A Rapid And Sensitive Method For The Quantitation Of Platelet Autoantibodies

1981 ◽  
Author(s):  
F Jacks ◽  
B A Bradlow
Keyword(s):  
Room Temperature ◽  
Specific Activity ◽  
Dose Range ◽  
Blood Platelet ◽  
Gamma Spectrometer ◽  
Microtitre Plate ◽  
Standard Curve ◽  
Specific Igg ◽  
Iodine 125 ◽  
Phosphate Buffered Saline

Autoantibodies were solubilized from washed platelets by three successive freeze thaw cycles followed by sonication for 15 seconds at maximum intensity (MSE Mk 2). The disrupted platelets were centrifuged at 30,000g for 20 minutes and the supernatant was heated at 56°C for 30 minutes followed by centrifugation at 3,000g for 5 minutes. An aliquot of the supernatant was diluted with 0,01M phosphate buffered saline pH 7.4 to give a final concentration equivalent to about 5 × 106 platelets/ml. Fifty microlitres of the diluted extract was adsorbed onto the wells of a microtitre plate by incubation at room temperature for two hours. The wells were then washed three times with 0,01M phosphate buffered saline pH 7.4 containing 0,05% Tween (Tween-PBS) and the adsorbed antiplatelet IgG reacted with 50μl of an iodine-125 labelled affinity isolated goat antihuman (heavy chain specific) IgG, specific activity ≃ 50μCi/ μg (California Antibodies) for one hour at room temperature followed by three washes with Tween-PBS. A standard curve was constructed and run in parallel, in the dose range 0,l-100ng using purified human IgG (Miles Laboratories). The separated wells were counted in an automatic gamma spectrometer (Packard 3003) and the results calculated on a desk-top computer (Hewlet-Packard 9800) using a Rodbart weighted Logit-Log transformation (f = 0,996). A relatively poor arithmetic correlation was found between whole blood platelet counts and measured platelet bound IgG (r = -0,42), whereas a better correlation was obtained using a log-log plot (r = - 0,84).The results in ng/106 platelets were - Known ATP 133,2 ± 154, other autoimmune diseases with thrombocytopenia 212,0 ± 202, non-immune thrombocytopenia 18,6 ± 4,8, normal healthy controls 11,4 ± 3.7

Method of Non-Destructive Measurement of Natural Radionuclides Concentration in Building Materials

ANRI ◽  
2021 ◽  
Vol 0 (1) ◽  
pp. 31-44
Author(s):  
Aleksey Vasil'ev ◽  
Aleksey Ekidin ◽  
Mariya Pyshkina ◽  
Georgiy Malinovskiy ◽  
Aleksandra Onischenko ◽  
...  
Keyword(s):  
Gamma Radiation ◽  
Flux Density ◽  
Building Materials ◽  
Specific Activity ◽  
Natural Radionuclides ◽  
Gamma Spectrometer ◽  
Average Activity ◽  
Destructive Measurement ◽  
Non Destructive ◽  
Calculated Flux

A method for non-destructive monitoring of the content of natural radionuclides in building materials has been developed. Spectrum measurements of gamma radiation are carried out with a pre-calibrated field gamma spectrometer. The calculation of the average specific activity of natural radionuclides in building materials is carried out by comparing the calculated flux density of unscattered gamma quanta normalized to the specific activity, and the experimentally measured count rates in the photopeak. calculated for the geometry of the room under study and the location of the detector. Application of the developed method makes it possible to estimate the average activity of natural radionuclides in building materials without destruction.

Mitigating the Antimicrobial Activities of Selected Organic Acids and Commercial Sanitizers with Various Neutralizing Agents

2011 ◽  
Vol 74 (5) ◽  
pp. 820-825 ◽  
Author(s):  
YOEN JU PARK ◽  
JINRU CHEN
Keyword(s):  
Escherichia Coli ◽  
Acetic Acid ◽  
Lactic Acid ◽  
Organic Acids ◽  
Shiga Toxin ◽  
Room Temperature ◽  
Sodium Thiosulfate ◽  
Antimicrobial Activities ◽  
Phosphate Buffered Saline ◽  
Lactic Acids

