 receptors on D10 cells, thereby permitting D10 to proliferate in response to endogenously produced IL 2. However, we cannot detect IL 2 mRNA or protein in D10 cells or their supernatants as determined by the following criteria: monoclonal antibodies that neutralize the in vitro activity of murine IL 2 do not block the IL 1-dependent proliferation of D10 cells; no competitive binding for high-affinity IL 2 receptors with 125I-labeled IL 2 can be detected with medium conditioned by activated D10 cells; and Northern blot analysis and S1 nuclease protection assays, performed with cDNA probes for IL 2, do not detect mRNA for IL 2 under a variety of different activation conditions that foster autocrine growth of D10 cells. In contrast, activated D10 cells produce both IL 4 mRNA and protein as judged by similar criteria. Purified IL 4 has significant TCGF activity as measured by proliferation of HT-2 cells. This activity can be blocked completely by a monoclonal antibody to IL 4 (11B11). The proliferation of D10 cells in the presence of 3D3 (a clonotype-specific monoclonal anti-T cell receptor antibody) and IL 1 can be blocked completely by 11B11 antibody. Highly purified IL 4 alone cannot induce the proliferation of resting D10 cells; however, equivalent amounts of IL 4 in the presence of recombinant IL 1 induce significant D10 proliferation. Therefore, IL 1 appears to render D10 cells responsive to their autocrine growth signal. These data indicate that IL 4 serves as the autocrine T cell growth factor for D10 cells, and that exogenous IL 1 is required for the transduction of this growth signal. This may represent a more broadly applicable mechanism for the growth of certain subsets of T helper cells.

Growth of an interleukin 2/interleukin 4-dependent T cell line induced by granulocyte-macrophage colony-stimulating factor (GM-CSF)

Lymphokine activities in conditioned medium from activated helper T cell lines are most commonly defined by the proliferation of "specific" lymphokine-dependent cell lines. Various sublines of IL 2-dependent (and ostensibly specific) HT-2 and CTLL cells have now been shown to proliferate in response to BSF-1/IL 4 as well. After activation with antigen or mitogen, D10.G4.1, an antigen-specific cloned T helper cell that has recently been shown to produce IL 4 but not IL 2, secretes two distinct cytokines that induce the growth of HT-2 cells. These "T cell growth factors" (TCGF) can be separated by reversed phase high-performance liquid chromatography (RP-HPLC). The TCGF activity of one of these factors can be blocked by 11B11, an antibody specific for IL 4. The second TCGF activity is not affected by 11B11 or by antibodies specific for IL 2. This TCGF activity can be neutralized by a goat polyclonal antibody to granulocyte-macrophage colony-stimulating factor (GM-CSF), and has a RP-HPLC elution profile identical to that of recombinant GM-CSF. Recombinant GM-CSF induces both proliferation and long-term growth of HT-2 but not CTLL cells, and this activity can be neutralized by the same antibody to GM-CSF. GM-CSF is best known as a factor that induces the maturation and growth of granulocytes and macrophages from bone marrow-derived hematopoietic precursor cells. The ability of GM-CSF to induce the growth of certain T cell lines indicates that this molecule may play a role in T cell-mediated immune responses, either as an autocrine growth factor or a paracrine stimulus from both lymphoid and nonlymphoid tissues that produce this cytokine.