scholarly journals Effect of intraruminal infusion of potassium on the site of magnesium absorption within the digestive tract in sheep

1997 ◽  
Vol 129 (1) ◽  
pp. 99-105 ◽  
Author(s):  
D. E. DALLEY ◽  
P. ISHERWOOD ◽  
A. R. SYKES ◽  
A. B. ROBSON
Keyword(s):  
Digestive Tract ◽  
Solid Phase ◽  
Latin Square ◽  
Cerium Chloride ◽  
Faecal Excretion ◽  
Absorption Increase ◽  
High K ◽  
Before And After ◽  
Lincoln University ◽  
Female Sheep

Sixteen 2-year old female sheep were fitted with ruminal and duodenal cannulae at Johnstone Memorial Laboratory, Lincoln University during 1989–90. They were offered, at 2 hourly intervals, a pelleted concentrate diet (900 g/day) and chaffed lucerne hay (100 g/day). In a split-plot experiment they were infused, intraruminally and at four rates, with potassium (providing 16, 26, 36 or 46 g K/kg food DM/day) and magnesium (providing 1·3, 1·8, 2·3 or 3·1 g Mg/kg food DM/day) within a Latin square design and with the liquid and solid phase markers 51chromium EDTA and 141cerium chloride. Net absorption of Mg before and after the duodenum was estimated from dietary intake, duodenal flow and urinary and faecal excretion of Mg.Increasing K intake resulted in a decline in net absorption of Mg from the entire digestive tract, supporting data in the literature. Increasing K intake from 16 to 46 g/kg DM decreased urinary Mg excretion by between 0·14 and 0·30 g/day, the extent of which was independent of the level of Mg intake. At high K intake Mg absorption from the rumen was reduced, the amount absorbed ranging from 0·07 g Mg/day at intakes of 1·3 g Mg/day and 46 g K/kg DM/day to 0·66 g Mg/day at intakes of 3·1 g Mg/day and 16 g K/kg DM/day. However, at high K intake, and when Mg absorption from the rumen was reduced, net Mg absorption from sites distal to the rumen was increased to an extent which suggested compensatory absorption. Increase in K intake was associated with a consistent reduction in plasma Mg concentration which was independent of Mg intake. Increases in Mg intake resulted in increases in Mg absorption and plasma Mg concentration at all rates of K intake in direct proportion to rate of intake. The reduction in Mg absorption from the rumen at high K intake was associated with an increase (0·3 units) in pH of rumen digesta.

ANALYSIS OF RADIOIMMUNOASSAY BY DISC ELECTROPHORESIS AND SUCROSE GRADIENT CENTRIFUGATION

1971 ◽  
Vol 66 (2) ◽  
pp. 257-265 ◽  
Author(s):  
Lubomir Valenta ◽  
Michel L. Aubert
Keyword(s):  
Sucrose Gradient ◽  
Solid Phase ◽  
Gradient Centrifugation ◽  
Human Growth ◽  
Disc Electrophoresis ◽  
Separate Analysis ◽  
Adrenocorticotrophic Hormone ◽  
Sucrose Gradient Centrifugation ◽  
Before And After ◽  
Polypeptide Hormones

ABSTRACT Radioiodine-labelled synthetic adrenocorticotrophic hormone (ACTH), human growth hormone (HGH), human chorionic somato-mammotrophin (HCS), and human (HTSH) and bovine (BTSH) thyroid stimulating hormones were studied by disc-electrophoresis and sucrose gradient centrifugation before and after incubation with corresponding antisera. All antisera contained 7 S antibodies. After incubation, soluble antigenantibody complexes besides a small amount of precipitate were observed in the incubation mixture, characteristic of each hormone. The complexes migrated like gamma globulins or more slowly on disc-electrophoresis. and on sucrose gradient centrifugation showed patterns dependent on the time of incubation. Light 7 or 9 S, or < 12 S complexes occurred mostly after incubation for several minutes (up to 30 min) before analysis. When incubation was prolonged to 24 h and more, these relatively light complexes disappeared or diminished in favour of heavier soluble or precipitating complexes. Reproducibly obtainable sedimentation patterns of the soluble complexes suggested some definite recombination of antigen molecules with 7 S antibodies. The complexes did not occur on incubation with other sera than an antiserum to a given hormone. They were not influenced by EDTA. Displacement of the radioactivity of the complexes into the free hormone peak was obtained by addition of a non-labelled hormone identical with the labelled one. Sucrose gradient centrifugation and disc-electrophoresis are recommended for the study of immunoreaction of diluted materials and for a separate analysis of different steps of the radioimmunoassay. Radioimmunoassay was introduced for the measurement of protein hormones by Yalow & Berson (1960). The method, described originally for insulin, was later adapted to the detection of a number of protein and polypeptide hormones. On incubation of the hormone with its antiserum, a soluble antigenantibody complex is formed, which is separated from an excess of the free hormone by various methods, e. g. chromatoelectrophoresis, precipitation with a second antibody, adsorption on a solid phase etc. (Hunter 1967). Sucrose gradient centrifugation and disc-electrophoresis were occasionally used to follow some isolated aspect of radioimmunoassay (Fitschen 1965; Monjardino et al. 1968). We are demonstrating that these methods made it possible to analyze the radioimmunoassay step by step and thus may be useful for practical purposes as well as in a study of the immunoreaction of diluted materials.