This study was conducted to evaluate the abilities of five neutralizing agents, Dey-Engley (DE) neutralizing broth (single or double strength), morpholinepropanesulfonic acid (MOPS) buffer, phosphate-buffered saline (PBS), and sodium thiosulfate buffer, in mitigating the activities of acetic or lactic acid (2%) and an alkaline or acidic sanitizer (a manufacturer-recommended concentration) againt the cells of Shiga toxin–producing Escherichia coli (STEC; n = 9). To evaluate the possible toxicity of the neutralizing agents to the STEC cells, each STEC strain was exposed to each of the neutralizing agents at room temperature for 10 min. Neutralizing efficacy was evaluated by placing each STEC strain in a mixture of sanitizer and neutralizer under the same conditions. The neutralizing agents had no detectable toxic effect on the STEC strains. PBS was least effective for neutralizing the activity of selected organic acids and sanitizers. Single-strength DE and sodium thiosulfate neutralized the activity of both acetic and lactic acids. MOPS buffer neutralized the activity of acetic acid and lactic acid against six and five STEC strains, respectively. All neutralizing agents, except double-strength DE broth, had a limited neutralizing effect on the activity of the commercial sanitizers used in the study. The double-strength DE broth effectively neutralized the activity of the two commercial sanitizers with no detectable toxic effects on STEC cells.

scholarly journals PEMBUATAN RADIONUKLIDA MOLIBDENUM-99 (99Mo) HASIL AKTIVASI NEUTRON DARI MOLIBDENUM ALAM UNTUK MEMPEROLEH TEKNESIUM-99m (99mTc)

2016 ◽  
Vol 22 (2) ◽  
Author(s):  
Indra Saptiama ◽  
Herlina Herlina ◽  
Sriyono Sriyono ◽  
E. Sarmini ◽  
Abidin Abidin ◽  
...  
Keyword(s):  
Fission Product ◽  
Specific Activity ◽  
Target Material ◽  
Gamma Spectrometer ◽  
Quartz Ampule ◽  
Radionuclide Separation ◽  
Outer Capsule ◽  
Parent Radionuclide ◽  
Daughter Radionuclide ◽  
Uranium Fission

PEMBUATAN RADIONUKLIDA MOLIBDENUM-99 (99Mo) HASIL AKTIVASI NEUTRON DARI MOLIBDENUM ALAM UNTUK MEMPEROLEH TEKNESIUM-99m (99mTc). Pembatasan penggunaan uranium sebagai target untuk produksi 99mTc menyebabkan rumah sakit di Indonesia  kesulitan mendapatkan pasokan 99mTc. Saat ini 99mTc diperoleh dari 99Mo hasil fisi (pembelahan uranium).  Pembuatan radionuklida 99Mo dari aktivasi neutron  molibdenum alam (MoO3) di teras reaktor G.A Siwabessy digunakan sebagai metode alternatif untuk memperoleh 99mTc. Tujuan penelitian ini adalah untuk melakukan pembuatan radionuklida 99Mo dari aktivasi neutron molibdenum alam untuk memperoleh 99mTc. Serbuk MoO3 alam sebanyak 5 gram dikemas dalam ampul kuarsa dan dimasukkan ke dalam inner capsul selanjutnya dikemas menggunakan outer capsul sebagai bahan target. Bahan target diiradiasi di reaktor G.A Siwabessy selama 100 jam. Hasil perhitungan diperoleh aktivitas  99Mo sebesar 65 % dari nilai maksimum yang dapat diperoleh. MoO3 paska iradiasi dilarutkan dengan NaOH 4 M sehingga diperoleh larutan natrium molibdat (Na2MoO4). Radionuklida 99Mo dan 99mTc diukur menggunakan spektrometer gamma. Radionuklida 99Mo terdeteksi dalam produk larutan  Na2MoO4 dengan  aktivitas jenis 99Mo yang diperoleh sebesar 0,81 Ci 99Mo/g Mo.  Radionuklida anak luruh 99mTc dipisahkan dari radionuklida induk 99Mo menggunakan kolom pemisah yang berisi material berbasis zirkonium (MBZ) sebagai penyerap 99Mo. Radionuklida 99mTc hasil pemisahan diperoleh dalam bentuk natrium pertehnetat (Na99mTcO4).dengan recovery yang masih rendah yaitu sekitar 52 hingga 71 %.Kata kunci: Molibdenum, teknesium, radionuklida, pemisahan, iradiasi. PRODUCTION OF ACTIVATED  NEUTRON MOLYBDENUM-99 (99Mo) RADIONUCLIDE FROM NATURAL MOLYBDENUM TO OBTAIN TECHNETIUM-99m (99mTc).  Uranium usage restriction causes the hospitals in indonesia difficult to obtain the suply of  99mTc. At Present, 99mTc is obtanied from molybdenum as a uranium fission product. Production of 99Mo radionuclide resulted from neutron activated natural molybdenum (MoO3) in G.A Siwabessy reactor could be used  as a alternatif method for producing 99mTc. The aim of this research is synthesize of   99Mo radionuclide from neutron activated natural molybdenum  (MoO3) to obtain 99mTc. The five grams of  MoO3 powder was packed in a quartz ampule and inserted into inner capsule then also inserted into outer capsule as a target material. It was iradiated in G.A Siwabessy reactor for 100hours. Based on theoritical calculation, about 65 % of maximum 99Mo activity could be recovered. After Irradiation,  MoO3 was dissolved by NaOH 4 M solution so it was natrium molybdate (Na2MoO4) solution. 99Mo and 99mTc radionuclide were analyzed using gamma spectrometer. 99Mo radionuclide was detected on Na2MoO4 solution as product that had specific activity of 0.81 Ci 99Mo/ g Mo. 99mTc as daughter radionuclide was separated from 99Mo as parent radionuclide using separated column containing zirconium based material (ZBM) as 99Mo adsobent. 99mTc radionuclide has been succesfully separated using ZBM column although recovery of 99mTc  was quite low in which approximately 52 to 71 %. The 99mTc radionuclide was recovered in the form of sodium pertechnetate (NaTcO4) solution.Keywords: Molybdenum, technetium, radionuclide, separation, irradiation.

