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Sample records for c-peptide determination radioimmunoassay

  1. Radioimmunoassay for C-peptide and proinsulin

    International Nuclear Information System (INIS)

    Heding, L.G.

    1977-01-01

    Proinsulin, the biosynthetic precursor of insulin, was discovered by Steiner et al. (1967) and shown to be converted to insulin and C-peptide in the β-cell. The first part of this paper deals with aspects of the radioimmunoassay for C-peptide with special emphasis on the development and the sources of errors encountered in our laboratory (Heding, 1975; Naithani et al., 1975). The second part deals with the many problems involved in the determination of human proinsulin and describes a direct and specific radioimmunoassay developed for measuring proinsulin in serum with a detection limit of less than 0.01 pmol/ml. (Auth.)

  2. Measurement of plasma canine C peptide by radioimmunoassay

    International Nuclear Information System (INIS)

    Besch, W.; Woltanski, K.P.; Fischer, U.; Kohnert, K.D.; Ziegler, M.

    1985-01-01

    A sensitive radioimmunoassay for canine C peptide (CCP) was established using synthetic CCP, a specific antiserum, and rabbit anti-guinea pig serum. Radioiodination was performed according to a modified chloramine T method. Tracer preparations have been used for 6 weeks after iodination. The standard curve ranges from 0.028 to 3.0 nmol/l. The intra-assay coefficient of variation (CV) was 3-5% and the inter-assay CV was 6-9% in the optimal range between 0.3 and 0.8 nmol/l. The average recovery of CCP added to plasma samples was 100.6% (n = 9). Canine insulin, porcine proinsulin, bovine proinsulin, and human C peptide exhibited no cross-reactivity. The mean fasting plasma CCP concentration was 0.089 +- 0.021 nmol/l in normal dogs and -0.005 +- 0.007 nmol/l (mean +- SEM) in diabetic dogs, respectively. (author)

  3. Insulin and C-peptide in human brain neurons (insulin/C-peptide/brain peptides/immunohistochemistry/radioimmunoassay)

    International Nuclear Information System (INIS)

    Dorn, A.; Bernstein, H.G.; Rinne, A.; Hahn, H.J.; Ziegler, M.

    1983-01-01

    The regional distribution and cellular localization of insulin and C-peptide immunoreactivities were studied in human cadaver brains using the indirect immunofluorescence method, the peroxidase-antiperoxidase technique, and radioimmunoassay. Products of the immune reactions to both polypeptides were observed in most nerve cells in all areas of the brain examined. Immunostaining was mainly restricted to the cell soma and proximal dendrites. Radioimmunoassay revealed that human brain contains insulin and C-peptide in concentrations much higher than the blood, the highest being in the hypothalamus. These findings support the hypothesis that the 'brain insulin' is - at least in part - produced in the CNS. (author)

  4. A study on the C-peptide radioimmunoassay with synthetized connecting peptide

    International Nuclear Information System (INIS)

    Nakagawa, Shoichi; Sasaki, Takashi; Nakayama, Hidetaka; Watanabe, Takuji; Aoki, Shin

    1976-01-01

    A method of C-peptide radioimmunoassay with the synthetized connecting peptide by Yanaihara was tested for the determination of serum C-peptide immunoreactivity (CPR) in normal people and in diabetics with or without insulin treatment. The CPR value obtained by this method was not interfered with by the presence of serum proteins or by the insulin of people with or without insulin treatment judged by the dilution test and the recovery test. The normal fasting CPR was 2.80 +- 0.78 ng/ml with the synthetized C-peptide as a standard. The CPR value increased and reached a maximum 90 minutes after the ingestion of 50 g of glucose. The increase after the glucose loading reduced corresponding to the severity of diabetes, and some juvenile-onset diabetes showed no response. Adult-type diabetics under insulin treatment, however, showed weak but significant CPR response. The increment of CPR and immunoreactive insulin after glucose loading in normal people and non-treated diabetics was well correlated (γ=0.8262). Judged from the above mentioned results, CPR determination in insulin-treated diabetics was thought to be a useful method for the assessment of the insulin-secreting ability of beta-cells of the pancreas. (J.P.N.)

  5. C-peptide comparative radioimmunoassays: a study of three commercial kits

    International Nuclear Information System (INIS)

    Villaume, C.; Beck, B.

    1983-01-01

    Plasma C-peptide immunoreactivity (CPR) was measured in 18 fasting subjects with three different commercial kits (RIA-mat C-peptide-, Byk-Mallinckrodt; RIA-gnost-hC-peptide, Hoechst-Behring; human C-peptide radioimmunoassay kit, Novo) The subjects were chosen as to cover a wide range of CPR concentrations (five healthy subjects, six obese subjects, three insulin-dependent diabetics, four normal subjects whose plasmas had been kept at - 20 0 C for periods of 16 or 36 months). CPR was measured with the Novo kit in eight other plasmas which were kept over a period of 36 months, with or without aprotinin. Good correlations have been established among the values found with the three kits. However, absolute concentration values for each subject as well as the dispersion of all plasma C-peptide values varied as a function of the kit used because of antibody specificity differences and because of the various separation methods. The normal range proposed changes with each kit and the blood CPR of a subject can be a normal, reduced or increased one, depending on the kit used. After several months of storage, plasma CPR degradation is observed with the three kits. A protease-inhibitor is necessary in order to avoid this C-peptide degradation due to the apparent existence of a plasma proteolytic enzyme

  6. Fundamental studies on the development of C-peptide radioimmunoassay kit

    International Nuclear Information System (INIS)

    Nakazawa, Nobuhiko; Maki, Kentaro; Ogawa, Hiroshi; Ikeda, Osamu

    1976-01-01

    We have studied the development of the C-peptide radioimmunoassay kit which is usable in the pancreatic function test with satisfactory results. The C-peptide antiserum was prepared by immunizing rabbits with synthetic human connecting peptide. The antiserum revealed no cross reaction with any C-peptides other than human C-peptide, porcine insulin and gastrointestinal hormone, and showed high specificity to human C-peptide. We adopted the double antibody method in B,F separation, and chose 4 0 C, 48 hrs. for 1st. incubation and 4 0 C, 24 hrs. for 2nd. incubation. On this kit, the assay range was 0.5 ng/ml-30 ng/ml, the recovery rate was 98.4%-107.8% in the recovery test, the coefficient of variance was 6.2% in the intra assay and was 7.6% in the inter assay. We think this kit is sufficiently usable to assay C-peptide in blood. (auth.)

  7. Determination of serum IgD radioimmunoassay

    International Nuclear Information System (INIS)

    Fayol, V.; Hartmann, D.J.; Sabbagh, I.; Ville, G.

    1986-01-01

    We describe a sensitive liquid phase radioimmunoassay for serum IgD. Extreme values obtained from 85 control patients sera are 0.2 and 121 mg/l with an arithmetic mean of 25 mg/l. In atopic patients (with high serum IgE levels), arithmetic mean is 47 mg/l [fr

  8. Determination of serum IgD radioimmunoassay

    Energy Technology Data Exchange (ETDEWEB)

    Fayol, V.; Hartmann, D.J.; Sabbagh, I.; Ville, G.

    1986-01-01

    We describe a sensitive liquid phase radioimmunoassay for serum IgD. Extreme values obtained from 85 control patients sera are 0.2 and 121 mg/l with an arithmetic mean of 25 mg/l. In atopic patients (with high serum IgE levels), arithmetic mean is 47 mg/l.

  9. The determination of serum prolactin by radioimmunoassay

    International Nuclear Information System (INIS)

    Tantirasdr, K.

    1980-01-01

    The iodination of hPRL with 125 I utilizing chloramine-T technique at temperature 4 degrees C gave 125 I-hPRL having immunoreactivity. 125 I-hPRL could be used as a labelled compound for determination of human prolactin by radioimmunoassay. The assay was performed using 125 I-hPRL 5,000 cpm/tube and anti-hPRL 1 : 400,000 dilution (final) incubated at 25 degrees C for 24 hr. One percent dextran-coated charcoal suspension (0.5 ml) was used for separation of free from bound form. The criteria of reliability of the method was evaluated in terms of accuracy, precision, specificity and sensitivity. Under the condition of the assay, the addition of known amount of hPRL (6-50 ng/ml) to charcoaled serum, the recovery of the added hPRL was found to be 97.3-120.8%. The within and between assay variation were evaluated from replicate measurements of the same samples in the same assay and in three different assays. The percentage coefficients of variation was found to be 7.7-15.8% and 13.1-24.0% for within and between assays respectively. Cross-reactivities of tested several protein hormones indicated that the anti-hPRL was very specific. The sensitivity was found to be 1.90 ng/ml. The method was applied to measure serum prolactin for one cycle of 4 volunteers Thai women having normal menstrual cycle. The mean ± S D of serum prolactin was found to be 15.9 ± 5.6, 21.2 ± 12.7 and 16.4 ± 6.2 ng/ml at follicular phase, mid-cycle and luteal phase respectively

  10. Determination of carbofuran in water by radioimmunoassay

    International Nuclear Information System (INIS)

    Zhu Guonian; Wu Huiming; Yang Ting; Hu Xiuqing

    2004-01-01

    A competitive radioimmunoassay (RIA) method was established to detect carbofuran in water samples. Compared with traditional analytical methods RIA provided a easy procedure with higher sensitivity. The detective limitation of RIA for carbofuran was proved to be 0.175 ng/ml. A study was performed to test validation of the RIA. In this study carbofuran residues in water samples were detected simultaneously by RIA and by high performance liquid chromatograph (HPLC). The linear correlation coefficient of the test results was measure to be 0.9985. (authors)

  11. Determination of plasma oxytocin by radioimmunoassay

    International Nuclear Information System (INIS)

    Ogawa, Satsuki; Fukuchi, Soitsu; Miura, Tadashi

    1978-01-01

    A simple radioimmunoassay was applied to the measurement of oxytocin in human plasma. A high specificity of immunoassay was demonstrated by the fact that large excess of angiotensin I and II, and ACTH did not displace labelled oxytocin from the antibody. Lysine-8-vasopressin and arginine-8-vasopressin showed very little cross-reaction in the assay, possessing only 0.002% of the immunological potency of oxytocin. The specific activity of 125 I-oxytocin was 166 μCi/μg. Adsorption and extraction capacities of Florisil were 96.6 +- 2.1% and 85.7 +- 2.5%, respectively. Intra- and inter-assay variability were 7.2 +- 4.9% and 4.3 +- 2.2%, respectively. The sensitivity of the assay was below 1 pg/tube. Normal levels of plasma oxytocin were 0 - 2.2 pg/ml (n=13) in males and 0 - 10.4 pg/ml (n=10) in females. Plasma oxytocin levels in the 39th and 40th weeks of pregnancy were 27.9 +- 4.14 pg/ml (n=4) and 29.8 +- 17.1 pg/ml (n=13), respectively. The levels increased to 33.1 +- 12.1 pg/ml (n=7) and 37.1 +- 17.5 pg/ml (n=7) in the first and third stages of labor, and decreased to 13.6 +- 5.25 pg/ml (n=6) on the 2nd to 8th day after labor. The radioimmunoassay for oxytocin in plasma is considered to be sufficiently applicable for clinical use. (auth.)

  12. Determination of triiodothyronine in serum by enzyme- and radioimmunoassay

    International Nuclear Information System (INIS)

    Oellerich, M.; Haindl, H.; Medizinische Hochschule Hannover

    1981-01-01

    An evaluation of a heterogeneous enzyme immunoassay for determination of triiodothyronine in serum (Enzymun-Test T 3 , Boehringer Mannheim) is presented. The enzyme immunoassay was compared with the laboratory routine radioimmunoassay. The precision of both assays was satisfactory at triiodothyronine concentrations between 1.0 and 8.0 nmol/l (coefficients of variation from day to day 3 from 96-104% and with the radioimmunoassay from 88-111%. A comparison of the results obtained by Enzymun-Test T 3 and the radioimmunoassay in a series of 103 patients showed a good correlation between both methods. L-thyroxine did not cause a relevant cross-reaction in the enzyme immunoassay. About 20 unknown samples can be analyzed in triplicate by Enzymun-Test T 3 within 260 minutes. (orig.) [de

  13. Radioimmunoassay for determination of the hormonal and immune states in patients aczema; psoriasis and neurodermatitis

    International Nuclear Information System (INIS)

    Baltabaev, T.S.

    1989-01-01

    The hormonal and immune status was investigated by a radioimmunoassay in 105 patiets with dermatosis (55 female and 50 male patients aged 15 to 80): 51 suffered frm ecsema, 41 -from psoriasis, and 13 - from neurodermatitis. Serum concentrations of T 3 , T 4 , TSH, insulin, trypsin, C-peptide, cortisol, and IgE were investigated. Disorders of the hormonal and immune status were noted in the examinees with relation to sez, type of disease, season, time-period and extent of disease

  14. Radioimmunoassay for determination of thyroglobulin in human serum

    International Nuclear Information System (INIS)

    Rodriguez Cabrera, M.E.; Blanca Fernandez, S.; Baldor Navarro, F.; Rodriguez Gonzalez, J.C.

    1996-01-01

    We described the development and analytical evaluation of a radioimmunoassay with double antibody in liquid phase for human serum thyroglobulin determination using a set of reagents produced in the National Institute of Endocrinology. The reference interval for normal population was 5.7 - 44 ng/ml (X± 2DS; n=170). The intra-assay precipision was 8.1 % (control serum A) and 7.0 (control serum B) and the inter-assay precision was 9.1 % (control serum A) and 9.2 % (control serum B). The sensibility was 4.7 ng/ml and the recovery was 95 %

  15. Pancreatic elastase in human serum. Determination by radioimmunoassay

    Energy Technology Data Exchange (ETDEWEB)

    Geokas, M.C. (Univ. of California, Davis); Brodrick, J.W.; Johnson, J.H.; Largman, C.

    1977-01-10

    This study demonstrates that a serine endopeptidase of pancreatic origin (elastase 2) circulates in human blood. A specific and highly sensitive radioimmunoassay has been developed for pancreatic elastase 2 in human serum. The inactivation of elastase 2 employed as radioiodinated tracer with an active site-specific reagent (phenylmethanesulfonyl fluoride) was necessary to prevent its binding by serum ..cap alpha../sub 1/-antitrypsin and ..cap alpha../sub 2/-macroglobulin while maintaining its immunoreactivity. The assay is based upon competition of standard human pancreatic elastase 2 with /sup 125/I-labeled phenylmethanesulfonyl elastase 2 for specific antibody binding sites, after which a second antibody precipitation step is used to separate bound from free /sup 125/I-labeled phenylmethanesulfonyl elastase 2. The minimum detectable concentration of elastase 2 was 0.9 ng/ml. The average normal fasting serum level determined was 71 ng/ml, approximately 80-fold greater than the minimum detectable amount.

  16. Comparative studies on the determination of alphafetoprotein by enzyme immunoassay and by radioimmunoassay

    International Nuclear Information System (INIS)

    Haller, G.; Linneke, P.; Voss, P.; Jeske, W.

    1987-01-01

    Alphafetoprotein (AFP) was determined in serum of pregnant women in the tenth till sixteenth week of pregnancy by means of two enzyme immunoassays (Enzymun-Test AFP, Boehringer Mannheim, FRG and AFP EIA 'Dessau' 1000, Research Institute for Vaccine Dessau, GDR) and a radioimmunoassay (Radioimmunoassay Kit, AFP-PR, CIS, France). Parallel determinations in sera of 438 patients, who had come to surveillance for the first consultation were estimated. A comparison between the methods showed a good correlation. (author)

  17. Insulin C-peptide test

    Science.gov (United States)

    C-peptide ... the test depends on the reason for the C-peptide measurement. Ask your health care provider if ... C-peptide is measured to tell the difference between insulin the body produces and insulin someone injects ...

  18. Automatic computation of radioimmunoassay data

    International Nuclear Information System (INIS)

    Toyota, Takayoshi; Kudo, Mikihiko; Abe, Kanji; Kawamata, Fumiaki; Uehata, Shigeru.

    1975-01-01

    Radioimmunoassay provided dose response curves which showed linearity by the use of logistic transformation (Rodbard). This transformation which was applicable to radioimmunoassay should be useful for the computer processing of insulin and C-peptide assay. In the present studies, standard curves were analysed by testing the fit of analytic functions to radioimmunoassay of insulin and C-peptides. A program for use in combination with the double antibody technique was made by Dr. Kawamata. This approach was evidenced to be useful in order to allow automatic computation of data derived from the double antibody assays of insulin and C-peptides. Automatic corrected calculations of radioimmunoassay data of insulin was found to be satisfactory. (auth.)