Comparative Study on Compositions of Oil-Water Transition Layer before and after ClO2-Treatment Process

2013 ◽  
Vol 652-654 ◽  
pp. 749-752
Author(s):  
Dan Dan Yuan ◽  
Hong Jun Wu ◽  
Hai Xia Sheng ◽  
Xin Sui ◽  
Bao Hui Wang
Keyword(s):  
Chemical Composition ◽  
Transition Layer ◽  
Solid Phase ◽  
Settling Tank ◽  
Physical Structure ◽  
Solid Particles ◽  
Viscosity Reduction ◽  
Insoluble Residue ◽  
Before And After ◽  
Oil Water

In order to meet the need of separating oil from water in the settling tank of the oilfield, ClO2 treatment for oil-water transition layer in settling tank is introduced. The field test displayed that the technique was achieved by a good performance. For understanding the oxidation and mechanism, compositions of oil-water transition layer were comparatively studied for before/after ClO2-treatment in this paper.The experimental results show that the compositions before and after ClO2-treatment, including physical structure and chemical composition, were varied in the great extension. The physical structure, consisting of water, oil and solid phase, was reduced to less than 5% of water and 0.5% of solid particle and increased to 95% of oil in layer compared with before-treatment, easily leading to clearly separating water from oil. The chemical composition of iron sulfide and acid insoluble substance in solid phase was decreased to more than 90% while the carbonate was reduced more than 70% . After the treatment, the viscosity reduction of the water phase in the layer was reached to 50% after oxidation demulsification with ClO2. The chemistry was discussed based on the principles and experiments. Due to ClO2 destroying (oxidizing) the rigid interface membrane structure which is supported by natural surfactant, polymer and solid particles with interface-active materials, the action accelerates the separating of water and oil and sedimentation of insoluble residue of acid in the layer. By demonstrating the experimental data and discussion, we can effectively control the oxidation performance of chlorine dioxide, which is very meaningful for oilfield on the aspect of stable production of petroleum.

scholarly journals A Diagnostic Solution for Lupus Anticoagulant Testing in Patients Taking Direct Oral FXa Inhibitors Using DOAC Filter

2021 ◽  
Vol 8 ◽  
Author(s):  
Carine Farkh ◽  
Syrine Ellouze ◽  
Louis Gounelle ◽  
Mama Sad Houari ◽  
Jérôme Duchemin ◽  
...  
Keyword(s):  
Lupus Anticoagulant ◽  
Solid Phase ◽  
Covalent Binding ◽  
Plasma Concentrations ◽  
Factor Xa ◽  
New Device ◽  
Before And After ◽  
Single Use ◽  
Fxa Inhibitor ◽  
Inhibitor Compounds