Development of Direct Competitive ELISA Kit for the Detection of Tetrodotoxin Using HRP Labeled Antigen

2011 ◽  
Vol 236-238 ◽  
pp. 2820-2824 ◽  
Author(s):  
Qing Ping Zhong ◽  
An Cheng Huang ◽  
Bin Wang ◽  
Xue Dong
Keyword(s):  
Room Temperature ◽  
Inhibitory Concentration ◽  
Enzyme Linked Immunosorbent Assay ◽  
Competitive Reaction ◽  
Antigen Concentration ◽  
Time Saving ◽  
Elisa Kit ◽  
Standard Curve ◽  
Coating Method ◽  
Ml Detection

The direct competitive enzyme-linked immunosorbent assay (dcELISA) kit was developed for detecting tetrodotoxin (TTX). The working conditions of the dcELISA kit including the anti-TTX mAb coating concentration, coating method, enzyme-labeled antigen concentration, the antigen diluents, reaction time and temperature were all optimized. The result showed that mAb coating concentration was 3.72 μg/ml, it was coated at the condition of minimal power treatment of microwave oven for 3 min. The enzyme-labeled antigen concentration was 4.08 μg/ml. The competitive reaction was under the condition of room temperature 25 °C for 30 min. The half maximal inhibitory concentration (IC50) of the standard curve was 20.4 ng/ml, detection limit was 1.1 ng/ml, linear range 3.3～137 ng/ml, the intra-assay CV and inter-assay CV were 6.25% and 7.34% respectively. And recovery rate of TTX ranged from 65.0% to 93.2% with the CV of 9.41～12.77%. This method is convenient, sensitive and time-saving, hope this dcELISA kit can bring benefits and reference for TTX detection.

PROPERTIES OF BOVINE Ac-GLOBULIN CONCENTRATES AND METHODS OF PREPARATION

1963 ◽  
Vol 41 (1) ◽  
pp. 2409-2421 ◽  
Author(s):  
Nobuo Aoki ◽  
Charles R. Harmison ◽  
Walter H. Seegers
Keyword(s):  
Human Plasma ◽  
Ammonium Sulphate ◽  
Protein Concentration ◽  
Room Temperature ◽  
Specific Activity ◽  
Barium Carbonate ◽  
Dry Weight ◽  
Physical Chemical ◽  
Bovine Plasma ◽  
Refrigerator Temperature

