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1.
J Environ Qual ; 47(1): 156-161, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29415100

ABSTRACT

Broiler litter contains 17ß-estradiol, estrone, and testosterone, which can contaminate surface waters when surface applied to grasslands and no-till fields. The objective of this study was to evaluate the effects of litter type (full or cake cleanout), litter treatment (none or sodium bisulfate), and number of flocks raised on the litter (1-5) on sex hormone concentrations. Our results showed that in untreated broiler litter, cake cleanout had greater concentrations of 17ß-estradiol, estrone, and testosterone than full cleanout, whereas in litter treated with sodium bisulfate, only the concentration of 17ß-estradiol was greater in cake than in full cleanout. The concentrations of 17ß-estradiol and estrone in untreated broiler litter increased as the number of flocks increased from one to three, with the largest increase observed for estrone in cake cleanout. We also sampled three broiler houses in brooding and nonbrooding sections during the growout period. We found no differences in hormone concentrations between sections of each house, but changes in hormone concentrations during growout varied depending on broiler litter water content. Water contents corresponding to ∼60% water-filled porosity favored a decrease in hormone concentrations with time, whereas a water-filled porosity of 44% was associated with increases in hormone concentration, probably due to slow decomposition rates. Our results suggest that cake cleanout of untreated litter, as well as all cleanouts from houses that have raised several flocks on the same bedding, may be good targets for treatments that can reduce hormone concentrations before the litter is surface applied to fields.


Subject(s)
Estradiol/analysis , Manure , Testosterone/analysis , Animals , Chickens
2.
J Environ Qual ; 47(1): 162-169, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29415101

ABSTRACT

Broiler () litter is subject to ammonia (NH) volatilization losses. Previous work has shown that the addition of gypsum to broiler litter can increase nitrogen mineralization and decrease NH losses due to a decrease in pH, but the mechanisms responsible for these effects are not well understood. Therefore, three laboratory studies were conducted to evaluate the effect of gypsum addition to broiler litter on (i) urease activity at three water contents, (ii) calcium carbonate precipitation, and (iii) pH. The addition of gypsum to broiler litter increased ammonium concentrations ( < 0.0033) and decreased litter pH by 0.43 to 0.49 pH units after 5 d ( < 0.0001); however, the rate of urea hydrolysis in treated litter only increased on Day 0 for broiler litter with low (0.29 g HO g) and high (0.69 g HO g) water contents, and on Day 3 for litter with medium (0.40 g HO g) water content ( < 0.05). Amending broiler litter with gypsum also caused an immediate decrease in litter pH (0.22 pH units) due to the precipitation of calcium carbonate (CaCO) from gypsum-derived calcium and litter bicarbonate. Furthermore, as urea was hydrolyzed, more urea-derived carbon precipitated as CaCO in gypsum-treated litter than in untreated litter ( < 0.001). These results indicate that amending broiler litter with gypsum favors the precipitation of CaCO, which buffers against increases in litter pH that are known to facilitate NH volatilization.


Subject(s)
Calcium Carbonate/chemistry , Calcium Sulfate/chemistry , Manure , Animals , Chickens , Hydrolysis , Urea
3.
Poult Sci ; 96(8): 2676-2683, 2017 Aug 01.
Article in English | MEDLINE | ID: mdl-28482091