Background: Direct oral factor Xa (FXa) inhibitors interfere with lupus anticoagulant (LA) assays challenging antiphospholipid syndrome diagnosis in treated patients. We evaluated a new device, called DOAC Filter, and its usefulness in this setting. It is a single-use filtration cartridge in which FXa inhibitor compounds are trapped by non-covalent binding while plasma is filtered through a solid phase. Patient samples were analyzed before and after filtration: 38 rivaroxaban, 41 apixaban, and 68 none. Anticoagulant plasma concentrations were measured using specific anti-Xa assays and HPLC-MS/MS. LA testing was performed using dilute Russell Viper Venom Time (dRVVT) and Silica Clotting Time (SCT). Baseline median [min–max] concentrations were 64.8 [17.6; 311.4] for rivaroxaban and 92.1 ng/mL [37.1; 390.7] for apixaban (HPLC-MS/MS). They were significantly correlated with anti-Xa assay results (r = 0.98 and r = 0.94, respectively). dRVVT was positive in 92% rivaroxaban and 72% apixaban and SCT in 28 and 41% of samples, respectively. Post-filtration, median % of neutralization was 100% with rivaroxaban and apixaban concentrations of, respectively, &lt;2 [&lt;2–2.4] and &lt;2 ng/mL [&lt;2–9.6] using HPLC-MS/MS. No significant effect of DOAC Filter was observed on LA testing in controls (n = 31) and LA-positive (n = 37) non-anticoagulated samples. dRVVT and SCT remained positive in, respectively, 16 and 8% of rivaroxaban and 41 and 18% of apixaban samples. DOAC Filter would be an easy-to-use device allowing FXa inhibitor removal from plasma samples, limiting their interference with LA testing in treated patients.

scholarly journals Obtaining the conductive SnO2 films by chemical bath deposition method

2019 ◽  
Vol 60 (11) ◽  
pp. 1-10
Author(s):  
Vladislav I. Rogozin ◽  
◽  
Vyacheslav F. Markov ◽  
Larisa N. Maskaeva ◽  
Anastasia E. Krasovskaya ◽  
...  
Keyword(s):  
Tin Dioxide ◽  
Solid Phase ◽  
Average Particle Size ◽  
Ammonium Fluoride ◽  
Contact Layer ◽  
Average Particle ◽  
Solution Ph ◽  
Before And After ◽  
Initial Salt ◽  
Conductive Properties

Thanks to such unique properties as transparency and conductivity tin dioxide often utilize as transparent contact layer to produce displays, solar cells, and sensor devices. Hydrochemical method of deposition SnO2 films is a perspective due to its simplicity, and economical efficiency. The ionic equilibria analysis was carried out and the boundary conditions of Sn(OH)2 solid phase formation in the «Sn2+ – H2O – OH‾» system calculated. It was established, that tin(II) hydroxide may be obtain in the range 2 < pH < 12. Preliminary results allow to determinate an optimal mixture sourness interval 1 < pH < 5. Revealed, that the thickness of the Sn(OH)2 films strongly depends on the solution pH. Maximum value of 488 nm reached at pH = 8. Conductive SnO2 layers were obtained on a glass and sitall substrates with simultaneously presence of antimony chloride and ammonium fluoride followed by annealing in air. The thickness vs temperature and thickness vs tin initial salt concentration dependences were installed. The uniform tin hydroxide layers with a thickness of ~74 nm may be synthesized under pH = 2 conditions. By the electron microscopy method the average particle size was established changing from 200 to 400 nm for as-synthesized films, to ~20 nm for annealed which indicates the nanostructure nature of the films. The morphology, elemental composition and conductive properties of deposited films were investigated before and after heating stage. Studying the annealing temperature influence at the film resistance were identified a three temperature ranges within which the films sharply differ in their conductive properties, which is associated with phase and structural transformations in them. Shown, that the most conductive SnO2 films with the omic resistance 3-5 kOm/sm were obtained at the temperature range 620-870 K.

scholarly journals Cannabinoids in Exhaled Breath following Controlled Administration of Smoked Cannabis

2013 ◽  
Vol 59 (12) ◽  
pp. 1780-1789 ◽  
Author(s):  
Sarah K Himes ◽  
Karl B Scheidweiler ◽  
Olof Beck ◽  
David A Gorelick ◽  
Nathalie A Desrosiers ◽  
...  
Keyword(s):  
Solid Phase Extraction ◽  
Time Course ◽  
Matrix Effects ◽  
Solid Phase ◽  
Driving Under The Influence ◽  
Phase Extraction ◽  
Exhaled Breath ◽  
C Storage ◽  
Before And After ◽  
Occasional Smoker