  19. Radioimmunoassay for determination of tumor markers in the diagnosis of rectal cancer recurrences

    International Nuclear Information System (INIS)

    Ozhiganov, E.L.; Kuznetsova, L.F.

    1991-01-01

    The levels of tumor markers were determined in patients with rectal cancer recurrences by radioimmunoassay. An increase in a CEA level was observed most frequently. An increase in the levels of α-fetoprotein, ferritin and β 2 -microglobulin was observed. It was shown that the most specific and effective diagnostic test of rectal cancer recurrences was the determination of a CEA level

  20. Radioimmunoassay of hair for determining opiate-abuse histories

    International Nuclear Information System (INIS)

    Baumgartner, A.M.; Jones, P.F.; Baumgartner, W.A.; Black, C.T.

    1979-01-01

    Heroin and morphine metabolites can be detected in hair with the use of commerically available radioimmunoassay reagents and with minor sample preparation. Hair samples obtained from morphine-treated mice and heroin users contained nanogram levels of the drug per milligram of hair (single human hair). The results of the hair analyses for all subjects admitting the use of heroin were positive, whereas the results of only 30% of thin-layer chromatographic urinanalyses of these same subjects were positive. In addition, differences in drug concentration for sections of hair near the scalp and near the distal end correlated with the length of time the drug had been used. These results exemplify the potential advantages of the use of hair analysis over urine and serum analyses in terms of accessibility, sample stability, and long-term retention of information

  1. Radioimmunoassay determination of antigenic concordance among hemagglutinins of vaccine and epidemic influenza virus strains

    Energy Technology Data Exchange (ETDEWEB)

    Blokha, V.V.; Yamnikova, S.S.; Karpovich, L.G.; Yakhno, M.A.; Zakstel' skaya, L.Ya.

    Radioimmunoassay studies were conducted on the antigenic concordance of hemagglutinin of influenza A H3N2 viruses, to determine the suitability of vaccine strains in engendering immunity against viruses circulating in nature. Specifically, the inhibition studies involved the hemagglutinins of the A/Victoria/35/72 vaccine strain, the proposed vaccine strain A/Khabarovsk/15/76, and the RK-5 recombinant strains, containing antigenic determinants of viruses isolated in the 1972-1976 epidemic period (A/Victoria/3/75, A/Leningrad/173/75, A/Victoria/112/76). The results showed that A/Victoria/35/72 is becoming less important as a vaccine, but that RK-5 and A/Khabarovsk/15/76 can provide significant immunity with respect to influenza viruses circulating in 1975-1976. These observations point to the usefulness of radioimmunoassay in assessing the suitability of influenza A viruses for vaccine production. 12 references, 2 figures.

  2. Ovulation following gonadotrophin treatment and determination of serum estradiol and progesterone by radioimmunoassay

    International Nuclear Information System (INIS)

    Vesper, B.; Lisse, K.; Ittrich, G.

    1979-01-01

    The use of gonadotrophins to release ovulation is indicated in women with urgent desire for children and with negative response to clomiphene therapy. 69 patients treated with 100 therapeutic gonadotrophin series were examined. Estrogens and progesterone were determined by radioimmunoassay. The treatment resulted in ovulation in 54 women, 12 patients developed an ovarian reaction with an increase of estrogen, and in 34 cases no ovarian response was detectable. 6 women became pregnant during gonadotrophin therapy and further 2 after treatment

  3. Free light chains of immunoglobulins in normal serum and urine determined by radioimmunoassay

    International Nuclear Information System (INIS)

    Soelling, K.

    1975-01-01

    A radioimmunoassay for determination of free light polypeptide chains from human immunoglobulins in serum and urine is described. The free light chains were isolated from the regular immunoglobulins by gel filtration on Sephadex G-100 columns. In the radioimmunoassay the free and antibody-bound 125 I-labelled light chains were separated by gel filtration through Sephadex G-200 columns. The mean concentration of free light chains in serum from 20 normal subjects was 10.6 mg/l for lambda chains and 13.2 mg/l for kappa chains. The 24-hr urinary excretion was 1.1mg for lambda chains and 3.2 mg for kappa chains. (auth)

  4. Radioimmunoassay methods for the determination of L-triiodo-thyronine and thyroxine

    International Nuclear Information System (INIS)

    1976-01-01

    An improved, simplified radioimmunoassay method for the in vitro determination of L-triiodo-thyronine in unextracted blood serum is described which involves the use of a combination reagent constituted by a buffered solution containing radioactive L-triiodothyronine and an inhibitor for inhibiting the binding of L-triiodothyronine to thyroxine-binding globulin. Optionally the reagent may also include an antiserum containing an antibody capable of immunoreactivity with L-triiodothyronine. Packaged test kits for use in conveniently carrying out the radioimmunoassay are also provided. Certain salts of 8-anilino-1-naphtalene sulfonic acid, which may be regarded as purified forms of the acid, are preferably employed as inhibitors for inhibiting binding of L-triiodothyronine to thyroxine-binding globulin

  5. Determination of degree of oncologic disease spreading with the use of radioimmunoassay

    International Nuclear Information System (INIS)

    Chebotareva, Eh.D.; Shishkina, V.V.; Korolev, V.I.; Sklyar, S.Yu.; Kukot', V.A.

    1989-01-01

    An effort to evaluate the possibility of applying tumor morkers to determine the degree of oncologic desease propagation is made. Radioimmunoassay of 431 patients with tumors with different localization is performed. In patients with lung, esophagus, stomach, rectum cancer the level of carcinoembryonic antigen (CEA) in the blood serum is studied, with mammary gland cancer - the CEA, ferritin and prolactin levels. An increase of CEA level is detected under wide-spread forms of lung, esophagus, stomach and rectum cancer, and an increase of CEA, ferritin and prolactin levels-under mammary gland cancer. It is shown that radioimmunoassay of tumor marker level is quite information content as to the evaluation of tumor process propagation under digestive tract, lung and mammary gland cancer. 12 refs.; 5 tabs

  6. Radioimmunoassay to determine thyroglobulin concentration in the human blood serum

    International Nuclear Information System (INIS)

    Shcherban', A.I.; Shol'kina, L.V.; Ivanov, P.K.; Chinareva, I.V.; Piven', N.V.; Bogdanovich, A.F.; Guzov, V.M.

    1986-01-01

    An assay for determining thyroglobulin (TG) concentration in human blood serum has been developed. TG content in patients with thyroid cancer was determined before and after operation. Good correlation of TG level with prevalence of tumoral process is noted. This system meets the requirements of WHO to radioimmune assays and can be used in medical practice

  7. Radioimmunoassay method for the determination of cardiotonic glycosides

    International Nuclear Information System (INIS)

    1975-01-01

    A kit method for the in vitro determination of digoxin and digitoxin is described. The blood serum is mixed with the reagent which consists of an aqueous buffer solution containing a radiolabeled hapten for the glycoside. Antiserum with specific antibodies is added and the mixture is incubated. Thereafter, a thin strip of membrane mainly consisting of an ionexchanger is brought into contact with the mixture to separate the antibody bound hapten from the unbound hapten. The ratios of both are determined by counting the radioactive hapten

  8. Results of the HPL determination using a new enzymatic immunoassay - comparison with a commercial radioimmunoassay

    International Nuclear Information System (INIS)

    Leis, D.; Schneider, B.; Keller, A.; Braun, S.

    1982-01-01

    An enzymatic immunoassay recently developed by the firm Organon, Oss, Netherlands, to determine HPL in the serum of pregnant women was compared to a widely used radioimmunoassay marketed by the firm Amersham-Buchler, Braunschweig. The values determined showed a good correlation. The accuracy of measurement was within the generally accepted range for immunological assays of this kind. The assay procedures are comparable with regard to the expenditure of time and work. A great advantage of the EIA is due to the absence of radioactive substances, which permits this test to be performed in any laboratory equipped with a centrifuge and photometer. (orig.) [de

  9. Prenatal sex determination by radioimmunoassay of testosterone with and without chromatography of the amniotic fluid

    International Nuclear Information System (INIS)

    Distler, W.; Boniver-Ollmann, U.; Tigges, J.; Terinde, R.; Claussen, U.

    1979-01-01

    Amniotic fluid testosterone measured by radioimmunoassay (RIA) without chromatography (immunoreactive testosterone) seems not to be a definitive test for prenatal sex determination in all cases. In this study testosterone (T) levels measured by RIA with chromatography of the amniotic fluid samples were compared with immunoreactive testosterone (iT) values, to determine the predictive accuracy of the two methods. In 111 amniotic fluid samples between 15 and 19 weeks of gestation iT and T were measured parallelly. There are significant differences between iT- and T-means of both sexes (p [de

  10. Standardization of the radioimmunoassay technique for the determination of human gastrin and its clinical application

    International Nuclear Information System (INIS)

    Peig Ginabredra, M.G.

    1989-01-01

    It was developed and standardized a system of radioimmunoassay for the determination of gastrin, employing synthetic human gastrin for radioiodination and preparation of standard as well as specific antibody raised rabbits. The hormone was labeled with 125 I by the Cloramine T techique and purified by anion exchange chromatography in QAE-Sephadex A-25, being determined its specific activity. The tracer thus obtained was submitted to analysis of purity by poliacrilamide gel eletrophoresis and precipitation of proteins by trichloroacetic acid. Its stability evaluated according to the time of storage, being its purity and adequation for the use in radioimmunoassay also compared to a tracer obtained from a commercial diagnosis kit. The assays were performed by incubation of radioiodinated gastrin, standard gastrin prepared in plasma free from this hormone (from zero to 500 pmol/l) or samples to be assayed with the antiserum for 4 days at 4 0 C. The separation between the free gastrin and the gastrin bound to the antibody was carried out by adsorption of the free hormone to the charcoal, whose ideal concentration was previously determined. Plasma free from gastrin was obtained from time-expired blood bank plasma submitted to extraction with charcoal. When performed the quality control, this radioimmunoassay was shown specific, accurate, precise and sensitive, allowing the performance of valid assays. Its validation was even confirmed by clear discrimination not only of the gastrin concentration in subjects with very low levels (gastrectomized) and extremely high levels (Zollinger-Ellison syndrome) as well as gastrin concentrations in subjects with other diseases, such as Chagas disease, pernicious anemia and chronic renal failure. (author) [pt

  11. Use of radioimmunoassay procedures for the determination of sex hormones in animal tissues

    International Nuclear Information System (INIS)

    Hoffmann, B.

    1983-01-01

    Radioimmunoassay methods for the determination of sex steroids and other compounds with sex hormone-like activities in various edible animal tissues and endocrine glands have been developed. Reliability of these methods, allowing quantification in a range of 10 -11 M, has been adequately demonstrated. When applied to monitoring residues of anabolic sex hormones in edible tissues of veal calves, physiological baseline levels of some endogenous ''anabolic'' steroids (like testosterone, oestrogens) were established; in the case of xenobiotics residues at the scheduled time of slaughter could be quantified (trenbolone) and a regulatory method to implement the ban of diethylstilbestrol was introduced. (author)

  12. Use of radioimmunoassay procedures for the determination of sex hormones in animal tissues

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, B. (Institut fuer Veterinaermedizin des Bundesgesundheitsamtes (Robert von Ostertag-Institut), Berlin (Germany, F.R.))

    1983-07-01

    Radioimmunoassay methods for the determination of sex steroids and other compounds with sex hormone-like activities in various edible animal tissues and endocrine glands have been developed. Reliability of these methods, allowing quantification in a range of 10/sup -11/ M, has been adequately demonstrated. When applied to monitoring residues of anabolic sex hormones in edible tissues of veal calves, physiological baseline levels of some endogenous ''anabolic'' steroids (like testosterone, oestrogens) were established; in the case of xenobiotics residues at the scheduled time of slaughter could be quantified (trenbolone) and a regulatory method to implement the ban of diethylstilbestrol was introduced.

  13. Development of a radioimmunoassay for the determination of buprenorphine in biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Debrabandere, L.; Boven, M. Van; Daenens, P. (Louvain Univ. (Belgium))

    1993-02-01

    The development of a specific and sensitive radioimmunoassay for the detection of buprenorphine in urine samples is described. With minor adjustments, the assay was also applied to the analysis for buprenorphine in plasma samples. The 2-diazobenzoic acid derivative of buprenorphine has been prepared as a hapten. The immunization of rabbits with the hapten-bovine serum albumin conjugate resulted in the production of antibodies, which cross-reacted with N-dealkylbuprenophine up to about the 90% level. The antibodies showed very low cross-reactivities with the 3-O-glucuronides and with the structural analogue etorphine. The assay was mainly used to prescreen for buprenorphine in urine samples of persons suspected of Temgesic misuse and to determine buprenorphine in plasma samples. A linear calibration graph for buprenorphine was obtained after logit-log regression. The spiking recovery study showed a linear regression. Intra-and inter-assay relative standard deviations were < 4.35 and < 6.36%, respectively. A comparison study of the high-performance liquid chromatographic determination (X) to the radioimmunoassay (Y) resulted in the following regression equation for the urine samples: Y = 1.44 + 1.64 X (n = 32; r 0.910) and Y = 0.007 + 1.58 X (n = 10; r = 0.930) for plasma specimens. The minimum detectable dose of the immunoassay was calculated to be 10 pg ml[sup -1] (Student's t-distribution, p 0.01, degrees of freedom = 8). (Author).

  14. Radioimmunoassay determination of urinary prostaglandins in patients with progressive systemic sclerosis

    International Nuclear Information System (INIS)

    Ramirez P, P.; Erbessd, M.L.; Mares, G.; Recinos, G.; Graef S, A.; Lavalle, C.

    1985-01-01

    The results of urinary determinations of E-2 prostaglandines by radioimmunoassay (RIA) in 24-hour urine are presented for three groups: progressive systemic sclerotic patients with normotension and with elevated or normal APR, progressive systemic sclerotic patients with hypertension and with normal or low APR, control group of normal subjects. In a recent report of progressive systemic sclerosis in patients we demonstrated changes in the urine concentratrion of APR levels, sodium excretion and in total blood volume. Based on these findings we felt the need to perform quantifications of E-2 prostaglandines (PGE-2) in 24-hour recently taken urine samples stored at 70 0 and measure the sodium amounts excreted in the urine. We concluded that urinary determination of E-2 prostaglandines was the most suitable for our study as it allowed the establishment of relationships between APR, aldosterone and metabolic sodium balance. (author)

  15. C-Peptide Test

    Science.gov (United States)

    ... Syndrome Staph Infections and MRSA Stroke Testicular Cancer Thalassemia Thyroid Cancer Thyroid ... Get Tested? To help evaluate insulin production by the beta cells in the pancreas or to help determine ...

  16. Importance of radioimmunoassay for the determination of tumor markers in the diagnosis of malignant lymphomas

    International Nuclear Information System (INIS)

    Purizhanskij, I.I.; Pavlichuk, S.N.; Toritsina, L.K.

    1989-01-01

    The investigation was conducted to study the role of the determination of tumor markers (CEA, β 2 -microglobulin, IgE and ferritin) in patients with malignant lymphomas. Altogether 66 patients with Hodgkin's disease, 60 with non-Hodgkin's lymphomas and 15 with clinocohematological remission over one year were investigated, using radioimmunoassay with commercial kits of reagents. An increase in the level of β 2 -MG was shown to depend on the spreading of a lymphoproliferative process. An elevated level of IgE was noted in Hodgkin's disease whereas a significant rise was unnoticed in non-Hodgkin's lymphomas. An increase in the level of serum ferritin was noted in an advanced and aggressive lymphoproliferative process. The CEA test in malignant lymphomas is not informative

  17. Evaluation of extraction methods for progesterone determination in rabbit (Oryctolagus cuniculus) feces by radioimmunoassay

    Energy Technology Data Exchange (ETDEWEB)

    Korndoerfer, Clotilde Maria; Meirelles, Cyro Ferreira; Bueno, Ives Claudio da Silva; Abdalla, Adibe Luiz [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil). Secao de Ciencias Animais]. E-mail: cfmeirel@esalq.usp.br

    1998-07-01

    The purpose of this study was to find a practical procedure for the extraction of progesterone (P{sub 4}) from feces and to determine if the P4 plasma profiles during pregnancy were reflected in total fecal P4 of pregnant rabbits. The rabbit was used as model for the techniques. Plasma and feces were collected from 11 rabbits during a period of 42 days. Three different methods of P4 extraction were used. The total P4 was measured by solid-phase radioimmunoassay (RIA) with {sup 125} I-P4 as the tracer. Results suggested that it was possible to extract total P4 from rabbit feces with methanol and petroleum ether. Plasma and fecal P4 profiles were compared for both pregnant and ovariectomized rabbits. It was possible to differentiate total P4 extracted from day two through 28 after breeding (p<0.01). (author)

  18. Comparative determination of the rheumatic factor by means of agglutination, immunofluorescence and radioimmunoassay

    International Nuclear Information System (INIS)

    Jaeger, L.; Storz, H.; Hein, G.; Schlenvoigt, G.