ABSTRACT

A major concern of the broiler industry is the volatilization of ammonia (NH3) from the mixture of bedding material and broiler excretion that covers the floor of broiler houses. Gypsum has been proposed as a litter amendment to reduce NH3 volatilization, but reports of NH3 abatement vary among studies and the mechanism responsible for decreasing NH3 volatilization is not well understood. The goal of this study was to evaluate the effect of adding 20 or 40% flue-gas desulfurization gypsum (FGDG) to broiler litter on pH, electrical conductivity (EC), water potential, urea-degrading bacteria abundance, NH3 and carbon dioxide (CO2) evolution, and nitrogen (N) mineralization in several 21-d experiments. The addition of FGDG to broiler litter increased EC by 24 to 33% (P < 0.0001), decreased urea-degrading bacteria by 48 to 57% (P = 0.0001) and increased N mineralization by 10 to 11% (P = 0.0001) as compared to litters not amended with FGDG. Furthermore, the addition of FGDG to broiler litter decreased NH3 volatilization by 18 to 28% (P < 0.0001), potentially resulting from the significantly lower litter pH values compared to un-amended litter (P < 0.0001). Findings of this study indicate that amending broiler litter with 20% FGDG can decrease NH3 volatilization and increase the fertlizer value of broiler litter.


Subject(s)
Air Pollution/prevention & control , Ammonia/chemistry , Bacteria/metabolism , Calcium Sulfate/chemistry , Chickens , Floors and Floorcoverings , Manure/analysis , Air Pollutants/chemistry , Animals , Biodegradation, Environmental , Urea/metabolism , Volatilization
4.
Br Poult Sci ; 48(4): 399-405, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17701493

ABSTRACT

1. In a pen study, NH(3) flux estimates were performed when clean wheat straw or wood shavings were used as bedding materials in combination with two NH(3) control amendments: sodium bisulphate and a commercial premix of phosphoric + hydrochloric + citric acids. 2. Ammonia emissions from wood shavings were 19% greater than from wheat straw around waterers, but statistically similar around feeders. These results could be due to the greater caking observed when wheat straw was used. 3. Sodium bisulphate reduced NH(3) emissions significantly only in the first half of the rearing period; the loss of efficacy in the second half resulted in total NH(3) volatilisation not statistically different from the untreated control. The treatment containing phosphoric + hydrochloric + citric acids did not have a significant effect in decreasing NH(3) emissions. 4. Bird mortality was not affected by the treatments, but broiler weight gain when wheat straw was used was significantly lower than with wood shavings, which could have been caused by the greater caking observed with wheat straw.


Subject(s)
Ammonia/metabolism , Chickens/metabolism , Housing, Animal , Animals , Body Weight , Chickens/anatomy & histology , Chickens/growth & development , Citric Acid/chemistry , Hydrochloric Acid/chemistry , Male , Mortality , Phosphoric Acids/chemistry , Sulfates/chemistry
5.
J Environ Qual ; 34(1): 75-9, 2005.
Article in English | MEDLINE | ID: mdl-15647536

ABSTRACT

Research on nitrogen (N) mineralization from organic residues is important to understand N cycling in soils. Here we review research on factors controlling net N mineralization as well as research on laboratory and field modeling efforts, with the objective of highlighting areas with opportunities for additional research. Among the factors controlling net N mineralization are organic composition of the residue, soil temperature and water content, drying and rewetting events, and soil characteristics. Because C to N ratio of the residue cannot explain all the variability observed in N mineralization among residues, considerable effort has been dedicated to the identification of specific compounds that play critical roles in N mineralization. Spectroscopic techniques are promising tools to further identify these compounds. Many studies have evaluated the effect of temperature and soil water content on N mineralization, but most have concentrated on mineralization from soil organic matter, not from organic residues. Additional work should be conducted with different organic residues, paying particular attention to the interaction between soil temperature and water content. One- and two-pool exponential models have been used to model N mineralization under laboratory conditions, but some drawbacks make it difficult to identify definite pools of mineralizable N. Fixing rate constants has been used as a way to eliminate some of these drawbacks when modeling N mineralization from soil organic matter, and may be useful for modeling N mineralization from organic residues. Additional work with more complex simulation models is needed to simulate both gross N mineralization and immobilization to better estimate net N mineralized from organic residues.