BACKGROUND Δ9-Tetrahydrocannabinol (THC), 11-nor-9-carboxy-THC (THCCOOH), and cannabinol (CBN) were measured in breath following controlled cannabis smoking to characterize the time course and windows of detection of breath cannabinoids. METHODS Exhaled breath was collected from chronic (≥4 times per week) and occasional (&lt;twice per week) smokers before and after smoking a 6.8% THC cigarette. Sample analysis included methanol extraction from breath pads, solid-phase extraction, and liquid chromatography–tandem mass spectrometry quantification. RESULTS THC was the major cannabinoid in breath; no sample contained THCCOOH and only 1 contained CBN. Among chronic smokers (n = 13), all breath samples were positive for THC at 0.89 h, 76.9% at 1.38 h, and 53.8% at 2.38 h, and only 1 sample was positive at 4.2 h after smoking. Among occasional smokers (n = 11), 90.9% of breath samples were THC-positive at 0.95 h and 63.6% at 1.49 h. One occasional smoker had no detectable THC. Analyte recovery from breath pads by methanolic extraction was 84.2%–97.4%. Limits of quantification were 50 pg/pad for THC and CBN and 100 pg/pad for THCCOOH. Solid-phase extraction efficiency was 46.6%–52.1% (THC) and 76.3%–83.8% (THCCOOH, CBN). Matrix effects were −34.6% to 12.3%. Cannabinoids fortified onto breath pads were stable (≤18.2% concentration change) for 8 h at room temperature and −20°C storage for 6 months. CONCLUSIONS Breath may offer an alternative matrix for identifying recent driving under the influence of cannabis, but currently sensitivity is limited to a short detection window (0.5–2 h).

The Effect of Level of Supplement Feeding and Source of Protein on Milk Production and Nutrient Flows of Dairy Cows

1994 ◽  
Vol 1994 ◽  
pp. 142-142
Author(s):  
F.P. O'Mara ◽  
J.J. Murphy ◽  
M. Rath
Keyword(s):  
Protein Synthesis ◽  
Dairy Cows ◽  
Milk Production ◽  
Milk Protein ◽  
Solid Phase ◽  
Latin Square ◽  
Nutrient Flows ◽  
Grass Silage ◽  
Bacterial Marker ◽  
Friesian Cows

Milk protein synthesis may be limited by amino acid (AA) flow to the duodenum. This can be increased by increasing the flow of microbial AA's or undegraded feed AA's. This experiment was carried out to determine the effect on milk production and nutrient flows at the duodenum of including fishmeal (120g/kg) in the supplement to grass silage at two levels of supplement feeding.The treatments, arranged in a 2x2 factorial, were 1.) 3.5 kg/day of 0% fishmeal supplement (L-UDP), 2.) 7 kg/day of L-UDP, 3.) 3.5 kg/day of 12% fishmeal supplement (H-UDP), and 4.) 7 kg/day of H-UDP. Supplements were fed to 3 6 Friesian cows in a 4x4 multiple Latin-square trial with three week periods to determine production responses, and to four ruminally and duodenally cannulated cows to determine rumen fermentation and nutrient flows. Flows were determined by the dual marker technique of Faichney (1975) using cobalt-EDTA and ytterbium acetate as liquid and solid phase markers respectively. Purines were used as the bacterial marker (Zinn and Owens, 1986). Degradability of the feeds was measured in 3 other cows using the small bag technique described by De Boer et al. (1987).

Fluid and Solute Transport in CAPD Patients before and after Permanent Loss of Ultrafiltration Capacity

2005 ◽  
Vol 28 (10) ◽  
pp. 976-984 ◽  
Author(s):  
J. Waniewski ◽  
D. Sobiecka ◽  
M. DĘbowska ◽  
O. Heimbürger ◽  
A. Werynski ◽  
...  
Keyword(s):  
Solute Transport ◽  
Absorption Rate ◽  
Fluid Absorption ◽  
Transport Parameters ◽  
Normal Range ◽  
Peritoneal Transport ◽  
High K ◽  
Before And After ◽  
Permanent Loss ◽  
High Fluid

