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A new report discusses research on hyperaldosteronism, a condition affecting the adrenal glands. The traditional method for measuring plasma aldosterone concentration (PAC) in Japan was radioimmunoassay (RIA), but this method had limitations. To address these issues, a chemiluminescent enzyme immunoassay (CLEIA) for PAC measurement was introduced in April 2021, along with new guidelines for primary aldosteronism (PA). The study evaluated the impact of transitioning from RIA to CLEIA on PA diagnosis and found discordant diagnosis rates for certain tests. The researchers concluded that further research is needed to establish appropriate diagnostic criteria for PA. [Extracted from the article]

Researchers at the Higher National Veterinary School in Algiers, Algeria have developed and validated a solid phase radioimmunoassay system for the determination of pregnancy-associated glycoproteins (PAGs) in bovine serum. PAGs are biomarkers closely associated with pregnancy and have been shown to be effective in detecting viable embryos or pregnancy loss. The developed system demonstrated accuracy and consistency in determining PAG values in cows, and could be a valuable tool for reproductive management in dairy herds. The researchers also suggest that this diagnostic tool could be adapted for use in other livestock species. [Extracted from the article]

This essay discusses subjects related to drug use, including such topics as U.S. President Richard Nixon's campaign of a "War on Drugs," the creation of the U.S. Drug Enforcement Administration, opioid use by English poet John Keats, and drug testing known as radioimmunoassay of hair (RIAH) developed by Dr. Werner Baumgartner who founded the drug-testing company Psychemedics.

The U.S. Department of Transportation has announced that it will provide $24 million in grants to the Regional Infrastructure Accelerators (RIA) Program, which aims to expedite the development of transportation infrastructure projects at the local and regional levels. The RIA Program, funded by the USDOT, assists with project planning, development, and delivery, while also evaluating innovative financing and providing technical assistance. Two specific accelerators mentioned are the Resilient State Route (SR) 37 Program in California, which addresses congestion, flood protection, and connections to transit and rail options, and the New Mexico TradePort in Dona Ana County, which plans to build new infrastructure to support a low-carbon economy and expand trade opportunities. [Extracted from the article]

The article offers information on the testing of vitamin D for medical laboratories due to its importance to bone and mineral metabolism. Topics discussed include diseases risk associated with Vitamin D deficiency such as autoimmune diseases, type 1 and type 2 diabetes and rheumatoid arthritis; and testing for two forms of activated vitamin D. Also mentions about Chemiluminescence immunoassays (CLIA), radioimmunoassay (RIA) and binding protein assays.

The article looks into the misclassification rate of non-drug users (NDUs) in the issue of mandatory drug testing in workplaces in Canada. Topics include the article of Charles D. Feinstein titled "Deciding Whether to Test Student Athletes for Drug Use," the concept of Reasonable Cause Testing, and the Supreme Court decision on the case of Perley Day v. Irving Pup and Paper Limited. It discusses Enzyme Multiplied Immunoassay, Flourescence Polarization Immunoassay, and Radioimmunoassay.

Epidemiological data reveal that the overall risk for heart disease is lower for premenopausal women compared to age-matched men. However, the beneficial effect for the female sex is lost upon menopause. Thus, it has been suggested that estrogens convey the protective effect for the female sex against heart disease. Numerous natural plant products, i.e., phytoestrogens (PE), interfere with or alter the development or function of the endocrine system. Although PEs have been studied intensively with regard to the effects on the reproductive organs, such as the uterus or mammary gland, surprisingly little data are available about the effects of PEs on the heart. Here, we conducted a long-term study with ovariectomized mice to examine putative estrogenic effects of the PEs genistein (GEN), resveratrol (RES), and equol (EQ), using estradiol (E2) as a reference compound on heart size, morphology, and cardiac gene expression. We report for the first time significant changes in these parameters by GEN and E2. Changes in the size of cardiomyocytes were observed by GEN and E2. In line with these observations, cardiac expression of insulinlike growth factor 1 (Igf1) was significantly induced by both GEN and E2. Thus, we speculate that endocrine active compounds, like the isoflavone GEN, which is used as a food additive or as a drug for the treatment of menopausal symptoms, may directly affect heart function. [ABSTRACT FROM AUTHOR]