    1982-01-01

    The rheumatic factor (RF) was determined by means of agglutination, immunofluorescence (IF) test and radioimmunoassay (RIPEGA) in random groups of 56 patients with rheumatoid arthritis (RA), 13 patients with seronegative RA and 39 patients with psoriasis arthropathica. All three methods are of equal value with regard to the number of positive results. Further classification of seronegative patients, i.e. patients with a negative agglutination reaction and the clinical symptoms of RA is possible with the IF method and, above all, by means of RIPEGA. But because of the comprehensive test devices the two methods are only an alternative. Titer differences are attributed to the different indication principles and the immunological heterogeneity of RF. An improvement of the diagnosis of activity was not possible. (author)

  19. Connecting peptide (c-peptide) and the duration of diabetes mellitus ...

    African Journals Online (AJOL)

    Objective: C-peptide is derived from proinsulin and it is secreted in equimolar concentration with insulin. Plasma C-peptide is more stable than insulin and it provides an indirect measure of insulin secretory reserve and beta cell function. To determine relationship between C-peptide and duration of diabetes mellitus, age, ...

  20. Somatomedin A in human serum: determined by radioimmunoassay and radioreceptorassay; results and implications

    International Nuclear Information System (INIS)

    Hall, K.; Sara, V.

    1981-01-01

    The polypeptide hormones in the somatomedin family were discovered as three different biological activities of serum: insulin-like activity (ILA), sulphation factor activity (SFA) and multiplication stimulatory activity (MSA). Three different biological actions on three different target tissues have been used to identify the somatomedins during their purification. All the somatomedins contain ILA, SFA and MSA but their order of potency of biological action varies from tissue to tissue. It is apparent that the pattern of somatomedin levels determined throughout human life varies according to the technique used for their determination. Each assay has a unqiue order of crossreaction for the various somatomedins, and is sensitive to different forms present in blood. Thus the different patterns must reflect the predominance of specific somatomedins at certain stages of life. The heterogeneity of polypeptide hormones in the circulating blood is well recognized but its relation to age and development has yet to be fully explored. Methods for the estimation of the somatomedins must take account of such differences. In the radioimmunoassay field it is generally recognized that each type of antibody has a unique recognition pattern. This applies equally to the radioreceptorassay where the specificity of the receptor varies according to species, organ and age. Consequently, it is essential that age-related standards are established for each technique for the determination of somatomedins. (Auth.)

  1. Applications of a solid phase radioimmunoassay (SPRIA) to the micro-determination of ABO blood group

    International Nuclear Information System (INIS)

    Wu Fenqiang; Guo Jingyuan

    1995-01-01

    The authors report a simple, rapid, sensitive and accurate solid phase radioimmunoassay (SPRIA) method which has been improved. The research included the tests of its methodological parameters, sensitivity, accuracy, and the studies on its applications to the detection of blood group substances in varied forensic biological materials. The coefficient variation of intra-assay was 5.6%, and that of inter-assay was 10.15%. As to its applications to the forensic serology, the ABO blood groups of human bloodstain, hair follicular tissues and salivary stains had been tested and the results were satisfying. Later, 50 unknown type bloodly samples had been blind tested. The judging level used to identify the positive and negative wells was 800 cpm, that meant, if the radioactive count of a well were over 800 cpm, it was determined as a positive well, if that of a well were below 800 cpm, it was negative well. As SPRIA is a method of micro-determination which can micro-test the blood group antigens contained in varied forensic biological materials, it should has a good future of its applications to the forensic medicine fields

  2. Radioimmunoassay method of androgen determination (testosterone and dihydrotestosterone) in human male blood serum without extraction and chromatography

    International Nuclear Information System (INIS)

    Budziszewska, B.; Rembiesa, R.

    1983-01-01

    A radioimmunoassay method for androgen determination (testosterone and dihydrotestosterone) in blood serum, without extraction and chromatography, has been described. Antibodies obtained by immunization of animals with testosterone-3-carboxymethyl oxime coupled to bovine serum albumin were used. The antibody obtained was homogenous and specific, with the association constant of 5.71 X 10 9 l/mol. The interference of sex-hormone binding proteins present in human blood plasma was removed by heating. The results of determinations of blood plasma androgen levels obtained by using the direct method were in agreement with those obtained by applying radioimmunoassay with extraction and chromatography. The intra- and inter-assay coefficients of variation were low. (author)

  3. Radioimmunoassay determination of the effect on animal reproduction of alternative of feeding suplementation in dairy cows

    International Nuclear Information System (INIS)

    Villalba, Patricio; Ambuludi, Eduardo

    1993-01-01

    The principal object of this trial was to evaluate the influence of three alternatives of feeding suplementation in dairy cows in the post-partum period in ecuadorian highlands. Thirty sic animals in fist lactation were used in this experiment and were divided in three groups according to the feed intake: Group A diet was 5 Kg. of a commercial concentrate mixture with 12 per cent of crude protein plus pasture ad libitum; Group B diet was green banans (Musa paradisiaca) and pasture and Group C diet was the control only pasture. Using Radioimmunoassay technique (RIA), progesterone values were determinated in milk from each cow. the sampling was sequential, two samples a week, starting 6 days after parturition, until the animal was pregnant or until the study was finished, 150 days after post-partum for each cow. This research allowed us to evaluate the ovaric post-partum activity of each group: Frequency and length of the oestrus cycles; efficiency of oestrus detection, calving-first, oestrus period, calving-conception length, conception rate, and services per conception. Additional datas were used in this study such as: milk production, palpations and treatments

  4. Basic and clinical study on determination of gastrin in the blood by radioimmunoassay

    International Nuclear Information System (INIS)

    Yonahara, Yoshio; Kato, Masayuki; Kashima, Hiroshi; Ito, Yasushi; Takahara, Yoshiko

    1975-01-01

    The usefulness of a radioimmunoassay kit in the determination of gastrin in the blood was examined with the following results. (1) The kit is best used within two weeks during which time its specific radioactivity remains high. Correction of the pH of the buffer solution must be conducted without fail. (2) If the temperature and time of the incubation are strictly controlled, it is possible to obtain almost the same results for each condition of time and temperature. (3) As for reproducibility, scattering was observed to some extent at high concentrations, but little at low concentrations. The recovery rate was as good as 100.6% on the average, indicating the usefulness of this method in clinical tests. (4) In 30 normal subjects, the blood levels of gastrin ranged from 52 to 123 (average 86.8 23.3) pg/ml. In gastric ulcers and duodenal ulcers, it was normal or slightly higher. Further, duodenal ulcers showed higher blood levels than did gastric ulcers, and chronic gastritis showed values slightly higher than normal. It was also interesting that blood levels of gastrin were unusually high in megaloblastic anemias. (author)

  5. Development of a radioimmunoassay for the determination of buprenorphine in biological samples

    International Nuclear Information System (INIS)

    Debrabandere, L.; Boven, M. Van; Daenens, P.

    1993-01-01

    The development of a specific and sensitive radioimmunoassay for the detection of buprenorphine in urine samples is described. With minor adjustments, the assay was also applied to the analysis for buprenorphine in plasma samples. The 2-diazobenzoic acid derivative of buprenorphine has been prepared as a hapten. The immunization of rabbits with the hapten-bovine serum albumin conjugate resulted in the production of antibodies, which cross-reacted with N-dealkylbuprenophine up to about the 90% level. The antibodies showed very low cross-reactivities with the 3-O-glucuronides and with the structural analogue etorphine. The assay was mainly used to prescreen for buprenorphine in urine samples of persons suspected of Temgesic misuse and to determine buprenorphine in plasma samples. A linear calibration graph for buprenorphine was obtained after logit-log regression. The spiking recovery study showed a linear regression. Intra-and inter-assay relative standard deviations were -1 (Student's t-distribution, p 0.01, degrees of freedom = 8). (Author)

  6. A method for tissue extraction and determination of prostate concentrations of endogenous androgens by radioimmunoassay

    International Nuclear Information System (INIS)

    Albert, J.; Geller, J.; Geller, S.; Lopez, D.

    1976-01-01

    A method for simultaneously determining concentrations of major androgens in prostate has been developed. Extraction techniques used to isolate the androgens from minced tissue include homogenization with high-speed blades in Delsal's solvent mixture, adsorption to silica gel, followed by column and one thin-layer chromatography (TLC). Radioimmunoassays (RIA) of small aliquots of TLC eluates are used to quantitate picogram amounts of 5α-dihydrotestosterone (DHT) and 5α-androstanediols (Diol) and to estimate testosterone (T) and androstenedione (Ad). Contamination of blanks was reduced to RIA sensitivity limits primarily by treatment of glassware in a self-cleaning oven. The specificity of the method for each androgen was established by TLC separations of known prostate metabolites, antisera specificities, and parallelism of sample aliquots to androgen RIA standards. The overall precision, in terms of coefficients of variation, was 21% for DHT and 24% for Diol. T and Ad could not be measured with acceptable precision because their very low concentrations in prostate (<=0.5 ng/g tissue) were less than RIA sensitivity limits. Accuracy studies indicated recoveries ranging from 96% for Diol to 121% for DHT. In human benign hypertrophic prostate tissue, DHT averaged 153 ng/g soluble protein (5.8 ng/g tissue) which was 17 times higher than values obtained in human spleen and kidney; Diol in prostate showed no consistent differences from values noted in kidney or spleen

  7. Comparison of the results of testosterone level determinations in the blood from rat spermatic vein obtained by spectrophotometry and radioimmunoassay

    International Nuclear Information System (INIS)

    Buntner, B.

    1980-01-01

    In 28 rats divided into three age groups (40, 60 and 80 days old) the testosterone level was determined in the blood from the spermatic vein by two methods: spectrophotometry and radioimmunoassay. The spectrophotometric method included thin-layer chromatography for separation of steroids. It was observed that the results obtained by RIA were 5-8 times lower than those obtained by spectrophotometry. (author)

  8. Quantitative determination of albumin in urine (microalbuminuria) by electroimmunoassay and radioimmunoassay

    Energy Technology Data Exchange (ETDEWEB)

    Zanazzi, M.; Sverzellati, E.; Scarpioni, L.; Pantano, E.; Cerri, L.; Cecchettin, M.

    1986-10-01

    Electroimmunoassay and radioimmunoassay are two methods specifically designed for rapid and accurate analysis of subclinical amounts of proteins in urine. These assays are very sensitive to detect low concentrations of albumin in urines (17-75 mg/24 hrs) and to discover patients with microalbuminuria. Electroimmunoassay and radioimmunoassay are similar for precision and accuracy. Electroimmunoassay results can be obtained within few hours (3 hrs) and a remarkable advantage is the low cost of the equipment and the reagents. Radioimmunoassay results can be obtained within 2 hours. This assay is useful to perform multiple assays in big laboratories, but electroimmunoassay is much more convenient for little assays, when there are few urine samples to investigate.

  9.  Pleiotropic action of proinsulin C-peptid

    Directory of Open Access Journals (Sweden)

    Michał Usarek

    2012-03-01

    Full Text Available  Proinsulin C-peptide, released in equimolar amounts with insulin by pancreatic β cells, since its discovery in 1967 has been thought to be devoid of biological functions apart from correct insulin processing and formation of disulfide bonds between A and B chains. However, in the last two decades research has brought a substantial amount of data indicating a crucial role of C-peptide in regulating various processes in different types of cells and organs. C-peptide acts presumably via either G-protein-coupled receptor or directly inside the cell, after being internalized. However, a receptor binding this peptide has not been identified yet. This peptide ameliorates pathological changes induced by type 1 diabetes mellitus, including glomerular hyperfiltration, vessel endothelium inflammation and neuron demyelinization. In diabetic patients and diabetic animal models, C-peptide substitution in physiological doses improves the functional and structural properties of peripheral neurons and protects against hyperglycemia-induced apoptosis, promoting neuronal development, regeneration and cell survival. Moreover, it affects glycogen synthesis in skeletal muscles. In vitro C-peptide promotes disaggregation of insulin oligomers, thus enhancing its bioavailability and effects on metabolism. There are controversies concerning the biological action of C-peptide, particularly with respect to its effect on Na /K -ATPase activity. Surprisingly, the excess of circulating peptide associated with diabetes type 2 contributes to atherosclerosis development. In view of these observations, long-term, large-scale clinical investigations using C-peptide physiological doses need to be conducted in order to determine safety and health outcomes of long-term administration of C-peptide to diabetic patients.

  10. Comparative determination of phenytoin by spectrophotometry, gas chromatography, liquid chromatography, enzyme immunoassay, and radioimmunoassay

    International Nuclear Information System (INIS)

    Castro, A.; Ibanez, J.; DiCesare, J.L.; Adams, R.F.; Malkus, H.

    1978-01-01

    Sera from patients being treated with phenytoin were analyzed for the drug by spectrophotometry, gas chromatography, radioimmunoasay, enzyme immunoassay, and liquid chromatography. The assay values obtained were intercompared statistically. Enzyme immunoassay and liquid chromatography appear to be attractive alternatives to the more traditional methods of spectrophotometry and gas chromatography. Our radioimmunoassay data correlated poorly with results by the four other methods

  11. Therapeutic drug monitoring by radioimmunoassay: Determination of aminoglycoside antibiotics and vancomycin in plasma

    International Nuclear Information System (INIS)

    Glaubitt, D.; Drechsler, H.J.; Knoch, K.; Siafarikas, K.

    1984-01-01

    Radioimmunoassay of aminoglycoside antibiotics (gentamicin, tobramycin, netilmicin) or vancomycin in plasma may considerably aid to assess their appropriate dosage and, if necessary, to rapidly adjust it to the assumed requirement. Thus the dosage of the antibiotic is kept large enough as to lead to the desired therapeutic result but not as high as to cause side effects. (orig.)

  12. Comparison of luteinizing hormone and human chorionic gonadotrophin determinations by biological, radioreceptor and radioimmunoassay methods

    International Nuclear Information System (INIS)

    Lange, E.; Paszko, Z.; Padzik, H.

    1980-01-01

    A comparison of the radioreceptor method of assaying LH and HCG with the biological and radioimmunoassay methods is carried out on several preparations of gonadotrophins: human pituitary luteinizing hormone, human menopausal gonadotrophin and human chorionic gonadotrophin. The radioreceptor method better reflects the biological properties of hormones than the radioimmunological method. (author)

  13. Production of peptide antisera specific for mouse and rat proinsulin C-peptide 2

    DEFF Research Database (Denmark)

    Blume, N; Madsen, O D; Kofod, Hans

    1990-01-01

    Mice and rats have two functional non-allelic insulin genes. By using a synthetic peptide representing a common sequence in mouse and rat C-peptide 2 as antigen, we have produced rabbit antisera specific for an epitope which is not present in mouse or rat C-peptide 1. Long-term immunization did...... not seem to increase the end point titre as tested in direct ELISA. The specificity of the antiserum was determined by competitive ELISA and histochemistry on pancreas sections. Only the synthetic C-peptide 2, but not the homologous synthetic C-peptide 1 from mouse and rat competed efficiently in ELISA...... for antibody binding to the immunizing antigen. Antisera to C-peptide 2, stained islet beta-cells on mouse and rat, but not monkey pancreas sections in immunocytochemical analysis. Preabsorption to the synthetic C-peptide 2, but not the synthetic mouse and rat C-peptide 1 abolished staining. In conclusion we...

  14. Use of radioimmunoassay for quantitative determination of progesterone in milk samples from dairy cows in Zimbabwe

    International Nuclear Information System (INIS)

    Freymark, P.J.; McCabe, C.T.