Subject(s)
Models, Theoretical , Nitrogen/metabolism , Refuse Disposal , Soil Microbiology , Environmental Monitoring/methods , Research/trends , Spectrum Analysis
6.
J Zoo Wildl Med ; 29(2): 195-8, 1998 Jun.
Article in English | MEDLINE | ID: mdl-9732036

ABSTRACT

A Baird's tapir (Tapirus bairdii) was satisfactorily immobilized on two occasions with i.m. detomidine (0.065-0.13 mg/kg) and butorphanol (0.13-0.2 mg/kg). On the second occasion, anesthesia was induced by i.v. administration of ketamine (2.2 mg/kg). Twenty minutes later, endotracheal intubation was performed after an additional i.v. injection of ketamine (1.5 mg/kg). Anesthesia was maintained with isoflurane, which provided excellent conditions for radiology and surgery. Anesthesia was associated with hypoxemia when the tapir was allowed to breathe air and with hypoventilation. Mean arterial pressure remained satisfactory. No antagonist drugs were administered, and recovery from anesthesia was rapid and smooth.


Subject(s)
Anesthesia/veterinary , Anesthetics, Combined , Immobilization , Perissodactyla/physiology , Analgesics , Anesthetics, Dissociative , Anesthetics, Inhalation , Animals , Butorphanol , Female , Hypnotics and Sedatives , Imidazoles , Isoflurane , Ketamine
7.
Cancer Biother Radiopharm ; 13(2): 121-31, 1998 Apr.
Article in English | MEDLINE | ID: mdl-10850348

ABSTRACT

Numerous findings indicate that specific plant lectins acting against cancer could be major active components of Viscum album extracts, although activity of low molecular weight components (peptides, carbohydrates and alkaloids) might be as essential for the beneficial activity of the plain plant extracts, too. Thus, active principle of Viscum album extracts is still not understood, and is difficult to be analysed because of the complex composition of the extracts and uncertainty of the standardised effectiveness (batch consistency) of the extracts. The aims of this study were to compare the concentration dependent effects of the pure mistletoe lectin (ML-1) with the fresh plant Viscum album extract (Isorel) and its different MW components on the in vitro growth of ConA stimulated lymphocytes, on the growth and tumorigenicity (artificial lung metastases development) of murine melanoma B16F10 cells, and to compare concentration dependent effects of the different types of the Viscum album extracts in vitro (applying novel type of MTT assay). The results obtained indicate that the effects of Isorel used at high dose could be result of toxic activity of the mistletoe lectins ("ML-1 like" activity). Unlike ML-1, if used at low concentrations, Isorel selectively inhibited tumor cells, due the activity of the low MW components. On the other hand, the number of tumor nodules was reduced (in comparison to the control) equally in the lungs of mice injected with B16F10 cells pre-treated in vitro with the plain Viscum album extract or any of its modifications or ML-1. Hence, it is supposed that the beneficial therapeutic effects of Isorel might result from the combined biological activity of the high and the low MW components not lectins only. Similarly, in MTT assay low concentrations of all types of the Viscum album extract showed stronger inhibiting activity for B16F10 and HeLa cells than pure ML-1. According to these results we propose a standardisation of aqueous Viscum album extracts by comparing their and ML-1 concentration dependent activity on the tumor cells in vitro applying MTT bioassay described which should be relevant for further evaluation of their active principle and for improvement of biotherapy of cancer.


Subject(s)
Adjuvants, Immunologic/toxicity , Melanoma, Experimental/drug therapy , Plant Preparations , Plant Proteins , Toxins, Biological/toxicity , Toxins, Biological/therapeutic use , Adjuvants, Immunologic/therapeutic use , Animals , Antineoplastic Agents, Phytogenic/toxicity , Cell Division/drug effects , Cells, Cultured , HeLa Cells , Humans , Lectins/therapeutic use , Lectins/toxicity , Lymphocytes/drug effects , Lymphocytes/immunology , Male , Melanoma, Experimental/pathology , Melanoma, Experimental/secondary , Mice , Mice, Inbred C57BL , Mistletoe , Plant Extracts/toxicity , Plant Lectins , Plants, Medicinal , Ribosome Inactivating Proteins, Type 2 , Tumor Cells, Cultured
8.
Anticancer Drugs ; 8 Suppl 1: S17-22, 1997 Apr.
Article in English | MEDLINE | ID: mdl-9179362