First devised in 1979, the scintillation proximity assay (SPA) has in recent years become an important technique in high-throughput screening for drug discovery. Characterized by speed, sensitivity, reliability and the fact that no separation step is required, the main technical limitation of SPA is the 'quenching effect'. SPA can be used in many assay formats including radioimmunoassays, ligand-receptor binding assays and enzyme assays. The SPA-based enzyme assay is usually designed in either a signal removal format (for hydrolytic enzymes), a signal addition format (for polymerases and transferases), or a product capture format (for antibodies, DNA probes, receptors or other specific binding proteins). The use of SPA in radioimmunoassays has been facilitated by new carriers such as membranes that can be configured in various shapes and sizes, allowing the assay to be performed on samples from many sources including tissue, serum or cells. The main logistical drawbacks of SPA are its cost and the need to dispose of radioactive waste. However, the technology continues to be improved, with ongoing development of cell-based assays -- eliminating the need for protein purification and avoiding protein inactivation -- non-isotopic detection systems and low-cost assays. [ABSTRACT FROM AUTHOR]

Background. Endometrial carcinoma is generally diagnosed only after the onset of postmenopausal bleeding. Although most patients with Stage I disease can be cured, the prognosis worsens significantly when the tumor is no longer confined to the uterine corpus. Serum CA 125 is elevated in only 10-20% cases of Stage I and II endometrial carcinoma. A serum tumor marker that can detect early stage endometrial cancer might aid in management of the disease. Methods. An OVX1 double-determinant radioimmunoassay was used to detect an epitope on a high-molecular-weight mucinlike glycoprotein found in the sera of 45 patients with endometrial cancer. Results. Apparently healthy persons had serum OVX1 antigen levels of 2.23 plus or minus 2.48 U/ml (mean [+ or -] standard deviation). Elevated levels of OVX1 antigen (>7.2 U/ml) were found in 5% of 184 healthy persons and in 64% of 45 patients with endometrial cancer. OVX1 antigen was elevated in 64% of 36 patients with Stage I, 50% of 2 patients with Stage II, 60% of 5 patients with Stage III, and each of 2 patients with Stage IV endometrial cancer, but only 8.6% of 58 patients with endometriosis. Elevation of serum OVX1 was found more frequently in patients with deep myometrial invasion and with poorly differentiated tumors (P < 0.01). Conclusions. The OVX1 antigen deserves further evaluation as a marker for early detection of endometrial cancers and as a prognostic factor for women with apparent early stage disease. Cancer 1994; 73:1855-8. Key words: uterine neoplasms, endometrial carcinoma, tumor markers, CA 125, mucins.

The kidneys are not only involved in the development of hypertension, but they are also often damaged if the disease is not controlled. Microalbuminuria occurs early and is easily diagnosed. However, microalbuminuria is not detected on routine Albustix testing, which has a sensitivity limit of 300 mg/L. Urinary albumin excretion, therefore, should be routinely determined by radioimmunoassay or other techniques so that appropriate therapies can be instituted to prevent nephropathy.

Monoclonal antibody (MoAb) [83D.sub.4] was generated by immunization with cell suspensions obtained from sections of formol-fixed paraffin embedded human breast cancer. It recognized an antigen expressed in breast carcinomas but not in normal breast tissue. Pleural and ascitic fluids from 66 patients were studied by an [83D.sub.4] heterologous sandwich radioimmunoassay (SRIA) using solid-phase immobilized wheat germ agglutinin to detect the [83D.sub.4] soluble antigen. Using a cutoff level of 5 units/ml of [83D.sub.4] antigen, higher values were found in 22 of 27 breast cancer-associated effusions (mean = 10.72 [+ or -] 6.80 units/ml). The 20 nonmalignant effusion fluids tested showed lower values (mean = 1.16 [+ or -] 1.49 units/ml, P < 0.001). The antigen was undetectable or present in low levels in effusions from patients with hematologic malignancies. When SRIA results were compared with conventional cytologic diagnosis in breast-cancer effusions, elevated levels of [83D.sub.4] soluble antigen were found in all patients (8 of 8) in whom malignant cells had been detected, in 4 of 8 patients with the diagnosis of 'suspected malignancy,' and in 10 of 11 patients with negative cytologic findings. Using an immunoglucosidase method on cell smears of various origins, MoAb [83D.sub.4] stained metastatic cells of breast and ovary carcinomas but did not reactive with mesothelial cells and other normal or malignant cell types. These results suggest that quantitation of the [83D.sub.4] soluble antigen may be used to improve the diagnosis of cancer in serous effusions. Cancer 1992; 69:1745-1749.