    1986-01-01

    A maximum 90-day service interval is an important economic factor in dairying. The determination of pregnancy at 21 to 26 days post-insemination can ensure that particular attention is paid to non-pregnant cows at subsequent heats, and thus help reduce this interval. In Zimbabwe a radioimmunoassay for milk progesterone using an iodinated tracer was developed in 1982 from a previously established assay for plasma progesterone. Progesterone antiserum is produced locally and the assay is used as an early pregnancy diagnosis test in dairy cattle. During 1983 two pilot schemes were instituted to investigate breed differences, logistics, and feasibility under the local conditions, and to identify constraints. Milk samples taken 24 days post-insemination were found to differentiate best between pregnant and non-pregnant cows for both major breeds in the country (Friesian/Holstein and Jersey). Pregnant cows had an average of 13.76 ng/mL (+-1.06) progesterone on day 24 while non-pregnant cows averaged 0.34 ng/mL (+-0.13) of progesterone. Apparently 12.2% of cows subsequently lost their embryos after day 24, and these cows averaged 9.98 ng/mL (+-1.52). Milk samples were also taken on the day of insemination; the results showed that 11% of cows were incorrectly inseminated when progesterone concentrations were high (2.59 ng/mL+-0.80). A National Early Pregnancy Diagnosis Scheme using milk progesterone was implemented in December 1984 and results to date are discussed in the paper. (author)

  15. Correlation between urinary oestrogen levels determined by haemagglutination inhibition reaction and serum oestradiol levels determined by radioimmunoassay

    International Nuclear Information System (INIS)

    Seki, Katsuyoshi; Seki, Mitsunori; Kato, Koichi

    1985-01-01

    Measurement of urinary or blood oestrogen is essential for a precise monitoring of follicular development in gonadotrophin therapy. Blood oestradiol levels are considered most accurately to reflect follicular maturation. Although radioimmunoassays (RIA) for oestradiol yielding rapid results are now available they require qualified thechnicians and equipment for RIA. Recently, a simple, rapid method for determining urinary total oestrogen has been developed by Mochida Pharmaceutical Co. Ltd., Japan. To determine whether this kit may be applicable to monitoring gonadotrophin therapy, urinary total oestrogen concentrations measured by the kit were compared with serum oestradiol levels determined by RIA in patients who were treated with gonadotrophin. Urinary total oestrogen concentrations in samples obtained either at 07.00 h (first morning urine specimen) or at 09.00 h significantly correlated with serum oestradiol levels. Thus, urinary total oestrogen concentrations determined by the kit appear to reflect follicular development accurately, and are considered applicable to monitoring gonadotrophin therapy. Correction of the urinary total oestrogen concentrations by the creatinine level significantly improved the correlation between urinary total oestrogen values and serum oestradiol levels. Therefore, the primary total oestrogen values should be corrected by the creatinine level. (author)

  16. A simplified radioimmunoassay for digoxin determination using a 125-I-labelled solid-phase kit

    International Nuclear Information System (INIS)

    Doering, W.; Bluemel, E.

    1978-01-01

    Our experience with a commercially available kit (Radioimmunoassay DIGOXIN, Boehringer, Mannheim) using ( 125 J)-labelled digoxin and antibody-coated tubes is reported. This simplified method requires only two pipetting steps per sample and results can be obtained in 70 min. The intra- and interassay coefficient of variation ranged between 7% and 8%. The specific digoxin antibody antibody gave no clinical relevant cross-reactions with spironolactone or prednisone ( [de

  17. Comparative study of radioimmunoassay dates

    International Nuclear Information System (INIS)

    Venegas Sanchez, Ruth.

    1986-01-01

    The radioimmunoassay is frequently used in clinical chemistry for the concentration determination of several substances like hormones as thyrotropine and thyroxine. In this experiment the dates of tyroxine radioimmunoassay are processed by three methods: a) like the recommendation of the IAEA, b) Dr. G. Chase method, c) according to the provider. The best method was Dr. Chase's. (author)

  18. Development and standardization of radioimmunoassay technique for human proinsulin determining and its use in the study of type II diabetes mellitus associated to obesity

    International Nuclear Information System (INIS)

    Nascimento, Martha do

    1996-01-01

    The availability of immunoassay methodology for proinsulin is important to define its physiological and pathophysiological significance in humans. Serum concentration of proinsulin are elevated in patients with type II Diabetes Mellitus (NIDDM) and recently diagnosed Type I, so a raised circulating concentration of proinsulin may serve as an early indicator of β cells dysfunction. recently, in NIDDM the serum concentrations of proinsulin and its B-chain-C-peptide junctional split form, des (31-32), were found to correlate with diastolic blood pressure, a risk factor for cardiovascular disease. The development of a sensitive and specific radioimmunoassay (RIA) methodology for proinsulin has been difficult due to its low concentration in serum and the presence of proinsulin conversion intermediates in fluids and tissues. Also other potentially cross-reactive peptides, including insulin and C-peptide, can interfere in the assay. This work describe a highly specific human proinsulin RIA developed by using biosynthetic human proinsulin (hPI) as immunogen, standard and tracer. (author)

  19. Intracellular Signalling by C-Peptide

    Directory of Open Access Journals (Sweden)

    Claire E. Hills

    2008-01-01

    Full Text Available C-peptide, a cleavage product of the proinsulin molecule, has long been regarded as biologically inert, serving merely as a surrogate marker for insulin release. Recent findings demonstrate both a physiological and protective role of C-peptide when administered to individuals with type I diabetes. Data indicate that C-peptide appears to bind in nanomolar concentrations to a cell surface receptor which is most likely to be G-protein coupled. Binding of C-peptide initiates multiple cellular effects, evoking a rise in intracellular calcium, increased PI-3-kinase activity, stimulation of the Na+/K+ ATPase, increased eNOS transcription, and activation of the MAPK signalling pathway. These cell signalling effects have been studied in multiple cell types from multiple tissues. Overall these observations raise the possibility that C-peptide may serve as a potential therapeutic agent for the treatment or prevention of long-term complications associated with diabetes.

  20. Presence of melatonin in various cat brainstem nuclei determined by radioimmunoassay

    International Nuclear Information System (INIS)

    Sallanon, M.; Touret, M.; Claustrat, B.

    1982-01-01

    Microdissected samples of juvenile cat brain tissue were assayed for melatonin content using a double antibody radioimmunoassay. Immunoreactive melatonin was consistently detected, albeit in variable amounts, in pineal, habenula, the region of the nucleus gracilis, gigantocellular reticular formation of the pons and medulla oblongata. Among the negative areas were raphe nuclei, substantia nigra dn locus caeruleus. These findings suggest that melatonin may play a role in some structures of the central nervous system outside the pineal-hypothalamo-pituitary axis. This immunoreactive melatonin could reflect a local synthesis, or a tissular uptake of melatonin from blood or cerebrospinal fluid. (author)

  1. Evaluation of a radioimmunoassay for the determination of anti-native DNA antibodies

    International Nuclear Information System (INIS)

    Johanet, C.; Soulie, E.; Absalon, Y.B.; Ocwieja, T.; Abuaf, N.

    1991-01-01

    The anti-native DNA antibodies were measured by a radioimmunoassay (RIA) type Farr assay in the sera from 648 patients: 108 with active or inactive systemic lupus erythematosus (SLE), 181 with clinical symptoms of another connective tissue disease, 171 with liver diseases, 29 with different pathology and 159 normal sera were obtained from a blood bank. The anti-DNA kit has been calibrated against the first international units/ml. This assay has proved to be sensitive and specific, and appears to be reliable for the diagnosis and follow-up of SLE patients. The authors propose a new reference cut-off level higher than producer's one [fr

  2. Thyroxine determination in serum by radioimmunoassay and competitive protein-binding analysis (simultaneous study using four test kits)

    International Nuclear Information System (INIS)

    Wagner, K.

    1978-01-01

    Three commercial test kits for radioimmunological T 4 -determination have been tested (T 4 -RIA Abbott, RIA-mat T 4 , T 4 -RIA Henning). The RIA method has also been compared with a CPBA test (Tetralute) for routine application. 1) The results show that CPBA (Tetralute) is superior over the three radioimmuno-assays with regard to intra-assay variance. The T 4 -RIA Abbott has been inferior to the two other RIA under test and to the Tetralute with regard to inter-assay variance. 2) The four test kits show significant differences and considerable deviations from the given nominal values in comparison with the mean values of two control sera. A control for correctness does not seem to be appropriate as it cannot be decided which of the test kits yields the true value of T 4 content. No systematic difference has been observed between RIA and CPBA in the determination of T 4 in control sera. 3) No detectable difference has been found among the RIA-T 4 test kits and comparing them with the CBPA test regarding their diagnostic precision. A good correlation of T 4 values of euthyroid patients comparing the Tetralute and the three radioimmunological test kits. The mean values of euthyroid sera obtained by the three radioimmuno-assays and the Tetralute are not in agreement with each other. (orig.) [de

  3. Radioimmunoassay for biopterin

    International Nuclear Information System (INIS)

    Nagatsu, Toshiharu; Yamaguchi, Tokio; Kato, Takeshi; Sugimoto, Takashi; Matsuura, Sadao.

    1979-01-01

    Specific antibodies against biopterin, neopterin, and 6,7-dimethylpterin were prepared and a new type of radioimmunoassay, to which these pterins were subjected was developed. This new type of radioimmunoassay was used to determine biopterin in human urine. Specific antiserum against biopterin did not crossreact significantly with tetrahydro-biopterin, dihydro-biopterin, neopterin, 6,7-dimethylpterin, pterin, or folic acid and showed 30% binding of biopterinyl-caproyl- ( 125 I ) tyramide at a dilution of 1:800. The antisera against neopterin and dimethylpterin also showed a high specificity and did not cross-react significantly with the other pterins. The sensitivity of the radioimmunoassay was increased about ten-fold by pre-incubating the antiserum with 6,7-dimethylpterinyl-caproyl to remove antibodies against the caproic acid moiety of the biopterin conjugate. The recovery of biopterin or tetrahydro-biopterin added human urine was nearly 100% according to this type of radioimmunoassay, and the biopterin concentrations in the urine that were obtained by means of this type of radioimmunoassay showed a fairly good agreement with the values obtained by means of bioassay. The biopterin contents per milliliter of human urine showed considerable variations depending on the subjects, but those per milligram of creatinine were found to be fairly constant in normal subjects. Therefore, biopterin concentrations per milligram of creatinine in human urine may be a good indicator of biopterin metabolism in clinical chemistry. This new type of radioimmunoassay is simple, highly specific, and reproducible. Therefore, it may be very useful for the screening of atypical phenylketonuria due to biopterin deficiency and also for the study of the pathogenesis of various biopterin metabolic diseases. (J.P.N.)

  4. Development of SI-traceable C-peptide certified reference material NMIJ CRM 6901-a using isotope-dilution mass spectrometry-based amino acid analyses.

    Science.gov (United States)

    Kinumi, Tomoya; Goto, Mari; Eyama, Sakae; Kato, Megumi; Kasama, Takeshi; Takatsu, Akiko

    2012-07-01

    A certified reference material (CRM) is a higher-order calibration material used to enable a traceable analysis. This paper describes the development of a C-peptide CRM (NMIJ CRM 6901-a) by the National Metrology Institute of Japan using two independent methods for amino acid analysis based on isotope-dilution mass spectrometry. C-peptide is a 31-mer peptide that is utilized for the evaluation of β-cell function in the pancreas in clinical testing. This CRM is a lyophilized synthetic peptide having the human C-peptide sequence, and contains deamidated and pyroglutamylated forms of C-peptide. By adding water (1.00 ± 0.01) g into the vial containing the CRM, the C-peptide solution in 10 mM phosphate buffer saline (pH 6.6) is reconstituted. We assigned two certified values that represent the concentrations of total C-peptide (mixture of C-peptide, deamidated C-peptide, and pyroglutamylated C-peptide) and C-peptide. The certified concentration of total C-peptide was determined by two amino acid analyses using pre-column derivatization liquid chromatography-mass spectrometry and hydrophilic chromatography-mass spectrometry following acid hydrolysis. The certified concentration of C-peptide was determined by multiplying the concentration of total C-peptide by the ratio of the relative area of C-peptide to that of the total C-peptide measured by liquid chromatography. The certified value of C-peptide (80.7 ± 5.0) mg/L represents the concentration of the specific entity of C-peptide; on the other hand, the certified value of total C-peptide, (81.7 ± 5.1) mg/L can be used for analyses that does not differentiate deamidated and pyroglutamylated C-peptide from C-peptide itself, such as amino acid analyses and immunochemical assays.

  5. Determination of antibody levels to Candida albicans in healthy and hospitalised adults using a radioimmunoassay

    International Nuclear Information System (INIS)

    Cobb, S.J.; Parratt, D.

    1978-01-01

    A radioimmunoassay for antibody to Candida albicans is described. The test uses whole, killed of organisms as the antigen and radiolabelled sheep anti-human globulins to quantitate different classes of antibody to C. albicans. The assay has been compared with an Ouchterlony precipitin method and found to be simpler, more rapid, and more sensitive than the latter. Results obtained from two groups of symptomless adults indicated that the range of antibody level was wider for a hospitalised group than for a group of blood transfusion donors, particularly in respect of IgG and IgA antibody. The reason for the increase of antibody in hospital patients was not clear but may have been related to antibiotic therapy. The difficulties in interpretation of Candida serology have therefore been re-assessed in the light of more detailed knowledge of the range and type of antibody to be expected in normal individuals. (author)

  6. Determination of the complement components C1q, C4 and C3 in serum and cerebrospinal fluid by radioimmunoassay

    Energy Technology Data Exchange (ETDEWEB)

    Dujardin, B.C.G.; Roijers, A.F.M.; Driedijk, P.C.; Out, T.A.

    1985-06-25

    Non-competitive 2-site radioimmunoassays (RIA) for the determination of the complement proteins C1q, C4 and C3 in cerebrospinal fluid (CSF) are described. The quantitative results of the RIAs were the same as those obtained by other assay methods: radial immunodiffusion and turbidimetry and, in the case of C4, the haemolytic assay. The ratios (concentration in CSF)/(concentration in serum) of the complement proteins correlated poorly with that of albumin. In contrast, the ratio of IgG was significantly correlated with that of albumin. The ratios of the complement proteins were higher than might be expected on the basis of their molecular masses. This suggests that these proteins may be synthesized within the normal central nervous system. (Auth.). 20 refs.; 3 figs.; 3 tabs.

  7. Heterogeneity of human plasma insulin: techniques for separating immunoreactive components and their determination by radioimmunoassay

    International Nuclear Information System (INIS)

    Souza, Iracelia Torres de Toledo e

    1977-01-01

    When human plasma is filtered on Sephadex G-SO fine, insulin immunoreactivity is recovered in two peaks: 'big insulin', the higher molecular weight component and 'little insulin', the lower molecular component, having elution volumes that correspond to those of porcine proinsulin 125 I and porcine insulin 125 I respectively. The presence of another form of immunoreactive insulin 'big big insulin' was detected from an insuloma suspect and its elution pattern corresponding to serum albumin. The eluates correspondent to 'big' and 'little' insulin as well as 'big big' component were assayed by radioimmunoassay using crystalline human insulin as a standard, porcine insulin 125 tracer and anti insulin serum. The antibody, raised in guinea-pigs, was sensitive and potent being adequate for the assay. The reactivity of insulin and proinsulin was tested against the antibody. The relative proportions of several components of total immunoreactive insulin in plasma were studied in basal conditions in five normal subjects and in the patient JSC with pancreatic insulin-secreting tumor as well as after glucose stimuli in all tolbutamide in JSC. (author)

  8. Radioimmunoassay apparatus

    International Nuclear Information System (INIS)

    1981-01-01

    Apparatus for performing a quantitative radioimmunoassay comprising: a substantially spherical bead for carrying an antibody and a gripper for gripping said bead, said gripper comprising an integrally formed unit having a single elongate handle portion and a plurality of resilient fingers arranged at the base of the handle so that when said bead is secured within said fingers, said bead may be freely rotated about any diametric axis of the bead. In particular the invention relates to an apparatus for a two site immunoradiometric assay for serum ferritin in human blood samples. (author)

  9. Pregnancy-induced rise in serum C-peptide concentrations in women with type 1 diabetes

    DEFF Research Database (Denmark)

    Nielsen, Lene Ringholm; Rehfeld, Jens F; Pedersen-Bjergaard, Ulrik

    2009-01-01

    OBJECTIVE: The purpose of this study was to investigate whether pregnancy induces increased insulin production as a marker of improved beta-cell function in women with long-term type 1 diabetes. RESEARCH DESIGN AND METHODS: This was a prospective study of 90 consecutive pregnant women with type 1...... diabetes. At 8, 14, 21, 27, and 33 weeks blood samples were drawn for measurements of A1C, C-peptide, and serum glucose. C-peptide (detection limit: 6 pmol/l) was considered stimulated at a corresponding serum glucose concentration >or=5.0 mmol/l. GAD antibody concentration was determined at 8 and 33 weeks...... in 35 women. RESULTS: C-peptide concentrations gradually increased throughout pregnancy regardless of serum glucose concentrations in the 90 women with a median duration of diabetes of 17 years (range 1-36 years). Among 35 women with paired recordings of stimulated C-peptide, C-peptide production...