ABSTRACT

The aim of this study was to analyse whether Viscum album (mistletoe; Isorel) modulates the tumour-host relationship and whether this might be a basic mechanism of the antitumorous activity of the drug. The effects of a single intraperitoneal injection of the drug (100 mg/kg single 'planta tota' dose) were analysed for mice-bearing melanoma B16F10 growing in the hind limb. Injection of Isorel reduced the size of the tumour and caused abundant tumour necrosis with inflammatory response, oedema and destruction of the malignant tissue. Furthermore, the lymphocytes of saline-treated tumorous mice were not able to respond to the mitogenic lectin concanavalin A in vitro, while those of mistletoe extract-treated mice showed high reactivity too the mitogen, but only if cultured in the medium supplemented with the plasma of the mistletoe extract-treated mice. Moreover, melanoma cells exposed to the mistletoe extract were more sensitive to the cytotoxic activity of the lymphocytes than the control tumour cells, particularly in the presence of the plasma of mistletoe extract-treated mice. The plasma itself, however, did not show any cytotoxic activity. These results indicate that the antitumour activity of the mistletoe drug is due to a modulation of the tumour-host relationship, mediated by direct cytotoxicity of the drug to tumour cells and/or through a potentiation of immune response by certain, as yet unidentified, growth modifying humoral factors of the host.


Subject(s)
Antineoplastic Agents, Phytogenic/therapeutic use , Melanoma, Experimental/drug therapy , Mistletoe , Phytotherapy , Plant Extracts/therapeutic use , Plants, Medicinal , Animals , Cell Division , Cells, Cultured , Lymphocytes/cytology , Melanoma, Experimental/immunology , Mice , Mice, Inbred C57BL
9.
Anticancer Drugs ; 8 Suppl 1: S27-31, 1997 Apr.
Article in English | MEDLINE | ID: mdl-9179364

ABSTRACT

The Viscum album (mistletoe) preparation Isorel is able to destroy tumour cells and to modify immune reactivity against a particular antigen in normal and in tumour-bearing animals. CBA/HZgr mice and methylcholanthrene-induced fibrosarcoma were used in these studies. A single dose of Isorel M (140 mg/kg or 1400 mg/kg body weight) significantly increased the number of plaque forming cells if applied at the time of injection of sheep red blood cells or 1 day earlier. The application of Isorel 1 day after sheep red blood cells did not modify the number of plaque forming cells in comparison to the controls. The higher the dose of Isorel the stronger is the immune response to sheep red blood cells. Furthermore, one dose of Isorel (140 mg/kg body weight) restored the suppressed immune response of fibrosarcoma-bearing mice to a significant extent. Besides modification of the humoral immune response, the survival time of C57BI/GoZgr male skin grafts on syngeneic female recipients was significantly shorter if Isorel was applied at a particular time after grafting. However, according to plaque forming cell numbers, a prolonged application of Isorel was significantly immunosuppressive in normal mice and particularly in tumour-bearing mice. It should be mentioned that the doses of Isorel used in this experiment were much higher than generally used in cancer patients. In view of the immunomodulating effects of Isorel, the monitoring of the immune response of the patients treated with mistletoe preparations is to be recommended.