* Eighty-one normotensive and 61 hypertensive white and nonwhite subjects were studied cross-sectionally to determine the prevalence and determinants of elevated urinary albumin levels. Twenty-four-hour urinary albumin excretion was determined by radioimmunoassay. The prevalence of elevated urinary albumim level ([Mathematical Expression Omitted]) was significantly greater in hypertensive than in normotensive subjects (31.1% and 8.6%). Among hypertensive subjects, a much greater proportion of whites than nonwhites had urinary albumin levels of 15 mg/24 h or greater (39.5% and 17.4%). The independent association of blood pressure with urinary albumin level was affirmed by logistic regression analyses for white normotensive and hypertensive subjects combined, and for hypertensive subjects alone. Furthermore, among hypertensive subjects, whites were five times as likely as nonwhites to have elevated urinary albumin levels. Thus, blood pressure and ethnicity were the important determinants of urinary albumin excretion among hypertensive subjects. (Arch Intern Med. 1992;152:373-377)

A rapid, solid-phase, nonextraction progesterone kit (n = 36) was compared with an established extraction method, liquid phase tritium radioimmunoassay for progesterone (n = 79). Logistic regression of the rapid method over the extraction method gave a correlation coefficient of r = 0.968. Logistic regression gave a discriminatory zone (abnormal vs normal pregnancy) of 22.58 ng/ml by the rapid method compared with 15 ng/ml for the extraction method (log Y = 0.253 + 0.936 log X). Similar sensitivity (100% and 100%), specificity (63% and 59%), and predictive values of positive and negative tests (positive predictive value = 91% and 75%, negative predictive value = 100% and 100%) were found using a discriminatory level of 15 and 20 ng/ml for the extraction method (n = 79) and rapid method (n = 76), respectively. Clinically, curettage for patients with values less than these discriminatory zones would have given unacceptable rates for termination of a potentially normal pregnancy (38%). Clinical comparison of abnormal (ectopic or abortion) and normal (term pregnancy) outcomes in two populations of women presenting with first-trimester bleeding revealed that progesterone levels would accelerate the workup in only a small percentage (27%, 15 of 56) of patients with ectopic pregnancies. The rate of ruptured ectopic pregnancies in the observed patients was similar (20%, 3 of 15) to studies using progesterone levels prospectively. Therefore in this retrospective analysis progesterone levels would have given no greater benefit than conventional management. (Am J Obstet Gynecol 1992;1 66:562-6.)

The vascular order of pancreatic islet cellular perfusion is important in the intraislet regulation of hormone secretion. Establishment of the sequence of interaction is fundamental to understanding the physiology and pathophysiology of the human islet. Intraislet insulin from the β-cell regulates both net hormone secretion and pulsatile secretion from α- and δ-cells. In terms of vascular perfusion, the δ-cell is perfused last and does not directly affect α- or β-cells in humans. Diabetes 41:93-97, 1992, Histological studies have suggested that the human islet[1,2], like the rat islet[3,4], is composed of a core of insulin-secreting β-cells surrounded by a mantle of α- and δ-cells, which secrete [...]

The article offers information on immunoassay. Immunoassay is a biochemical test that is capable to measure and identify protein biomarkers. It has three major platforms, including enzyme-linked immunosorbent assay (ELISA) and radioimmunoassay. It has been widely used to detect, identity and quantify protein biomarkers for about two decades especially in clinical laboratories. Immunoassay is also used with increasing frequency in drug discovery.

Features Doctor Rosalyn Yalow, Nobel Prize winner for diabetes research. Academic background of Yalow; Information on Yalow's discovery of radioimmunoassay; Effect of radioimmunoassay on medical research.

The article discusses the findings of a study concerning the association between cholecystokinin in the brain and obesity in the U.S. It states that discovery was published by Nobel prize winner Rosalyn Yalow which was presented at a scientific meeting in Los Angeles, California in November 1978. It mentions that the study was conducted at the Veterans Administration Hospital using radioimmunoassay techniques.