  10. Changes of serum leptin and c-peptide level in children with type 1 diabetic mellitus

    International Nuclear Information System (INIS)

    Du Tongxin; Wang Zizheng; Sun Junjiang; Wang Shukui; Qi Shaokang

    2001-01-01

    To deplore the relationship between leptin and c-peptide in children with type 1 diabetic mellitus (DM). The levels of serum leptin and c-peptide (C-P) in 65 type 1 DM children (including 31 before and after insulin treatment) and 30 normal controls were measured by radioimmunoassay (RIA). The results found that there was significant differences (P < 0.01) in leptin and C-P between DM children and normal controls, also in 31 DM children before and after treatment. It showed a positive correlation between leptin and C-P. The changes of the leptin/C-P ratio in DM children compared with normal controls and that before and after treatment were also significantly different. It suggested that leptin may have close relationship in the development, progress and the occurrence of complications in children with DM and also provide a new clue for their diagnosis treatment and complication occurrence

  11. Progesterone radioimmunoassay

    International Nuclear Information System (INIS)

    Allen, R.M.; Redshaw, M.R.

    1981-01-01

    This patent claims a radioimmunoassay for progesterone, which comprises contacting, in an acidic medium a sample of liquid with a predetermined amount of antibodies raised against a progesterone-protein complex, the protein being attached to the 11-position of progesterone by means of a bridging group and with a predetermined amount of a progesterone derivative having an iodinatable group attached to its 3-position by means of a bridging group, the iodinatable group being iodinated with one or more atom(s) of a radioisotope of iodine, separating the steroid bound in the resulting antibody-antigen complex from the free steroid and measuring the radioactivity of the free steroid component or of the antibody-antigen complex. Sufficient sensitivity has been achieved to enable a progesterone assay to be carried out directly on a sample of biological fluid, such as serum, plasma, urine or milk. (U.K.)

  12. Sensitivity and reproducibility of urinary C-peptide as estimate of islet B-cell function in insulin-treated diabetes

    DEFF Research Database (Denmark)

    Gjessing, H J; Matzen, L E; Faber, O K

    1989-01-01

    The aims of the present study were to evaluate the ability of urinary C-peptide determination to demonstrate presence of residual insulin secretion, and to evaluate the reproducibility of urinary C-peptide excretion in 125 insulin-treated diabetic patients. C-peptide was determined in two...

  13. Simple way to determine nonspecific effects of plasma and serum components in radioreceptor assays and radioimmunoassays for human chorionic gonadotropin

    International Nuclear Information System (INIS)

    Rao, C.V.; Hussa, R.O.

    1982-01-01

    A simple approach is validated for the determination of nonspecific effects of human plasma and serum in the radioreceptor assays and radioimmunoassays for human chorionic gonadotropin (hCG). The approach is based on the findings that, despite differences in the degree of inhibition of 125 I-hCG binding to its receptors and antibodies by nonhormonal components in different dilutions of pool plasma and serum, the standard curves (plotted as the percentage of control for each serum or plasma dilution) are superimposable. The approach consists of (1) running a single standard curve with no pool plasma or serum, (2) including a set of ''correction'' tubes which contain pool plasma or serum diluted correspondingly to the dilution of the unknown samples in the assay, (3) dividing the counts per minute found in the correction tubes into the counts per minute of the unknown samples and multiplying by 100, and (4) using this value to obtain the amount of hCG in the unknown samples by comparison with the no pool plasma or serum standard curve

  14. Simple way to determine nonspecific effects of plasma and serum components in radioreceptor assays and radioimmunoassays for human chorionic gonadotropin

    International Nuclear Information System (INIS)

    Rao, C.V.; Hussa, R.O.

    1982-01-01

    A simple approach is validated for the determination of nonspecific effects of human plasma and serum in the radioreceptor assays and radioimmunoassays for human chorionic gonadotropin (hCG). The approach is based on the findings that, despite differences in the degree of inhibition of 125 I-hCG binding to its receptors and antibodies by nonhormonal components in different dilutions of pool plasma and serum, the standard curves (plotted as the percentage of control for each serum or plasma dilution) are superimposable. The approach consists of (1) running a single standard curve with no pool plasma or serum, (2) including a set of correction tubes which contain pool plasma or serum diluted correspondingly to the dilution of the unknown samples in the assay, (3) dividing the counts per minute found in the correction tubes into the counts per minute of the unknown samples and multiplying by 100, and (4) using this value to obtain the amount of hCG in the unknown samples by comparison with the no pool plasma or serum standard curve

  15. Polyacrylamide gel electrophoretic preparation of labelled and non-labelled peptides for radioimmunoassay

    International Nuclear Information System (INIS)

    Besch, W.; Woltanski, K.P.; Keilacker, H.; Kohnert, K.D.

    1986-01-01

    Radioiodinated polypeptide hormones, such as insulin, glucagon, human growth hormone, and human C-peptide are employed for radioimmunoassays for investigation of hormonal alterations in states of disturbed carbohydrate metabolism. Iodination was performed using chloramine T. Iodination products of these polypeptide hormones and, for preparation of standard material, native human C-peptide from cadaver pancreases were fractionated by polyacrylamide gel electrophoresis at pH 8.9. Disc electrophoresis in 24 cm long gel rods resulted in stable tracers with high specific activity as well as homogeneous standard material being highly suitable for radioimmunoassays. (author)

  16. Radioimmunoassay of buprenorphine

    Energy Technology Data Exchange (ETDEWEB)

    Bartlett, A.J.; Lloyd-Jones, J.G.; Rance, M.J.; Flockhart, I.R.; Dockray, G.J.; Bennett, M.R.D.

    1980-01-01

    Antisera to buprenorphine were obtained in rabbits immunised with 3-0-carboxymethylbuprenorphine and N-hemisuccinyl-norbuprenorphine conjugated to bovine serum albumin. Using the latter antiserum and tritium labelled buprenorphine a radioimmunoassay having good accuracy and precision was developed for concentrations as low as 50 picograms in 1 ml of plasma. The N-hemisuccinyl antiserum crossreacted with norbuprenorphine, and the 3-0-glucuronide conjugate with the 3-0-carboxy-methyl antiserum. Cross-reactivity of both antisera to other pharmacologically related compounds was negligible. The assay was employed to determine plasma buprenorphine concentration following its parenteral administration to dog and man.

  17. Plasma levels of triamcinolone acetonide as determined by radioimmunoassay after topical application

    International Nuclear Information System (INIS)

    In this paper a method for the radioimmunological determination of triamcinolone acetonide (TAAc) in plasma is described. The antiserum used in the radioimmunological determinations showed high specifity for TAAc; the minimal detectable amount was 0.2 ng. The course of the plasma concentrationtime curve of TAAc after intravenous injection into rats was analysed. The concentration of TAAc in the blood of the patients after topical application of the drug is very low. No detectable amount of TAAc was found in the blood of out-patients. Hospitalized patients treated with TAAc under plastic occlusion showed plasma levels ranging from 0.8 to 3.4 ng/ml. This level remained constant throughout the treatment. (orig.) 891 AJ [de

  18. Peptide radioimmunoassays in clinical medicine

    International Nuclear Information System (INIS)

    Geokas, M.C.; Yalow, R.S.; Straus, E.W.; Gold, E.M.

    1982-01-01

    The radioimmunoassay technique, first developed for the determination of hormones, has been applied to many substances of biologic interest by clinical and research laboratories around the world. It has had an enormous effect in medicine and biology as a diagnostic tool, a guide to therapy, and a probe for the fine structure of biologic systems. For instance, the assays of insulin, gastrin, secretin, prolactin, and certain tissue-specific enzymes have been invaluable in patient care. Further refinements of current methods, as well as the emergence of new immunoassay techniques, are expected to enhance precision, specificity, reliability, and convenience of the radioimmunoassay in both clinical and research laboratories

  19. Changes in pancreatic somatostatin content in spontaneously diabetic mice, as determined by radioimmunoassay and immunohistochemical methods

    International Nuclear Information System (INIS)

    Makino, H.; Matsushima, Y.; Kanatsuka, A.; Yamamoto, M.; Kumagai, A.; Nishimura, M.

    1979-01-01

    A specific RIA for somatostatin (SRIF) was used to determine the SRIF content of the pancreas and hypothalamus in spontaneously diabetic C57BL/KsJ dbdb and C57BL/6J obob mice. In addition, SRIF- and glucagon-containing cells were examined in the pancreatic islets with an immunohistochemical technique. In dbdb mice, immunoassayable pancreatic SRIF content was increased, as was the number of SRIF- or glucagon-containing cells. In obob mice, immunoassayable pancreatic SRIF content was also increased, but no increase was noted in the number of SRIF- or glucagon-containing cells. The hypothalamic SRIF content of either strain was not different from that of controls. These results regarding pancreatic SRIF content were in accord with some but not all previous reports. These differences may be related to the age of the mice or to the conditions in which they were bred. The pancreatic SRIF increase in both dbdb and obob mice may be attributable to hyperglucagonemia, hyperglycemia, or a decrease in insulin action. Further work is necessary to clearly delineate the mechanism

  20. C-Peptides for diagnostics and therapy: a veterinary medicine point of view

    Directory of Open Access Journals (Sweden)

    Derek A. Rosenfield

    Full Text Available ABSTRACT: Empirical studies proved that C-peptides are performing numerous intrinsic biological roles, and serve as a marker for pancreatic performance analysis. Since the last decade, C-peptide assays for differential diagnosis in veterinary diabetic patients are becoming more available, but still only for a very limited number of species. Studies on C-peptide as a diagnostic tool, therapy for associated complications, or as replacement therapies for C-peptide deficiency still showed not to be a common practice in veterinary medicine. This review was conducted to determine the potential importance of C-peptide in Veterinary Medicine, relevant in the diagnosis of diabetes and for other metabolic processes, as well as its proposed therapeutic benefits. Numerous articles were identified that reported positive results in their experimental studies, whether C-peptide as a biomarker for pancreatic performance in dogs, cats, and horses, as a non-invasive method to monitor nutritional status in primates, or to investigate its potential therapeutic benefits for diabetes-related illnesses.

  1. Fasting plasma C-peptide, glucagon stimulated plasma C-peptide, and urinary C-peptide in relation to clinical type of diabetes

    DEFF Research Database (Denmark)

    Gjessing, H J; Matzen, L E; Faber, O K

    1989-01-01

    diabetic subjects. Patients were classified clinically as Type 1 (insulin-dependent) diabetic subjects in the presence of at least two of the following criteria: 1) significant ketonuria, 2) insulin treatment started within one year after diagnosis, 3) age of diagnosis less than or equal to 40 years, and 4...... islet B-cell function and were separated according to the 20%, 40%, 60% and 80% C-peptide percentiles. The two classifications of patients were compared by calculating the prevalence of clinical Type 1 and Type 2 diabetes in each of the C-peptide classes. This analysis showed that patients......Many patients with Type 2 (non-insulin-dependent) diabetes mellitus are treated with insulin in order to control hyperglycaemia. We studied fasting plasma C-peptide, glucagon stimulated plasma C-peptide, and 24 h urinary C-peptide in relation to clinical type of diabetes in 132 insulin treated...

  2. Progesterone radioimmunoassay

    International Nuclear Information System (INIS)

    Stroufova, A.; Kozlova, J.

    1976-01-01

    RIA methods of determining progestorone using the SORIN kit made in Italy and the NEN kit made in Great Britain were compared. Plasma extraction, the initial sample size for examination and recovery, the range of calibration curves of the two kits, the variation coefficient, the values of the blank sample and the values of progesterone determined in the normal menstrual cycle are discussed in detail. Variation coefficient: Sorin (calibration curve 9 to 11%, biological material 9.2%), NEN (calibration curve 12%, biological material 27.8%); determinations of progesterone levels during a normal menstrual cycle were 10 to 15% higher with the NEN kit; tritiated samples were measured with a 30 to 37% efficiency using the SORIN kit and 15 to 18% efficiency using the NEN kit. The turbidity and later sediment which formed during the determination of steroid hormones in biological materials after the addition of the scintillation solution did not reduce the efficiency of measurement. Priority is given to the SORIN kit. (L.O.)

  3. Microsampling Collection Methods for Measurement of C-peptide in Whole Blood.

    Science.gov (United States)

    Jones, Charlotte; Dunseath, Gareth J; Lemon, Jessica; Luzio, Stephen D

    2018-03-01

    Microsampling techniques are alternative methods to venous sampling for obtaining blood for measurement of circulating biomarkers, offering the convenience of reduced sample volume and elimination of the need for phlebotomists. Dried blood spot (DBS) microsampling methods have been used for many years while more recently a volumetric absorptive microsampling device (VAMS™) has been introduced. In diabetes mellitus, circulating C-peptide is commonly used as an indicator of endogenous insulin secretion and clinical measurement can aid in diagnosis as well as informing on therapy. This pilot study investigated the effectiveness of microsampling collection of capillary blood for measurement of C-peptide. Capillary blood was collected into capillary tubes and centrifuged for plasma samples. Simultaneous samples were also collected using both microsampling methods (DBS and VAMS). Blood from both microsamplers was extracted prior to assaying for C-peptide alongside the corresponding plasma samples, using specific immunoassays and results obtained from microsampling compared to the reference plasma concentrations. Stability was determined by collecting duplicate DBS and VAMS and assaying both in a single assay after storing one at -20°C immediately and one at room temperature for 48 hours post-collection. Good agreement was observed between C-peptide concentrations in plasma and equivalent DBS and VAMS samples ( R 2 = .929 and .9231, DBS and VAMS, respectively), with mean differences of 75.7 and 8.4 pmol/L observed for DBS and VAMS. Small decreases in C-peptide of 11.6% and 0.1% were observed after 48 hours storage for DBS and VAMS, respectively. C-peptide collected using DBS and VAMS showed good agreement with reference plasma concentrations, suggesting both would be an effective microsampling method for collection and measurement of C-peptide.

  4. Canine C-peptide for characterization of experimental diabetes in dogs

    International Nuclear Information System (INIS)

    Fischer, U.; Besch, W.; Freyse, E.-J.

    1985-01-01

    Radioimmunoassay of canine C-peptide (CCP) was developed for the characterization of endogenous beta cell function in experimentally diabetic dogs. The animals were rendered diabetic by subtotal pancreatectomy and intrasurgical infusion of 2 mg/kg streptozotocin into the superior pancreaticoduodenal artery. After an average duration of diabetes of 5 months the animals showed zero peripheral venous fasting CCP levels with no response to feeding, OGTT/i.v. glucagon loading or i.v. glucose tolerance testing. The data on CCP levels entirely coincided with simultaneously measured plasma IRI levels. In non-diabetic control animals clear-cut CCP increases were observed after all stimuli. The experimental model provided an IDDM-type diabetes without toxic symptoms but with a sufficient exocrine pancreatic function. The comparison showed that plasma IRI analyses would also allow reliable characterization of insulinogenic functions in these animals. (author)

  5. Radioimmunoassay of erythropoietin

    International Nuclear Information System (INIS)

    Goldwasser, E.; Sherwood, J.B.