Background Two major types of permanent loss of ultrafiltration capacity (UFC) were previously distinguished among patients treated with CAPD: 1) type HDR with high diffusive peritoneal transport rate of small solutes and low osmotic conductance, but with normal fluid absorption rate, and 2) type HAR with high fluid absorption rate, but with normal diffusive peritoneal transport rate of small solutes and normal osmotic conductance. However, the detailed pattern of changes in peritoneal transport parameters in patients developing loss of ultrafiltration capacity is not known. Objective Analysis of solute and fluid transport parameters in the same patient before and after UFC loss. Patients Seven CAPD patients who had undergone repeated dwell studies, which were carried out before and/or after the onset of UFC loss. Methods Dialysis fluids (2 L) with glucose or a mixture of amino acids as osmotic agent at three basic tonicities were applied during 6 hour dwell studies. Fluid and solute transport parameters were previously shown not to be affected by these dialysis solutions (except by hypertonic amino acid-based solution). Intraperitoneal dialysate volume and fluid absorption rate were assessed using radiolabeled human serum albumin (RISA). Osmotic conductance (aOS) was estimated by a mathematical model as ultrafiltration rate induced by unit osmolality gradient. Diffusive mass transport coefficients, KBD, for glucose, urea, and creatinine were estimated using the modified Babb-Randerson-Farrell model. Results Five patients had increased KBD for small solutes after the onset of UFC loss, and three of them had decreased aOS, whereas two patients had normal aOS. In one of them, aOS decreased with time after the onset of UFC loss with concomitant normalization of glucose absorption. In all studies of these five patients the fluid absorption rate was within the normal range. Two other patients had increased fluid absorption rate (about 5 ml/min), and one of them also had increased KBD for small solutes, in two consecutive dwell studies in each patient with the second study being carried out at 1 and 7 months respectively after the first one. In all four studies in these two patients, the aOS was within the normal range. The sodium dip during dialysis with 3.86% glucose-based solution was lost, not only among most patients with UFC loss related to reduced osmotic conductance, but also in patients with increased KBD. Conclusions The occurrence of two major types of UFC loss was confirmed. However, a case of a mixed type of UFC loss with high fluid absorption rate and high KBD for small solutes, but normal osmotic conductance, and with normalization of initially high KBD for small solutes, linked with decreasing initially normal osmotic conductance, was also found. As a reduced sodium dip with hypertonic glucose solution is not only seen in patients with reduced osmotic conductance, it cannot reliably be used as a single measure of decreased aquaporin function. Permanent ultrafiltration capacity loss may be a dynamic phenomenon with a variety of alterations in peritoneal transport characteristics.

Role of extracellular Ca2+ in diaphragmatic contraction: effects of ouabain, monensin, and ryanodine

1992 ◽  
Vol 73 (1) ◽  
pp. 30-35 ◽  
Author(s):  
J. H. Zavecz ◽  
W. M. Anderson
Keyword(s):  
Relaxation Time ◽  
Free Solution ◽  
Pharmacological Agents ◽  
Resting Tension ◽  
High K ◽  
Before And After ◽  
Small Muscle ◽  
Ionophore Monensin

The effects of zero extracellular Ca2+ on the contractility of rat diaphragmatic strips in vitro were studied in conjunction with various pharmacological agents known to influence the intracellular Ca2+ concentration: the Na+ ionophore, monensin, and the Na(+)-K+ pump inhibitor, ouabain, which enhance [Ca2+]i, caffeine, which induces Ca2+ release from the sarcoplasmic reticulum (SR), and ryanodine, which prevents Ca2+ retention by the SR. The effect of increasing [Ca2+]i on diaphragmatic contraction was assessed by comparing contractions induced by 120 mM K+ in the small muscle strips before and after the addition of ouabain or monensin. Monensin (20 microM) and ouabain (1–100 microM) augmented contractions up to threefold. Treatment of diaphragm strips with 3 nM ryanodine increased baseline tension 360% above the original resting tension but only if the diaphragm was electrically stimulated concurrently; 100 microM ryanodine induced contracture in quiescent tissue. High K+ contractures were of greater magnitude in the presence of ryanodine compared with control, and relaxation time was prolonged by greater than 200%. Ca(2+)-free conditions ameliorated these actions of ryanodine. Ryanodine reduced contractions induced by 10 mM caffeine and nearly abolished them in Ca(2+)-free solution. The data demonstrate that extracellular Ca2+ is important in certain types of contractile responses of the diaphragm and suggest that the processes necessary to utilize extracellular Ca2+ are present in the diaphragm.

scholarly journals Effects of passage through the digestive tract on incretin secretion: Before and after birth

2020 ◽  
Author(s):  
Seiichi Tomotaki ◽  
Ryosuke Araki ◽  
Kouji Motokura ◽  
Yutaro Tomobe ◽  
Takeru Yamauchi ◽  
...  
Keyword(s):  
Digestive Tract ◽  
Before And After ◽  
Incretin Secretion
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