A procedure is described for retaining bovine plasma Ac-globulin activity as one part of the protein from plasma for every 1000 parts removed. The yields averaged 15%. The procedure involves removal of prothrombin with barium carbonate, isoelectric fractionation, fractionation with ammonium sulphate, chromatography on Amberlite IRC-50, and a second fractionation with ammonium sulphate. The procedure requires 2 days; however, the first day completes up to chromatography and the concentrate at that time is quite useful for many purposes. It is more stable than the product obtained after chromatography and the yields are higher. In absence of salts Ac-globulin is quite insoluble at pH 5.0. The final product usually contained some impurity. With the analytical ultra-centrifuge the S20in 0.1 M potassium chloride solution was found to be 4.2 at a protein concentration of 12.4 mg/ml. The specific activity was 1500 U./mg dry weight. Bovine plasma contains 120 U./ml or about 9 mg/100 ml. Assuming the same specific activity for human plasma the concentration is most likely near 1 mg/100 ml. The best stability conditions found were: 50% glycerol, pH 7.0, and 0.1 M calcium chloride. Under those conditions at room temperature all activity was retained 6 to 7 hours, at refrigerator temperature 24 hours, and at −60 °C for 1 month. In rabbits, antibodies were readily produced. Oxidizing agents destroyed the activity, while reducing agents did not, nor did they tend to stabilize. SH blocking agents destroyed the activity. The loss of activity in the presence of 0.0025 M parachloromercuribenzoate was recovered with 0.04 M cysteine. The molecule deteriorated while attempts were made to obtain physical chemical data; consequently, the molecular weight was calculated from an amino acid analysis and found to be 98,800. The reliability of this value is problematical. Human plasma was analyzed and found to contain 13 U./ml Ac-globulin. After 4 days storage, at room temperature, the prolonged prothrombin time of that plasma was completely restored with 13 units of Ac-globulin, which is equivalent to 8 μg.

Fluid and electrolyte changes of thyroidectomized rats in a cold environment

1959 ◽  
Vol 196 (6) ◽  
pp. 1214-1217 ◽  
Author(s):  
Joseph B. Boatman ◽  
John M. Walsh ◽  
Leonard I. Epstein ◽  
Marvin J. Rabinovitz
Keyword(s):  
Cold Exposure ◽  
Room Temperature ◽  
Specific Activity ◽  
Albino Rats ◽  
Cold Environment ◽  
Total Water ◽  
Tissue Water Content ◽  
Tissue Water ◽  
Sodium Potassium ◽  
Sodium Flux

Groups of adult male albino rats were thyroidectomized or sham-operated, and later subjected to 10 day, 5°C cold exposure or else maintained at 22°C room temperatures. Tissues were examined for total water, sodium, potassium, Na24 and I131-thyroxine distribution. Thyroidectomized animals in the cold showed significantly greater amounts of water and Na24 specific activity in muscle and brain. Sham-operated animals in the cold showed significantly reduced brain Na24 specific activity. Thyroxine I131/Na24 ratios in tissue were greater at room temperature in thyroidectomized animals and were decreased with cold. Sham-operated animals showed no differences in brain thyroxine I131/Na24 ratios after equilibration and small differences in muscle ratios, with cold. It was concluded that a cold environment imposed on thyroidectomized animals resulted in changes in the animal's capacity to readjust body fluids and electrolytes when compared with intact animals exposed to cold. These differences were attributable to greater tissue water content and increased sodium flux into the tissues.

Single-reagent polarization fluoroimmunoassay for barbiturates in urine.

1984 ◽  
Vol 30 (11) ◽  
pp. 1765-1769 ◽  
Author(s):  
D L Colbert ◽  
D S Smith ◽  
J Landon ◽  
A M Sidki
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Fluorescence Polarization ◽  
Room Temperature ◽  
Cross Reactivity ◽  
Screening Techniques ◽  
Standard Curve ◽  
Layer Chromatography

Abstract We describe a rapid polarization fluoroimmunoassay for screening for the presence of barbiturates in urine. The single reagent is prepared by pre-mixing antiserum with a fluorescein-labeled barbiturate derivative as tracer. Use of a mixture of two sheep antisera, raised against different barbiturate immunogens, results in an assay with a broad cross-reactivity spectrum for most common barbiturates. One adds urine to the pre-mixed reagent, incubates the solution for a few minutes at room temperature, and measures the fluorescence polarization. The tracer/antiserum reagent is stable for at least six months at 4 degrees C. Results compare favorably with two other commonly used screening techniques for barbiturates, thin-layer chromatography and the EMIT-stTM (Syva) system. Although designed as a qualitative screen, some drugs can be quantified by means of a standard curve of the relevant barbiturate.