Subject(s)
Adjuvants, Immunologic/therapeutic use , Antineoplastic Agents, Phytogenic/therapeutic use , Fibrosarcoma/drug therapy , Fibrosarcoma/immunology , Mistletoe , Phytotherapy , Plant Extracts/therapeutic use , Plants, Medicinal , Animals , Disease Models, Animal , Dose-Response Relationship, Drug , Erythrocytes/immunology , Female , Fibrosarcoma/chemically induced , Male , Mice , Mice, Inbred C57BL , Mice, Inbred CBA , Sheep , Skin Transplantation/immunology
10.
Arch Phys Med Rehabil ; 78(3): 319-23, 1997 Mar.
Article in English | MEDLINE | ID: mdl-9084357

ABSTRACT

This report presents a case of angiogram-confirmed pulmonary emboli (PE) from upper extremity deep venous thrombosis (UE DVT) in a patient with Guillain-Barré syndrome. UE DVT has been rarely reported in the rehabilitation literature and it is not described in many standard references in the field. Risk factors for UE DVT include central venous catheterization (CVC), stasis, and hypercoagulability. Rehabilitation patients commonly demonstrate these risk factors, as well as unilateral limb swelling and pain. Although early reports emphasized the rarity of PE from UE DVT, it is now reported in roughly 12% of cases, and there may be an even higher incidence in CVC-related UE DVT. This report includes a review of etiologic, anatomic, diagnostic, and therapeutic considerations, and concludes with a discussion of the potential underrecognized significance of UE DVT in the general rehabilitation population.


Subject(s)
Axillary Vein , Polyradiculoneuropathy/complications , Pulmonary Embolism/etiology , Subclavian Vein , Thrombosis/complications , Angiography , Anticoagulants/therapeutic use , Heparin/therapeutic use , Humans , Male , Middle Aged , Pulmonary Embolism/diagnostic imaging , Pulmonary Embolism/drug therapy , Thrombosis/drug therapy
11.
J Med Entomol ; 28(3): 410-6, 1991 May.
Article in English | MEDLINE | ID: mdl-1875368

ABSTRACT

Eastern chipmunks (Tamias striatus L.) were placed in Plexiglas cages with 0, 2, 5, 10, or 20 female Aedes triseriatus Say mosquitoes for 2 h. Previously published studies demonstrated little effective mosquito defensive behavior because of pause behavior by the chipmunks. By recording chipmunk behavior on videotape, pause behavior was reduced, and the chipmunks exhibited effective mosquito defense. The chipmunks defended themselves actively by attacking mosquitoes in flight, biting, head shaking, body turning, face grooming, hindfoot scratching, and flicking the tail. These defensive behaviors were correlated positively with the number of mosquitoes exposed to the chipmunks and with the number of mosquitoes killed.


Subject(s)
Aedes , Behavior, Animal , Sciuridae , Animals , Female , Insect Bites and Stings/veterinary , Insect Vectors
12.
Biochim Biophys Acta ; 982(1): 73-8, 1989 Jun 26.
Article in English | MEDLINE | ID: mdl-2545273

ABSTRACT

Addition of 10(-5) M amphotericin B to the tear solution of an in vitro preparation of the frog cornea increased the transepithelial conductance, gt, and decreased the apical membrane fractional resistance, f(R0), in the presence or absence of tear Na+ and Cl-. In the presence of tear Na+ and Cl-, amphotericin B increased the short-circuit current, Isc, from 3.9 to 8.8 microA.cm-2 and changed the intracellular potential, V0, from -48.5 to -17.9 mV probably due to a higher increase in the Na+ than in the K+ conductance. In the absence of tear Na+ and Cl-, amphotericin B decreased Isc from 5.5 to about 0 microA.cm-2 due to K+ (and possibly Na+) flux from cell to tear and changed V0 from -35.4 to -63.6 mV due to the increase in conductance of both ions. Increase in the tear K+ from 4 to 79 mM (in exchange for choline), in the presence of amphotericin B and absence of tear Na+ and Cl-, decreased f(R0) from 0.09 to 0.06, increased gt from 0.23 to 0.31 mS, increased Isc from 0.63 to 7.3 microA.cm-2, and changed V0 from -65.5 to -17.3 mV due to the change in EK in the presence of a high conductance in the tear membrane. Similar effects were observed with an increase of tear Na+. Results support the concept that the Na+ conductance opened by amphotericin B in the apical membrane is greater than the K+ conductance. Previously observed transepithelial effects of the ionophore may be explained mostly on the basis of its effect on the apical membrane.