    1981-01-01

    A brief review of the historical development of the radioimmunoassay (RIA) for serum erythropoietin is given. It has been shown that there is reasonable agreement between the results obtained by RIA and those obtained by the previously used bioassay. By RIA, a mean normal serum titre of 18 mu/ml erythropoietin has been determined in a study of 445 individuals. Serum erythropoietin results for patients with polycythaemia vera have not been shown to be significantly different from normal values but in patients with secondary polycythaemia, serum titres averaging 94 mu/ml have been found. The predicted physiological changes in erythropoietin titre have also been demonstrated in humans using the RIA; increasing after bleeding and decreasing after red cell administration. Studies of erythropoietin levels in experimental animals have shown that, with the particular antiserum used, the sensitivity of the RIA is markedly reduced. (U.K.)

  6. Radioimmunoassay of anabolic steroids

    International Nuclear Information System (INIS)

    Hampl, R.; Stranska, I.; Starka, L.; Picha, J.; Chundela, B.

    1978-01-01

    Alternative antisera against 17 α-methyltestosterone and 19-nortestosterone were raised and used for radioimmunoassay of anabolic steroids. Tritiated compounds were used as radioligands. The RIA method suitable for doping control is proposed for 17 α-alkylated anabolic steroids in both plasma and urine, using qoat antiserum against methyltestosterone-3-carboxymethyloxime-BSA. Sensitivity of the method was expressed as least amount of nonradioactive methandienone which, when added to normal urine or plasma, caused statistically significant decrease of measured supernatant radioactivity at 99% level. The amounts from 50 to 500 pg were tested, each in eight parallel determinations. The amounts of 100 pg for plasma and 200 pg for urine met these criteria. The respective coefficients of variation did not depend on the amount of steroid added in this range. They averaged 4.60% for plasma and 4.95% for urine, respectively. (T.I.)

  7. C-Peptide Effects on Renal Physiology and Diabetes

    Directory of Open Access Journals (Sweden)

    M. Tsimaratos

    2008-05-01

    Full Text Available The C-peptide of proinsulin is important for the biosynthesis of insulin and has for a long time been considered to be biologically inert. Animal studies have shown that some of the renal effects of the C-peptide may in part be explained by its ability to stimulate the Na,K-ATPase activity. Precisely, the C-peptide reduces diabetes-induced glomerular hyperfiltration both in animals and humans, therefore, resulting in regression of fibrosis. The tubular function is also concerned as diabetic animals supplemented with C-peptide exhibit better renal function resulting in reduced urinary sodium waste and protein excretion together with the reduction of the diabetes-induced glomerular hyperfiltration. The tubular effectors of C-peptide were considered to be tubule transporters, but recent studies have shown that biochemical pathways involving cellular kinases and inflammatory pathways may also be important. The matter theory concerning the C-peptide effects is a metabolic one involving the effects of the C-peptide on lipidic metabolic status.This review concentrates on the most convincing data which indicate that the C-peptide is a biologically active hormone for renal physiology.

  8. Sensitivity and reproducibility of urinary C-peptide as estimate of islet B-cell function in insulin-treated diabetes

    DEFF Research Database (Denmark)

    Gjessing, H J; Matzen, L E; Faber, O K

    1989-01-01

    The aims of the present study were to evaluate the ability of urinary C-peptide determination to demonstrate presence of residual insulin secretion, and to evaluate the reproducibility of urinary C-peptide excretion in 125 insulin-treated diabetic patients. C-peptide was determined in two...... of 125 patients were without residual insulin secretion. In contrast to this, only 7 patients were diagnosed as C-peptide nonsecretors using the analytical detection limit of urinary C-peptide. Eighty-four per cent of patients considered to have Type 1 (insulin-dependent) diabetes with a duration...... of diabetes of more than 15 years had detectable C-peptide in the urine.(ABSTRACT TRUNCATED AT 250 WORDS)...

  9. Setting-up and validation of two radioimmunoassay methods for determination of plasma progesterone concentration in mares, cows and rats

    International Nuclear Information System (INIS)

    Rosa e Silva, A.A.M.; Caldas, M.C.S.; Campos, L.M.A.; Gradela, A.

    1993-01-01

    Two reliable radioimmunoassay (RIA) methods which permits the measurement of progesterone (P 4 ) in plasma of equine, bovine and rats are described. After extraction of plasma with diethylic ether the RIA methods were performed. The first one utilizes 125 I progesterone (double antibody method) and the other 1,2,6,7,16, 17 3 H progesterone (adsorption in charcoal/dextran). Both two methods were suitable in the valuation of plasma P 4 concentration in different physiological reproductive conditions. The method of the double antibody showed higher sensibility beyond to be less expensive than the other method. Despite it, the two RIA methods were much less expensive than available commercial Kits in the market. (author)

  10. Radioimmunoassay for determination of blood aldosterone and renin in the diagnosis of some forms of arterial hypertension

    International Nuclear Information System (INIS)

    Khamidov, R.I.; Khalmuratova, R.A.; Sattarova, F.K.

    1987-01-01

    Aldosterone concentration and renin activity in the blood from the ulnar, inferior cava veins at the level of the 12th thoracic vertebra, the left and right renal veins were studied in 60 patients with arterial hypertension by means of a radioimmunoassay kits (France). The patients were divided into 4 groups: with primary and idiopathic hyperaldosteronism, renal-parenchymatous and essential arterial hypertension. The diagnosis of primary and idiopathic hyperaldosteronism was also confirmed by low blood renin activity. Renin activity in the peripheral venous blood was considerably elevated in renal-parenchymatous arterial hypertension and was normal in essential hypertension. Aldosterone concentration in the blood from the vena cava inferior and renal veins was 1.6-2-fold as high on the affected side as on the contralateral one

  11. Proinsulin C-peptide interferes with insulin fibril formation

    International Nuclear Information System (INIS)

    Landreh, Michael; Stukenborg, Jan-Bernd; Willander, Hanna; Söder, Olle; Johansson, Jan; Jörnvall, Hans

    2012-01-01

    Highlights: ► Insulin and C-peptide can interact under insulin fibril forming conditions. ► C-peptide is incorporated into insulin aggregates and alters aggregation lag time. ► C-peptide changes insulin fibril morphology and affects backbone accessibility. ► C-peptide may be a regulator of fibril formation by β-cell granule proteins. -- Abstract: Insulin aggregation can prevent rapid insulin uptake and cause localized amyloidosis in the treatment of type-1 diabetes. In this study, we investigated the effect of C-peptide, the 31-residue peptide cleaved from proinsulin, on insulin fibrillation at optimal conditions for fibrillation. This is at low pH and high concentration, when the fibrils formed are regular and extended. We report that C-peptide then modulates the insulin aggregation lag time and profoundly changes the fibril appearance, to rounded clumps of short fibrils, which, however, still are Thioflavine T-positive. Electrospray ionization mass spectrometry also indicates that C-peptide interacts with aggregating insulin and is incorporated into the aggregates. Hydrogen/deuterium exchange mass spectrometry further reveals reduced backbone accessibility in insulin aggregates formed in the presence of C-peptide. Combined, these effects are similar to those of C-peptide on islet amyloid polypeptide fibrillation and suggest that C-peptide has a general ability to interact with amyloidogenic proteins from pancreatic β-cell granules. Considering the concentrations, these peptide interactions should be relevant also during physiological secretion, and even so at special sites post-secretory or under insulin treatment conditions in vivo.

  12. Stimulated urine C-peptide creatinine ratio vs serum C-peptide level for monitoring of β-cell function in the first year after diagnosis of Type 1 diabetes.

    Science.gov (United States)

    Tatovic, D; Luzio, S; Dunseath, G; Liu, Y; Alhadj Ali, M; Peakman, M; Dayan, C M

    2016-11-01

    To determine if urine C-peptide/creatinine ratio is a useful tool for monitoring β-cell function in new-onset Type 1 diabetes. Data were obtained from a prospective immunomodulation study in people with Type 1 diabetes ≤ 3 months from diagnosis, with a standard mixed-meal tolerance test and measurement of urine C-peptide/creatinine ratio carried out at 0, 3, 6, 9 and 12 months. The change in the insulin-dose-adjusted HbA 1c level was also correlated with the change in serum/urine C-peptide level during the 12-month follow-up period. A significant reduction in urine C-peptide/creatinine ratio, measured after a mixed-meal, was reached at 9 months (-45.4%), whilst the reduction in stimulated serum C-peptide level reached significance after 3 months (-54.7%) in placebo-treated participants. Neither change in stimulated serum C-peptide nor change in urine C-peptide level correlated with each other, and nor did change in insulin-dose-adjusted HbA 1c level in the first 6 months, but all measures correlated significantly in the second half of the 12-month follow-up period. Mixed-meal-stimulated urine C-peptide/creatinine ratio was similar to, although less sensitive than, stimulated serum C-peptide level in monitoring β-cell function during the first year after diagnosis. Because the former is significantly less invasive, it warrants inclusion in further studies in Type 1 diabetes and may represent an attractive alternative outcome measure in cohort studies and in children. © 2016 Diabetes UK.

  13. A sensitive radioimmunoassay for fentanyl

    International Nuclear Information System (INIS)

    Michiels, M.; Hendriks, R.; Heykants, J.

    1977-01-01

    Antiserum to fentanyl was obtained in rabbits repeatedly injected with carboxyfentanyl conjugated to bovine serum albumin. Using the antiserum, a highly sensitive radioimmunoassay has been developed, based on the dextran-coated charcoal method. It proved possible to assay the drug directly in plasma, in amounts as small as 30 picogram in 0.5 ml. The antibody was highly specific for fentanyl and no cross-reaction was observed with its major metabolites. This sensitive and specific radioimmunoassay method was employed to determine fentanyl in plasma from six volunteers after an intravenous bolus of 0.2 mg, and in plasma from dogs treated both intravenously and subcutaneously with 0.02 mg/kg. The plasma level of fentanyl could be followed for up to 6 h after a therapeutic dose in dogs and man. (orig.) [de

  14. Reference intervals for C-peptide and insulin derived from a general adult Danish population.

    Science.gov (United States)

    Larsen, Pia Bükmann; Linneberg, Allan; Hansen, Torben; Friis-Hansen, Lennart

    2017-05-01

    Despite international efforts to standardize C-peptide and insulin calibrators and immunoassays, platform dependent differences still exist, and platform specific reference intervals are hence needed for correct interpretation. We therefore wanted to establish traceable reference intervals for C-peptide and insulin. In 623 consecutively recruited participants, insulin and C-peptide were measured using the Cobas e411 (Roche Diagnostics, Switzerland). Participants with diabetes were excluded (fasting Glucose ≥7.0mmol/L or HbA1c≥6.5%/≥48mmol/L) and reference intervals were calculated with and without the inclusion of persons who were prediabetic, according to two definitions (The World Health Organization (WHO) and American Diabetes Association (ADA)). To ensure the correctness of calibration, the control pools were analyzed by a reference laboratory. The reference intervals were calculated according to the IFCC guidelines, using the RefVal software (Solberg, Oslo, Norway). Comparison of our results with those from the reference laboratory revealed equivalence for C-peptide results whereas the insulin determined on the Cobas e411 assay were 15-20% higher. The difference is attributed to an incorrect conversion factor for converting from activity to metric units. The Cobas e411 assay uses the factor 6.945 for converting from U/mL to pmol/L. This is in disagreement with the biological activity of insulin which is 166.8×10 6 IU/mol or 6.00nmol/IU. We successfully established reference intervals for C-peptide and insulin for non-diabetic and prediabetic participants. The reference intervals for fasting C-peptide and fasting insulin are ready for implementation. A recertification of the insulin standards is needed. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  15. Kinetics of circulating endogenous insulin, C-peptide, and proinsulin in fasting nondiabetic man

    DEFF Research Database (Denmark)

    Henriksen, Jens Henrik Sahl; Tronier, B; Bülow, J B

    1987-01-01

    Plasma concentrations of insulin, C-peptide, and proinsulin were measured in different vascular beds in order to determine renal, hepatic, and systemic kinetics of the endogenous peptides in the fasting condition. Nineteen nondiabetic subjects were studied, two were normal, nine had minor vascular...

  16. Preparation Of Liquid Phase-Double Antibodies Radioimmunoassay For The In Vitro Determination Of Prolactin Hormone In Human Serum

    International Nuclear Information System (INIS)

    MEHANY, N.L.; EL-KOLALY, M.T.; EBEID, N.H.; MEKY, N.H.

    2009-01-01

    In the present study, the preparation of the basic reagents of prolactin (PRL) radioimmunoassay (RIA) technique using liquid phase double antibody with low cost is considered to be the main objective. Three primary components were prepared and characterized to obtain valid and accurate system. These components were polyclonal antibody (anti-PRL), 125 I-prolactin ( 125 I-PRL) radio-iodinated tracer and PRL standards. The production of polyclonal anti-PRL was undertaken by immunizing eight males of white New-Zealand rabbits (two groups) with highly purified PRL antigen through primary injection and five booster doses subcutaneously and intramuscular. The preparation of radio-iodinated ( 1 '2 5 I-PRL) tracer was carried out using chloramine-T method. The preparation of PRL standards were carried out using highly purified PRL antigen in assay buffer. The obtained PRL-antisera were characterized in terms of titer, immuno response and displacement profile. Formulation, optimization and validation of the local liquid phase RIA system were carried out. The results obtained provide a highly sensitive, specific and accurate RIA system of PRL. In conclusion, this technique could be used in diagnosis of pituitary dysfunction such as hyperprolactinaemia and hyperprolactinaemia, prolactinoma, galactorrhoea, amenorrhea and diagnosis of infertility in males and females.

  17. Importance of radioimmunoassay of insulin secretion disorder as atherogenic factor

    International Nuclear Information System (INIS)

    Knyazev, Yu.A.; Bespalova, V.A.; Vakhrusheva, L.L.; Kirbasova, N.P.; Severtseva, V.V.

    1984-01-01

    Using a radioimmunoassay a C-peptide levei was revealed in children, pregnant and lying-in women as well as in patients with insulin-dependent diabetes mellitus. After breakfast and insulin administration wich curative purposes the IRI concentration in children increased whereas the C-peptide level changed insignificantly. Changes of the insulin secretion were more noticeable in severe diabetes mejlitus with vascular complications and in disease decompensation. The atherogenic nature of the lipid metaboiism (an increase in the cholesterol, triglyceride and β-lipoprotein levels), changes in the liver and tendency to vascular involvement are results of insulin effect inadequacy. Such metabolic derangements in pregnant women create unfavorable conditions for the development of fetus and may lead to early atherogenic processes

  18. Solid phase radioimmunoassays

    International Nuclear Information System (INIS)

    Wide, L.

    1977-01-01

    Solid phase coupled antibodies were introduced to facilitate the separation of bound and free labelled ligand in the competitive inhibition radioimmunoassay. Originally, the solid matrix used was in the form of small particles and since then a number of different matrices have been used such as very fine powder particles, gels, paper and plastic discs, magnetic particles and the inside surface of plastic tubes. The coupling of antibodies may be that of a covalent chemical binding, a strong physical adsorbtion, or an immunological binding to a solid phase coupled antigen. New principles of radioimmunoassay such as the solid phase sandwich techniques and the immunoradiometric assay were developped from the use of solid phase coupled antigens and antibodies. The solid phase sandwich techniques are reagent excess methods with a very wide applicability. Several of the different variants of solid phase techniques are suitable for automation. Advantages and disadvantages of solid phase radioimmunoassays when compared with those using soluble reagents are discussed. (orig.) [de

  19. An accurate determination of human grawth hormone content in different pituitary extracts, using a radioimmunoassay with polyacrylamide gel electrophoresis as a bound-free separation system

    International Nuclear Information System (INIS)

    Bartoline, P.; Assis, L.M. de; Scwarz, I.; Pieroni, R.R.

    1977-01-01

    Human growth hormone was extracted and purified according to the method of Roos et al. A first control of its purification and integrity was performed through molecular weight determination by gel filtration on Sephadex G-100 and on plyacrylamide gel electrophoresis (PAGE). Its biological activity was confirmed by the growth promoted in non-hypophysectomized rats at plateau. The main object, however, was the setting up of an accurate, reproducible method that could furnish the more absolute and comparable value of rafioimmunoassayable HGH content in perfect agreement with the results obtained by other laboratories. This was accomplished through a radioimmunoassay system that uses HGH labelled with 125 I, where the separation of the bound from the free antigen is achieved on polyacrylamide gel electrophoresis, by a modification introduced in the original method of Davis. The resulting values, extremely close to that stated by the KABI-Laboratories (Stockolm), through obtained in quite different conditions of incubation, antibody concentration and with no use of second antibody, represent a confident approach to a comparable measure of this hormone in extract, which can also be applied to plasma determinations [pt

  20. Solid phase tube radioimmunoassay for digoxin detection

    International Nuclear Information System (INIS)

    Stellner, K.; Glatz, C.; Linke, R.