The article focuses on the improvement of tests for early detection of prostate cancer in the U.S. Radioimmunoassay has been relied upon by researchers from the Southern California Permanente Medical Group and the University of California, Los Angeles (UCLA). The reaction in an electric field between the blood of the patient and serum from immunized rabbits to determine acid phosphatase levels has been studied by the Roswell Park Memorial Institute and Columbia-Presbyterian Medical Center.

Patients with acquired immunodeficiency syndrome (AIDS) are especially vulnerable to infection because of the reduced ability of their immune systems to fight infection. Particular infections are considered to be opportunistic in that they are more likely to cause disease under certain conditions, such as a diminished immune response. Although it normally causes symptoms in only one to five percent of infected persons, histoplasmosis is a rapidly progressive opportunistic infection in AIDS patients, causing acute pneumonia in those it affects. It spreads throughout the body and infects the liver, spleen, meninges (tissue lining the brain and spinal cord), heart, abdominal cavity and adrenal glands. Rapid diagnosis is crucial in initiating treatment in AIDS patients. Histoplasma capsulatum polysaccharide antigen (HPA) is the histoplasmosis infection which causes an immune response, normally the production of antibody to fight the infection. Detection of HPA was tested by a slightly modified radioimmunoassay procedure which uses an antigen-antibody reaction to determine the concentration of a substance. High levels of HPA were detected in the urine in almost 97 percent and in the blood of 79 percent of the AIDS patients who had disseminated histoplasmosis. When patients were treated with the antibiotic amphotericin B the levels of HPA in their urine and blood decreased significantly. In the patients who suffered a relapse of histoplasmosis the levels of HPA again increased. Detection of HPA provides a rapid method for diagnosing histoplasmosis, but further testing is required to establish the reliability of HPA levels in monitoring treatment and relapse.

The article highlights the factors that should be considered when assessing if a vitamin D assay is good for a medical laboratory and its patient population. Such factors include equimolar detection of 25-OH vitamin D3 and D2, clinical decision limits for 25-OH vitamin D, lack of harmonization among liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods and linearity or measuring range of immunoassays.

The article discusses vitamin D testing methods currently available on the market, their proposed clinical indications, platform-specific attributes and limitations. Also discussed are the procedures to ensure vitamin D tests provide clear, actionable results for patients and physicians. It highlights that CDC will introduce a Vitamin D Standardization-Certification Program to ensure reliable clinical vitamin D measurement in October 2012.

The article reports on the forecast that radioimmunoassay (RIA) will grow from 2015 to 2020 in several countries including India, Japan and China due to several factors such as the increase of medical tests performed and the increase of adoption rate of advanced techniques.

The article reports on a study by American University of Beirut researchers in Lebanon which measured the 25-hydoxyvitamin D levels of 494 adults using a radioimmunoassay and an automated chemiluminescent immunoassay, with results showing a level difference of 5 mg/mL across the two assays.

As of May 1, 2009, Pubmed listed approximately 30,000 citations on the topic of vitamin D in humans, highlighting the medical community's avid interest in this field. Two articles published in the Archives of Internal Medicine diverge with previous reports on the prevalence of hypovitaminosis D and the capability of vitamin D to reduce fractures.

Focuses on efforts to establish the kinship between sea cows, elephants and hyraxes. Long-suspected affinities between the three animals due to certain anatomical resemblances; Confirmation of the kinship through molecular comparisons; Establishment of a time scale for sirenian evolution.

Focuses on the development of Radioimmunoassay of the Hair (RIAH) procedure which is more reliable than the urine test in identifying low usage levels of drugs such as cocaine and marijuana. Lack of enthusiasm among hospitals to adopt RIAH because hospitals do not require pre-employment drug testing and they have their own toxicology labs; Benefits of RIAH.

Focuses on the diagnostic methods for the disease legionellosis. Use of biopsy specimens in making a diagnosis; Causes of the disease; Use of radioimmunoassay to identify legionellosis antigen in the urine of legionellosis victims.

Focuses on the viruses that causes gastroenteritis in humans. Symptoms of the disease; Use of radioimmunoassay to analyze outbreaks of gastroenteritis; Sources of the virus.

Reports that Fred A. Garver and his colleagues at the Medical College of Georgia in Augusta have devised a technique called radioimmunoassay to identify hemoglobin variants. Statistics on the number of hemoglobin variants identified in humans; Hemoglobin variant that causes sickle cell anaemia; Other techniques to detect hemoglobin variants; Advantages of the technique over the conventional methods.