Subject(s)
Amphotericin B/pharmacology , Cornea/physiology , Potassium Channels/drug effects , Potassium/physiology , Sodium Channels/drug effects , Sodium/physiology , Animals , Cell Membrane Permeability/drug effects , Electric Conductivity , In Vitro Techniques , Microelectrodes , Rana catesbeiana
14.
Am J Physiol ; 245(4): G554-61, 1983 Oct.
Article in English | MEDLINE | ID: mdl-6312811

ABSTRACT

Previously, an electrogenic Na-Cl symport was found in the fundus, and the question arises of whether there is one in the antrum, a tissue that does not secrete acid. In an in vitro preparation of the antrum of Rana catesbeiana, we found that when the [Na+] in nutrient solution was decreased (choline for Na+) the transmucosal potential difference (PD) decreased (the positivity of nutrient side decreased), and when the [Na+] was increased the PD increased. These PD changes were anomalous for Na+ but not for choline. A linear relationship for PD versus log [Na+] and not versus log [choline] excluded a choline conductive pathway. The anomalous PD response was decreased but not abolished by 10(-3) M ouabain. Normal PD responses resulted from [Na+] changes in Cl--free (SO2-4) solutions. PD responses to changes in nutrient [Cl-] were normal but decreased in the absence of Na+. Data are compatible with a passive electrogenic Na-Cl symport with more chloride than sodium ions transported per cycle, as in the fundus. Symport conductance-to-total Cl- conductance ratio is higher in antrum than in the fundus. Data from the luminal side were compatible with apical membrane conductances for Na+ and Cl-.


Subject(s)
Pyloric Antrum/physiology , Sodium/metabolism , Animals , Chlorides/pharmacology , Electric Conductivity , Furosemide/pharmacology , Mathematics , Membrane Potentials/drug effects , Models, Biological , Ouabain/pharmacology , Pyloric Antrum/drug effects , Rana catesbeiana , Sodium/pharmacology , Sodium-Potassium-Exchanging ATPase/metabolism
16.
Biochim Biophys Acta ; 727(1): 45-55, 1983 Jan 05.
Article in English | MEDLINE | ID: mdl-6600625

ABSTRACT

The effect of changing the K+ concentration in the bathing media was studied in the bullfrog antrum. Usually increasing K+ on the nutrient side in standard Cl- -containing and Cl- -free solutions decreased the transmucosal potential difference (nutrient became more negative) - a normal effect. Similar results were obtained on the secretory side. Moreover, for K+ changes on the nutrient side in Cl- media, a plot of magnitude of delta V vs. log [K+] was linear for [K+] greater than 20 mM with slope of 27 mV per 10-fold change in [K+]. However, after bathing the mucosa in Cl- media with zero K+ for about 20 min, elevating the nutrient [K+] to 4 mM increased the potential difference (V) by 4.8 mV in 5 min and repeating the same sequence increased V by 6.9 mV in 5 min - both anomalous effects. Beyond 20 mM K+ the response was normal. In SO2-4 media, an anomalous potential difference of about 1 mV was obtained for changes from 0 to 3 or 6 mM nutrient K+. Ouabain (1 X 10(-3) M) in the nutrient solution abolished the anomalous response in Cl- and SO2-4 media. The normal response is attributed to passive, conductance pathways and the anomalous response because of the effect of ouabain, to a (Na+ + K+)-ATPase pump on the nutrient-facing membrane in which more Na+ than K+ ions are transported per cycle.


Subject(s)
Potassium/pharmacology , Pyloric Antrum/physiology , Animals , Chlorides/pharmacology , Kinetics , Mathematics , Membrane Potentials/drug effects , Models, Biological , Ouabain/pharmacology , Pyloric Antrum/drug effects , Rana catesbeiana
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