Radioimmunoassay

Radioimmunoassay is a scientific method used to test antigens without the need to use a bioassay. It involves mixing known quantities of radioactive antigen with antibody to that antigen, then adding unlabeled or "cold" antigen and measuring the amount of labeled antigen displaced.Initially, the radioactive antigen is bound to the antibodies. When "cold" antigen is added, the two compete for antibody binding sites - at higher concentrations of "cold" antigen, more of it binds to the antibody, displacing the radioactive variant. The bound antigens are separated from the unbound ones.One method of separation used initially was the use of a second antibody directed against the first for precipitation and centrifugation. The use of charcoal suspension for precipitation was extended but replaced later by Drs. Werner and Acebedo at Columbia University for RIA of T3 and T4. An ultramicro RIA for human TSH was published in BBRC by Drs. Acebedo, Hayek et al. The free hormone stays in the supernatant, the radioactivity of which is measured and a binding curve is plotted. The technique is both extremely sensitive and specific, but it requires special precautions , sophisticated apparatus, and is expensive. The technique has been largely replaced by the ELISA method where instead of a radioactive signal, the antigen-antibody reaction is measured by colorometric signals. The RIA was developed by Rosalyn Yalow and Solomon Aaron Berson in the 1950s. Rosalyn Sussman Yalow received the 1977 Nobel Prize in Medicine for the development of the RIA for insulin. The precise measurement of minute amounts of such a hormone was a key event in endocrinology. (From the Wikpedia article Radioimmunoassay.)

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Recent Publications on Radioimmunoassay:
Inappropriately high circulating and intrarenal angiotensin II levels during dietary salt loading exacerbate hypertension in Cyp1a1-Ren-2 transgenic rats. OBJECTIVE: We evaluated the effects of salt restriction and of increasing...	21st November, 2009	aDepartment for Experimental Medicine, Institute for Clinical and	J Hypertens. 2009 Nov 18. DOI Direct Link
Ghrelin Attenuates Acute Pancreatitis-Induced Lung Injury and Inhibits Substance P Expression. OBJECTIVE:: To investigate the effect of ghrelin administration on the...	21st November, 2009	From the Surgery of Integrated Traditional and Western Medicine	Am J Med Sci. 2009 Nov 18. DOI Direct Link
[Changes of peripheral blood estradiol and testosterone in early stage after trauma.] OBJECTIV: To explore the correlation of serum estradiol, testosteron and...	20th November, 2009	Department of Emergency Medicine, Nanfang Hospital, Southern Medical	Nan Fang Yi Ke Da Xue Xue Bao. 2009 Nov 20;29(11):2262-2265.
Regulation of the cGMP-cPKG Pathway and Large Conductance Ca2+-activated K+ Channels in Uterine Arteries During the Ovine Ovarian Cycle. The follicular phase of the ovine ovarian cycle demonstrates parallel...	19th November, 2009	1University of Texas Southwestern Medical Center at Dallas.	Am J Physiol Endocrinol Metab. 2009 Nov 17. DOI Direct Link
[Effect of electroacupuncture on hippocampal NO-cGMP signaling pathway in depression rats] OBJECTIVE: To observe the effect of electroacupuncture (EA) on hippocampal...	18th November, 2009	Institute of Acu-moxibustion, China Academy of Chinese Medical Sciences,	Zhen Ci Yan Jiu. 2009 Aug;34(4):236-41.
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Press Releases About Radioimmunoassay:
Calbiotech Awarded U.S. Army Phase I SBIR Research Contract to Develop Analyte Specific Reagents for the Diagnosis of Dengue Fever Virus	6th November, 2009	Calbiotech, Inc.	SPRING VALLEY, Calif., Nov. 6 /PRNewswire/ -- Calbiotech, Inc. announced today that it has been awarded a Small Business Innovative Research (SBIR) Phase I contract by the U.S. Army Medical Research

BioNews Results for Radioimmunoassay:
Calbiotech Awarded U.S. Army Phase I SBIR Research Contract to Develop Analyte Specific Reagents for the Diagn	KOTA Territory News:  Nov 6 2009 10:13PM Matching: radioimmunoassay
Calbiotech Awarded U.S. Army Phase I SBIR Research Contract to Develop Analyte Specific Reagents for the Diagn	Montana's News Station:  Nov 6 2009 8:59PM Matching: radioimmunoassay
Calbiotech Awarded U.S. Army Phase I SBIR Research Contract to Develop Analyte Specific Reagents for the Diagn	KSLA:  Nov 6 2009 7:18PM Matching: radioimmunoassay
Calbiotech Awarded U.S. Army Phase I SBIR Research Contract to Develop Analyte Specific Reagents for the Diagn	Genetic Engineering News:  Nov 6 2009 5:23PM Matching: radioimmunoassay
Calbiotech Awarded U.S. Army Phase I SBIR Research Contract to Develop Analyte Specific Reagents for the Diagn	Freshnews.com:  Nov 6 2009 3:07PM Matching: radioimmunoassay
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Radioimmunoassay Patents:
US Patent No.	Title
7611846	Diagnostic methods involving human growth factor huXAG-1
7612178	Anti-IGF-1R antibodies and uses thereof
7612179	antibodies binding to a C-terminal fragment of apoliopoprotein E
7612181	Dual variable domain immunoglobulin and uses thereof
7612182	Anti-IL-6 antibodies, compositions, methods and uses
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Companies working in the area of Radioimmunoassay from Bioportfolio's Biocorporate database :
Company Name
Cisbio-US, Inc Cisbio International is a privately held innovative company committed to improving human healthcare with more than 50 years of experience in the fileds of therapy, medical diagnostic and drug... www.htrf-assays.com/        View full profile
MEDICORP LTD MEDICORP is Canada's largest, independent ISO 9001-certified manufacturer and distributor of immunodiagnostic and microbiology products. Included are enzyme immunoassay [ELISA], immunoradiometric ... www.medicorp.com/        View full profile

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