    1975-01-01

    A solid phase radioimmunoassay with 125 I is described for cardiac patients. The test for the digoxin determination and the poisoning due to cardiac glycosides can be measured very accurately and carried out easily. In addition, the test determination can be automatically performed in connection with other tests. (GSE/LH) [de

  1. Calcitonin radioimmunoassay: clinical application

    International Nuclear Information System (INIS)

    Raue, F.; Minne, H.; Streibl, W.; Ziegler, R.; Ulm Univ.

    1977-01-01

    A radioimmunoassay for human Calcitonin (hCT) was established: antisera were produced by immunizing goats with synthetic hCT; 7.5 μg hCT were labelled with 1 mCi 125 J; hCT of different quantities in the range between 0.1 to 20 ng/ml served as standard. Separation of free from antibody bound tracer was done using the charcoal procedure. - This RIA-system was sensitive to determine 0.1 ng/ml; the normal range lying below 0.5 ng/ml. This assay was used to study the following clinical problems: 1) in 31 patients, with a thyroid tumor, diagnosis of calcitonin producing medullary thyroid carcinoma was proven. Serum calcitonin of these patients were lying between 1.7 and 120 ng/ml. Clinical signs of this disease are nonspecific, so CT determination is of importance for early diagnosis and control of therapy. In patients with a high tumor risk pentapastrin stimulation of the C-cells reveals calcitonin secretion above normal, if a medullary thyroid carcinoma is present. 2) two patients with pheochromocytoma showed elevated levels of CT before operation; after removal of the tumor serum CT was normalized. Extracts of the adreno-medullary tumor revealed immunoreactive CT corresponding to 4 and 1 ng/ml wet weight. - 3) CT is used for therapy of Paget's disease of the bone, so control of antibody development in the patients is necessary. In 25 patients with Paget's disease no antibody production against the injected hormone was evident. (orig.) [de

  2. Radioimmunoassay in children with glomerulonephritis

    International Nuclear Information System (INIS)

    Ametov, A.S.; Gavryushova, L.P.; Shashinka, M.; Mumladze, Eh.B.; Tvorogova, T.M.; Dakhuk, B.; Dronova, V.I.; Toritsina, D.K.; Petrova, T.V.

    1985-01-01

    Proceeding from a radioimmunoassay of various biologically active substances in the blood and urine (ACTH, cortisol, FSH, LH, prolatin, progesterone, estradiol, plasma renin activity and β 2 -microglobulin) of 220 children with glomerulonephritis change of all indices with relation to the type and gravity of glomerulonephritis as well as renal function was revealed. The nature of influence on corticosteroid and immunosuppressive therapy was shown. The authors consider it appropriate to use the determination of biologically active substances in the blood and urine for a more profound estimation of a child's status

  3. Theoretical and practical application of radioimmunoassays

    International Nuclear Information System (INIS)

    Sokolowski, G.; Wood, W.G.

    1981-01-01

    This book describes experiences made not only in developing and producing commercial reagent kits, but also those made in university research and diagnostic laboratories. The fundamental principles (radioactivity, immunoassay) are explained briefly and tersely. Then the components of the radioimmunoassay are described in detail and illustrated by selected practical examples (production of antibodies, separation of bound and free portions, standards). This chapter is followed by systematic instructions for composing a radioimmunoassay. The actual conditions of the complex problem of quality safety is explained, a field in which particularly the authors are to be regarded as pioneers. Finally an outlook indicates that radioactive alternatives, incorporating the principle of immunologic determinations methods, are available or will be developed for at least a few radioimmunoassays. (orig./MG) [de

  4. Radioimmunoassay of pancreatic glucagon

    International Nuclear Information System (INIS)

    Nooijen, W.J.

    1979-01-01

    The author presents some of the problems and concepts related to the development of a radioimmunoassay of pancreatic glucagon. A specific derivatization of glucagon for raising specific anti-glucagon antisera is introduced, and special procedures for diminishing the non-specific effect are outlined. (G.T.H.)

  5. Radioimmunoassay of norandrosterone

    International Nuclear Information System (INIS)

    Hampl, R.; Starka, L.; Putz, Z.; Protiva, J.

    1983-01-01

    A simple radioimmunoassay of the main nortestosterone metabolite, 3α-hydroxy-5α-estran-17-one (norandrosterone) is described and evaluated. The method employs 3 H-labelled ligand prepared from nortestosterone by three-step synthesis and rabbit antiserum against norandrosterone-17-carboxymethyloxime bovine serumalbumin. (author)

  6. Use of accelerated radioimmunoassay methods for LH, HCG, HPL and α-FP determination in gynecology and obstetrics

    International Nuclear Information System (INIS)

    Grzes, A.

    1976-01-01

    Accelerated methods of determining LH, HCG, HPL and α-FP in clinical practice are discussed. The kinetic determination of LH permits defining ovulation time, the determination of HCG permits early pregnancy ascertainment. The determination of HPL serves the diagnosis of placental functions while α-FP determination in the amniotic fluid may show disorders in the fetal development. (L.O.)

  7. Steroid derivatives and their use in radioimmunoassays

    International Nuclear Information System (INIS)

    Varma, R.K.; Chao, S.T.

    1983-01-01

    Radioimmunoassay techniques have been used to determine the concentration in body fluids of various endogenous and exogenous steroids. In the development of radioimmunoassays for the various steroids, the preparation of an antigen labelled with iodine-125 is of primary concern. The chemical structure of steroids is such that it is generally not possible to radioiodinate them directly. It is necessary to utilize as a precursor of the radiolabeled antigen a derivative of the steroid to be assayed which can be readily iodinatd. The process by which steroids are chosen and structurally modified is given

  8. DNA methylation mediates the effect of maternal cognitive appraisal of a disaster in pregnancy on the child's C-peptide secretion in adolescence: Project Ice Storm.

    Directory of Open Access Journals (Sweden)

    Lei Cao-Lei

    Full Text Available Animal and human studies suggest that prenatal exposure to stress is associated with adverse health outcomes such as type 2 diabetes. Epigenetic modification, such as DNA methylation, is considered one possible underlying mechanism. The 1998 Quebec ice storm provides a unique opportunity to study an independent prenatal stressor on child outcomes. C-peptide is the best measure of endogenous insulin secretion and is widely used in the clinical management of patients with diabetes. The objectives of this study are to determine 1 the extent to which prenatal exposure to disaster-related stress (maternal objective hardship and maternal cognitive appraisal influences children's C-peptide secretion, and 2 whether DNA methylation of diabetes-related genes mediates the effects of prenatal stress on C-peptide secretion. Children's (n = 30 C-peptide secretion in response to an oral glucose tolerance test were assessed in blood at 13½ years. DNA methylation levels of selected type 1 and 2 diabetes-related genes were chosen based upon the genes associated with prenatal maternal objective hardship and/or cognitive appraisal levels. Bootstrapping analyses were performed to determine the mediation effect of DNA methylation. We found that children whose mothers experienced higher objective hardship exhibited higher C-peptide secretion. Cognitive appraisal was not directly associated with C-peptide secretion. DNA methylation of diabetes-related genes had a positive mediation effect of objective hardship on C-peptide secretion: higher objective hardship predicted higher C-peptide secretion through DNA methylation. Negative mediation effects of cognitive appraisal were observed: negative cognitive appraisal predicted higher C-peptide secretion through DNA methylation. However, only one gene, LTA, remained a significant mediator of cognitive appraisal on C-peptide secretion after the conservative Bonferroni multiple corrections. Our findings suggest that DNA

  9. Use of human chorionic gonadtropin and alpha-fetoprotein radioimmunoassays: specificity and apparent half-life determination after delivery and in patients with germ cell tumors

    International Nuclear Information System (INIS)

    Mann, K.; Lamerz, R.; Hellmann, Th.; Kuemper, H.J.; Staehler, G.; Karl, H.J.

    1980-01-01

    The specificity of commercially available hCG and hCG-β antibodies (anti-hCG-β from N.I.A.M.D.D. (SB6), Serono (S), Biosigma (B), Union Carbide (UC) (I.R.E.) and anti-hCG from Union Carbide) were compared. Using 125 I-hCG (CR 115), the crossreactivity with LH (LER 960) was 5.5% for SB6, 0.25% for S and 0.3% for B. In the homologous hCG system UC, crossreactivity was 0.06% with hCG-β and 1.2% with LH, in the hCG-β system UC, it was 2.2% with hCG and 0.01% with LH. Parallel standard curves for hCG, the 2nd I.R.P. hCG and hCG-β were found exclusively with the 125 I-hCG, anti-hCG-β system S. Consequently accurate estimates of the total hCG or hCG-β content in serum and standardization with the 2nd I.R.P. is possible. This system is the most useful for clinical purposes. The serum half-life of hCG was calculated in 10 pregnant women after delivery and was found to be 10 to 34h. AFP half-life time, determined by the double antibody radioimmunoassay was 4.0+-1.8 (+- SD) days in pregnant women after delivery (n=60) and 3.8+-0.9 days in neonates during the first 16 days of life (n=26). Altogether, apparent half-life determinations were carried out in 29 patients with nonseminomatous germ cell tumours. The results indicate that half-life determinations of hCG and AFP may have a predictive value with respect to the monitoring of therapy. (Auth.)

  10. Automation systems for radioimmunoassay

    International Nuclear Information System (INIS)

    Yamasaki, Paul

    1974-01-01

    The application of automation systems for radioimmunoassay (RIA) was discussed. Automated systems could be useful in the second step, of the four basic processes in the course of RIA, i.e., preparation of sample for reaction. There were two types of instrumentation, a semi-automatic pipete, and a fully automated pipete station, both providing for fast and accurate dispensing of the reagent or for the diluting of sample with reagent. Illustrations of the instruments were shown. (Mukohata, S.)

  11. Radioimmunoassay in endocpinology

    International Nuclear Information System (INIS)

    Ametov, A.S.; Torjtsina, L.K.

    1983-01-01

    Radioimmunoassay of the level of various hormones in blood for the diagnosis of thyroid gland diseases, diabetes mellitus, pancreatic gland diseases, adrenal cortex, phophorous-calcium exchange, cerebral-hypophysial deseases, peripheric endocrine glands diseases and others are considered. It is shown that CEA methods implantation in clinical practice permits to obtain a number of new data on mechanism of neurohumoral interrelations of various organs and organism systems

  12. Commercial radioimmunoassay for beta subunit of human chorionic gonadotropin: falsely positive determinations due to elevated serum luteinizing hormone

    International Nuclear Information System (INIS)

    Fowler, J.E. Jr.; Platoff, G.E.; Kubrock, C.A.; Stuzman, R.E.

    1982-01-01

    Among 17 men who had received seemingly curative treatment for unilateral non-seminomatous germ cell tumors for the testis and who had consistently normal serum human chorionic gonadotropin (HCG) levels at a reference laboratory, 7 (41%) had at least one falsely positive commercial serum HCG determination. To investigate the cause of these falsely positive determinations the authors measured the cross reactivity of luteinizing hormone (LH) and follicle stimulating hormone (FSH) standards in the commercial HCG assay, and studied the relationships between commercial HCG levels and serum LH levels, serum FSH levels and gonadal status in men with and without normal gonadal function. The falsely positive HCG determinations appeared to be due to elevated serum LH levels and cross reactivity of LH in the commercial HCG assay because: 1) there was substantial cross reactivity of the LH standards in the commercial assay, 2) the serum LH was elevated in four of six men with solitary testes, 3) there was a striking correlation between elevated serum LH levels and falsely elevated commercial HCG levels in ten men with solitary or absent testes, and 4) there were no falsely positive HCG determinations in 13 normal men but there were falsely positive HCG determinations in seven of ten anorchid men

  13. Radioimmunoassay for the quantitative determination of human anti-meningococcal antibodies. Annual report 1 Feb 78-30 Apr 79

    International Nuclear Information System (INIS)

    Gotschlich, E.C.

    1979-01-01

    During the last year of contract support, we have performed a large number of antibody determinations on sera of children vaccinated with Group A or Group C meningococcal polysaccharide. In addition, a number of sera from monkeys vaccinated with different preparations of Group C were also studied. These sera were provided through the efforts of the staff of NIAID and also from other sources

  14. Application of solid-phase radioimmunoassay in determining antibodies to Aujeszky's disease virus in blood serum of vaccinated pigs

    International Nuclear Information System (INIS)

    Rodak, L.; Smid, B.; Valicek, L.

    1983-01-01

    In the blood sera of pigs vaccinated with inactivated vaccines manufactured by three different manufacturers the RIA method was used to determine the specific antibodies to the virus of Aujeszky's disease. In certain groups of vaccinated pigs the results of the RIA examination are unfavourably affected by the bond of antibodies to the cellular antigenous determinants. This proves that following vaccination antibodies are formed not only against the viral antigen but also against the antigens of cells on which the vaccination virus is propagated. These shortcomings are eliminated by the use of suitable cellular cultures for the preparation of viral and control antigens. Antigens are applicable for RIA and for ELISA examinations of blood sera of infected and vaccinated pigs. The advantages are described of the RIA and ELISA methods as compared with the virus neutralization test. (author)

  15. Early determination of the congenital hypothyroidism by means of the cuantification of STH and T4 by radioimmunoassay method

    International Nuclear Information System (INIS)

    De Penados, R.C.

    1986-11-01

    It was investigated the advantages and disadvantages and conditions of working for the diagnosis of the congenital hypothyroidism by RIA, and its future implementation. It was determined concentration of neonatal STH and neonatal T4 in whole blood of 517 new borns, obtained by capilar punction and recollected in filter paper. 261 samples were found with levels of T4 between normal limits and STH between 0 and 12.5 u U/ml correspond to a normal thyroid function. 29 samples with normal T4 and STH above 30 u U/ml, correspond to a possible primary hypothyroidism. 171 samples with normal T4 and STH between 12.5 and 30 u U/ml were found. (Author)

  16. Correlations between fasting plasma C-peptide, glucagon-stimulated plasma C-peptide, and urinary C-peptide in insulin-treated diabetics

    DEFF Research Database (Denmark)

    Gjessing, H J; Matzen, L E; Frøland, A

    1987-01-01

    This study correlated fasting plasma C-peptide (CP), plasma CP 6 min after stimulation with 1 mg glucagon i.v., and the mean of three 24-h urinary excretions of C-peptide (UCP)/creatinine in 132 insulin-treated diabetics. Patients were divided into three groups: group 1, stimulated CP less than 0.......06 nM (n = 51); group 2, stimulated CP 0.06-0.60 nM (n = 48); and group 3, stimulated CP greater than 0.60 nM (n = 33). In all patients fasting CP was closely correlated to stimulated CP (r = .988, P less than .001), whereas the correlations between UCP and both fasting CP (r = .904, P less than .001......) and stimulated CP r = .902, P less than .001) were slightly less pronounced. The associations between UCP and both fasting CP (r = .716, P less than .001) and stimulated CP (r = .731, P less than .001) were modest in group 2, and even more so in group 3 (r = .557, P less than .001 and r = .641, P less than .001...

  17. Radioimmunoassay for Melatonin

    International Nuclear Information System (INIS)

    Tapp, E.; Skinner, R.G.; Phillips, V.

    1980-01-01

    A radioimmunoassay for melatonin has been developed and used to measure the level of melatonin of male and post-menopausal female patients coming to operation for benign and malignant conditions. The amount of melatonin in the serum of the females was considerably lower than that in males. No difference could be found between patients suffering from benign and malignant conditions. A patient with a non-parenchymatous pineal tumour had considerably lower levels in the serum at three months after surgery and radiotherapy. A further month later melatonin could not be found in samples of serum taken over a 24-hour period. (author)

  18. Radioimmunoassay of bovine growth hormone

    International Nuclear Information System (INIS)

    Dvorak, P.; Becka, S.; Krejci, P.; Chrpova, M.