Microbiological Turbidimetric Analysis of Low Chlortetracycline Concentrations in Feeds

1975 ◽  
Vol 58 (3) ◽  
pp. 602-608
Author(s):  
Hussein S Ragheb ◽  
Linda S Porubcan
Keyword(s):  
Bacterial Growth ◽  
Room Temperature ◽  
Cattle Feed ◽  
Standard Curve ◽  
Turbidimetric Method ◽  
Feed Supplements ◽  
Turbidimetric Assay ◽  
Swine Feed ◽  
Low Levels ◽  
Turbidimetric Analysis

Abstract Recovery studies in which chlortetracycline hydrochloride (CTC-HCl) standard was added to cattle and swine feed supplements at 4.09–9.99 g/ton showed lower antibiotic recovery turbidimetrically (80.6–98.7%) than by the AOAC modified standard as in 38.179(d) (91.2–98.7%) and the plain buffer as in 38.179(b) (93.8-133.0%) methods. Three feeds fortified with a commercial premix at the levels of 5.0 and 10.0 g CTC-HCl/ton showed an overall CTC-HCl recovery of 87.6–110.6% by manual turbidimetric assay. Results were 89.1–108.7% by the AOAC inactivated feed diluent standard and 95.4–125.4% by the plain buffer methods. For some sample extracts (as in cattle feed) the use of heat to stop bacterial growth in the turbidimetric method caused formation of a precipitate. Cooling of cultures to room temperature and rapid reading of sample turbidity followed by standard curve concentrations minimized this interference. The manual turbidimetric assay of low levels of CTC-HCl in feeds appears to offer advantages over other methods.

FURTHER STUDIES ON THE PURIFICATION OF THROMBIN

1958 ◽  
Vol 36 (1) ◽  
pp. 603-611 ◽  
Author(s):  
Walter H. Seegers ◽  
Walter G. Levine ◽  
Robert S. Shepard
Keyword(s):  
Molecular Weight ◽  
Phosphate Buffer ◽  
Esterase Activity ◽  
Room Temperature ◽  
Specific Activity ◽  
Dry Weight ◽  
The Other ◽  
Resin Column ◽  
Sedimentation Constant ◽  
Single Symmetrical Peak

Purified biothrombin (bovine) was fractionated with the use of amberlite IRC-50 columns to obtain resin thrombin with an activity of 4100 units/mg. dry weight or 45,000 units/mg. tyrosine. As obtained from a resin column in 0.3 M phosphate buffer, pH 8.0, the thrombin is stable for 5 days at room temperature. At 4 °C. about 70% of the activity remains after 20 weeks. The maximum molecular weight is estimated by comparing with the specific activity (2000 units/mg.) and molecular weight (62,700) of purified prothrombin as follows: 2000/4100 × 62,700 or 30,600 as the probable molecular weight. Resin thrombin can lose its fibrinogen-clotting power while esterase activity is retained. On the other hand the esterase activity can be depressed without diminishing the clotting activity. Resin thrombin lyses fibrin. When examined in an ultracentrifuge a single symmetrical peak was found with a sedimentation constant of S = 3.9 (20 °C., 0.1 M KCl, 5.5 mg./ml.) Citrate thrombin was also fractionated with the use of IRC-50 to obtain material with a specific activity of 47,000 units/mg. tyrosine.

Use of 3,5-dichloro-2-hydroxybenzenesulfonic acid/4-aminophenazone chromogenic system in direct enzymic assay of uric acid in serum and urine.

1980 ◽  
Vol 26 (2) ◽  
pp. 227-231 ◽  
Author(s):  
P Fossati ◽  
L Prencipe ◽  
G Berti
Keyword(s):  
Uric Acid ◽  
Sulfonic Acid ◽  
Room Temperature ◽  
Standard Curve ◽  
Analytical Recovery ◽  
Human Sera ◽  
Red Dye ◽  
Sample Measurement ◽  
Enzymic Assay ◽  
Colorimetric Procedure

Abstract A new direct colorimetric procedure for uric acid assay in serum or urine is described, utilizing a 3,5-dichloro-2-hydroxybenzene sulfonic acid/4-aminophenazone chromogenic system in the presence of horseradish peroxidase and uricase from Aspergillus flavus. This chromogen system has a high absorptivity, affording useful results with sample/reagent volume ratios as low as 0.025. The procedure is applicable to serum, plasma, or diluted urine. A single working reagent is used; the reaction is complete in less than 15 min at room temperature. The red dye formed is measured at 520 nm; a blank sample measurement is not needed. The standard curve for the method is linear for uric acid concentrations up to 1500 mumol/L. Average analytical recovery of uric acid in human sera and urine exceeded 99%; within-run and between-run precision studies showed CV's of less than or equal to 1.2 and less than or equal to 2.2%, respectively. The new procedure correlated well with the uricase/catalase and uricase/ultraviolet methods. The method is suitable for automation.

Sign in / Sign up

Export Citation Format

Share Document