    1978-01-01

    A radioimmunological method for quantitative determination of bovine growth hormone in blood plasma or serum for routine use was worked out. The antibody is also suitable for radioimmunoassay of bovine growth hormone. The chloramin T and lactoperoxidase methods were used. Standard b-STH isolated by one of the authors was labelled with I-125(Na 125 I, carrier free, Amersham). The I-125-hormone was separated on Sephadex G-50 or G-100 and stored in 0.05M phosphate pH 7.5 with 1% of human serum albumine at 25 deg C. The method was checked on 2500 samples. Rabbit antiserum to b-STH was prepared in sufficient amount to serve also for other laboratories interested in the method. (author)

  19. Simultaneous radioimmunoassay for luteinizing hormone and prolactin

    International Nuclear Information System (INIS)

    Steele, M.K.; Deschepper, C.F.

    1985-01-01

    A combined radioimmunoassay (RIA) for the measurement of the anterior pituitary proteins luteinizing hormone (LH) and prolactin (PRL) is described and compared with individual RIAs for these hormones. The standard curves and the sample values for LH and PRL were identical when determined in a combined or in an individual RIA. This technique may prove useful to a number of laboratories where it is desirable to determine levels of more than one hormone in limited sample volumes

  20. Elevation of plasma gonadotropin concentration in response to mammalian gonadotropin releasing hormone (GRH) treatment of the male brown trout as determined by radioimmunoassay

    International Nuclear Information System (INIS)

    Crim, L.W.; Cluett, D.M.

    1974-01-01

    Rapid increase of the plasma gonadotropin concentration as measured by radioimmunoassay has been demonstrated in response to GRH treatment of the sexually mature male brown trout. Peak gonadotropin values were observed within 15 minutes of GRH treatment, however, the return to baseline values was prolonged compared with the mammalian response. These data support the concept that the brain, operating via releasing hormones, plays a role in the control of pituitary hormone secretion in fish

  1. Ethnic differences in C-peptide levels and anti-GAD antibodies in South African patients with diabetic ketoacidosis

    NARCIS (Netherlands)

    Rheeder, P; Stolk, RP; Grobbee, DE

    To determine differences between Black and White South Africans with diabetic ketoacidosis (DKA) and between Black patients on insulin vs. those on oral agents presenting with DKA, post stabilization fasting C-peptide levels and anti-glutamic acid decarboxylase (GAD) antibodies were measured

  2. A solid-phase radioimmunoassay for detection of tetanus antibodies

    International Nuclear Information System (INIS)

    Dow, B.C.; Barr, A.; Crawford, R.J.; Mitchell, R.

    1983-01-01

    A solid-phase radioimmunoassay has been developed as a screening technique for tetanus antibodies in blood plasma. It is based on the principle of a commercial test for Hepatitis B antibody. Compared to previous screening techniques, the radioimmunoassay showed better stability with no apparent loss of sensitivity over a 2 month period. This technique has proved useful in determining tetanus immunity and in monitoring free antibody level in treated cases of clinical tetanus. (U.K.)

  3. Radioimmunoassay of platelet proteins

    International Nuclear Information System (INIS)

    Pepper, D.S.

    1987-01-01

    The radioimmunoassay of platelet-specific proteins has proven to be an excellent way of monitoring platelet activation in vivo. In contrast to earlier methods such as aggregometry, which has been the major tool used in the evaluation of antiplatelet drugs, the RIAs are capable of working with samples which have been subjected to physiological conditions such as haematocrit, oxygen tension, shear rate and ionized calcium concentration. Also, in contrast to aggregometry, no choice of agonist is necessary. Thus, for the first time it has been possible to monitor the effects of therapeutic intervention with drugs upon the platelet release reaction in vivo. It seems reasonable to equate the release reaction in vivo with activation in vivo, though the stimuli necessarily remain unknown. Nevertheless, the fact that a significant number of the compounds mentioned in Table 3 are indeed capable of reducing platelet activation in vivo and that this effect can be measured objectively is a major step forward in our understanding of platelet pharmacology. Two important goals remain to be achieved, however, the establishment of nonhuman animal models for the evaluation of newer compounds in vivo and longer-term goal of proving in the clinical setting the relevance or otherwise of platelet activation per se to the clinical outcome of a particular disease. In this respect, the availability of accurate, reliable and specific radioimmunoassays has a central role

  4. Radioimmunoassay of steroid hormone

    International Nuclear Information System (INIS)

    Murakami, Tadashi

    1975-01-01

    Low acid pepsin treated gamma-globulin was applied to ammonium sulfate salting out method, which was a method to separate bound fraction from free one in radioimmunoassay of steroid hormone, and the effect of the separation and the standard curve were examined. Pepsin treated gamma-globulin was prepared in pH 1.5 to 5.5 and then the pepsin was completely removed. It had an effect to accelerate the precipitation in radioimmunoassay of steroid hormone labelled with 3 H. The effect of pepsin treated gamma-globulin to adhere free steroid hormone and to slat out bound one was compared with that of human gamma-globulin. Pepsin treated gamma-globulin, which was water soluble, could easier reach its optimal concentration, and the separation effect was better than human gamma-globulin. The standard curve of it was steeper, particularly in a small dose, and the reproducibility was also better. It could be applied not only to aldosterone and DOC, but also to the steroid hormones, such as progesterone and DHEA, and it seemed suitable for routine measurement method. (Kanao, N.)

  5. Development and standardization of radioimmunoassay technique for human proinsulin determining and its use in the study of type II diabetes mellitus associated to obesity; Desenvolvimento e padronizacao da tecnica de radioimunoensaio para a determinacao de pro-insulina humana e sua aplicacao no estudo do diabetes mellitus tipo II associado a obesidade

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento, Martha do

    1996-12-31

    The availability of immunoassay methodology for proinsulin is important to define its physiological and pathophysiological significance in humans. Serum concentration of proinsulin are elevated in patients with type II Diabetes Mellitus (NIDDM) and recently diagnosed Type I, so a raised circulating concentration of proinsulin may serve as an early indicator of {beta} cells dysfunction. recently, in NIDDM the serum concentrations of proinsulin and its B-chain-C-peptide junctional split form, des (31-32), were found to correlate with diastolic blood pressure, a risk factor for cardiovascular disease. The development of a sensitive and specific radioimmunoassay (RIA) methodology for proinsulin has been difficult due to its low concentration in serum and the presence of proinsulin conversion intermediates in fluids and tissues. Also other potentially cross-reactive peptides, including insulin and C-peptide, can interfere in the assay. This work describe a highly specific human proinsulin RIA developed by using biosynthetic human proinsulin (hPI) as immunogen, standard and tracer. (author) 133 refs., 17 figs., 36 tabs.

  6. A Study of the Insulin and the C-Peptide Responses to Oral Glucose Load in Nondiabetic and Diabetic Subjects

    International Nuclear Information System (INIS)

    Lee, Myung Chul; Choi, Sung Jae; Kim, Eung Jin; Koh, Chang Soon; Min, Hun Ki

    1977-01-01

    The present study was undertaken to evaluate the significance of the insulin and the C-peptide response to oral glucose loads in normal and diabetic subjects and to establish the effects of the obesity. In this study, the authors have measured plasma insulin and C-peptide by means of radioimmunoassay in 10 nonobese normal, 5 obese normal, 13 nonobese moderate diabetic patients, 9 obese moderate diabetic patients and 9 severe diabetic patients. The results obtained were as follows; 1) In 10 nonobese normal subjects, the plasma insulin level at fasting state and at 30, 60, 90, and 120 min after oral glucose loads were 15.7±3.4, 48.3±9.8, 40.4±6.7, 37.4±6.5 and 26.0±4.2 uU/ml (Mean±S.E.) and C-peptide were 1.9±0.3, 3.9±0.6, 6.3±0.6, 5.7±0.5 and 4.0±0.5 ng/ml. The change of C-peptide was found to go almost parallel with that of insulin and the insulin value reaches to the highest level at 30 min whereas C-peptide reaches to its peak at 60 min.. 2) The plasma insulin level in 5 obese normal subjects were 38.9±12.3, 59.5±12.3, 59.2±17.1, 56.1±20.0 and 48.4±17.2 uU/ml and the C-peptide were 5.5±0.4, 6.8±0.5, 7.9±0.8, 7.9±0.8 and 7.8±2.0 ng/ml. The insulin response appeared to be greater than nonobese normal subjects. 3) In 13 nonobese moderate diabetic patients, the plasma insulin levels were 27.1±4.9, 44.1±6.0, 37.3±6.6, 35.5±8.1 and 34.7±10.7 uU/ml and the C-peptide levels were 2.7±0.4, 4.9±0.7, 6.5±0.5, 7.0±0.3 and 6.7±1.0 ng/ml. There was little significance compared to nonobese normal groups but delayed pattern is noted. 4) In 9 obese moderated diabetic patients, the plasma insulin levels were 22.1±7.9, 80.0±19.3, 108.0±27.0, 62.0±17.6 and 55.5±10.l uU/ml and the C-peptide levels were 5.2±0.4, 8.0±1.0, 10.4±1.6, 10.4±1.7 and 10.1±1.0 ng/ml and its response was also greater than that of nonobese moderate diabetic patients. 5) The plasma insulin concentrations in 9 severe diabetic subjects were 8.0±3.8, 12.1±3.5, 16.8±4.6, 19

  7. Radioimmunoassay to quantitatively measure cell surface immunoglobulins

    International Nuclear Information System (INIS)

    Krishman, E.C.; Jewell, W.R.

    1975-01-01

    A radioimmunoassay techniques developed to quantitatively measure the presence of immunoglobulins on the surface of cells, is described. The amount of immunoglobulins found on different tumor cells varied from 200 to 1140 ng/10 6 cells. Determination of immunoglobulins on the peripheral lymphocytes obtained from different cancer patients varied between 340 to 1040 ng/10 6 cells. Cultured tumor cells, on the other hand, were found to contain negligible quantities of human IgG [pt

  8. Radioimmunoassays - what is their diagnostic value

    International Nuclear Information System (INIS)

    Panitz, N.

    1983-01-01

    A selection is made of hormones and enzymes which are measurable by radioimmunoassay and their organ-specific function is described. Endocrine function tests together with the stimulating or suppressing substances, reaction in the organism and the examined regulation are listed. Non-radioactive immunological determination methods and the use of monoclonal antibodies in vitro and in vivo with ''tumor imaging'' are indicated. (orig.) [de

  9. Radioimmunoassay for serum paraquat

    International Nuclear Information System (INIS)

    Fatori, D.; Hunter, W.M.

    1980-01-01

    Two variants of a radioimmunoassay for the bipyridylium herbicide Paraquat are described. Both employ antiserum raised to Paraquat-BSA which has been covalently linked to particulate solid-phase support media. The rapid assay for clinical use employs a [ 3 H] Paraquat tracer, requires no agitation and yields results in the range 10-2500 ng/ml serum in 20 min from receipt of sample. The more sensitive assay, designed for research purposes, employs a 125 iodinated tracer, requires 2 h continuous agitation but can detect Paraquat at 0.1 ng/ml in simple aqueous solution or 0.25 ng/ml serum. Results from rapid clinical assay agree well with the existing colorimetric method. (Auth.)

  10. Association between physical activity and serum C-peptide levels among the elderly.

    Science.gov (United States)

    Li, Ying; Meng, Lu; Miao, QianQian; Sato, Yasuto

    2014-07-01

    Serum C-peptide is an active peptide that has important physiological functions and characteristics in the elderly. The present study aimed to investigate the association between physical activity and serum C-peptide level independent of insulin level among the elderly. The study included 1700 elderly participants aged ≥ 65 years. Stratified analysis of covariance was used to compare serum C-peptide levels in participants with different physical activity levels. Two separate multiple linear regression models were created to estimate the association between physical activity and serum C-peptide level. The results of analysis of covariance stratified by sex, body mass index and serum insulin level showed that those who engaged in vigorous physical activity had lower serum C-peptide levels than those who engaged in light or no physical activity. Separate multiple linear regression analysis showed that in those with low serum C-peptide levels (≤ 0.621 nmol/L), physical activity was significantly positively associated with the serum C-peptide level. In contrast, physical activity was negatively associated with the serum C-peptide level among those with serum C-peptide level >0.621 nmol/L. The serum C-peptide level showed a significant two-way association with physical activity. The present findings suggest that physical activity modification is important for improving serum C-peptide levels among the elderly. © 2013 Japan Geriatrics Society.

  11. Radioimmunoassay of parathormone in human blood serum

    International Nuclear Information System (INIS)

    Leicht, E.

    1982-01-01

    A radioimmunoassay for immune reactive PTH in human blood serum has been developed and optimized. The method described is capable of largely safely discriminating increased PTH concentrations from normal values. For the group of patients suffering from hypoparathyroidism, the PTH values in the blood serum have been found to be generally lower, but quite an overlapping of lower values and values at the lower normal limit has been stated at the same time. Subsequent to an oral administration of phosphate in an acute experiment, so following a calcium-deficient diet taken over 24 hours, an increase in immune reactive PTH in the serum could be detected. The part of this thesis dealing with the method of treatment thoroughly discussed the various steps of optimization of the assay on the basis of extensive experimental data collected by the author. It presents a detailed assessment of current knowledge on, efficiency of and problems involved in PTH determination by radioimmunoassay. (orig./MG) [de

  12. Ethnic differences in C-peptide levels and anti-GAD antibodies in South African patients with diabetic ketoacidosis.

    Science.gov (United States)

    Rheeder, P; Stolk, R P; Grobbee, D E

    2001-01-01

    To determine differences between Black and White South Africans with diabetic ketoacidosis (DKA) and between Black patients on insulin vs. those on oral agents presenting with DKA, post stabilization fasting C-peptide levels and anti-glutamic acid decarboxylase (GAD) antibodies were measured together with serum glucose, acid base and urine ketones on admission. Of 60 patients with diabetic ketoacidosis (DKA) (76 admissions), the 43 Black patients had a higher BMI (23.1 vs. 20.0 kg/m(2), p=0.05) than did the 17 White patients, were more often newly diagnosed (37% vs. 1%, p=0.03), and a greater proportion of Black patients had fasting C-peptide levels >0.3 nmol/l (28% (10/36) vs. 0%, p=0.03). Of these 10 Black patients, eight were anti-GAD-negative. Thirteen Black patients (33%) were anti-GAD-positive vs. 10 (67%) White patients (p=0.03). There was no statistically significant difference in anti-GAD positivity between Black patients on oral agents or those on insulin. Most patients (5/7) admitted on oral agents had negative C-peptide levels after stabilization. Our results suggest that in patients presenting with DKA, a quarter of Black South Africans have C-peptide levels regarded as being indicative of type 2 DM and are less frequently anti-GAD-antibody-positive than are White South Africans.

  13. A radioimmunoassay for chicken avidin

    International Nuclear Information System (INIS)

    Kulomaa, M.S.; Elo, H.A.; Tuohimaa, P.J.

    1978-01-01

    A double-antibody solid-phase radioimmunoassay for chicken avidin is reported. Avidin was labelled with 125 I by the chloramine-T method. The bound and free avidin were separated with a second antibody bound to a solid matrix. In the logit-log scale the standard curve was linear from 1-2 to 100-200ng of avidin/ml. Cross-reaction of ovalbumin was less than 0.015%. Saturation of biotin-binding sites of avidin with an excess of biotin decreased radioimmunoassay values by about 15%. Recovery studies indicated that avidin can be assayed from all chicken tissues studied with radioimmunoassay, whereas the [ 14 C]biotin/bentonite method gave poor recoveries for avidin in the liver and kidney. Radioimmunoassay and the [ 14 C]biotin/bentonite method gave similar concentrations for oviduct avidin. (author)

  14. Clinical indications of prolactin radioimmunoassay

    International Nuclear Information System (INIS)

    Lengyel, A.M.J.; Vieira, J.G.H.; Zanella, M.R.; Zampieri, M.; Chacra, A.R.

    1980-01-01

    Is a review is presented of the main clinical uses of prolactin measurements, including the galactorrhea-amenorrhea syndrome, an experiment employing the prolactin radioimmunoassay is related. (Author) [pt

  15. C-peptide increases Na,K-ATPase expression via PKC- and MAP kinase-dependent activation of transcription factor ZEB in human renal tubular cells.

    Directory of Open Access Journals (Sweden)

    Dana Galuska

    Full Text Available Replacement of proinsulin C-peptide in type 1 diabetes ameliorates nerve and kidney dysfunction, conditions which are associated with a decrease in Na,K-ATPase activity. We determined the molecular mechanism by which long term exposure to C-peptide stimulates Na,K-ATPase expression and activity in primary human renal tubular cells (HRTC in control and hyperglycemic conditions.HRTC were cultured from the outer cortex obtained from patients undergoing elective nephrectomy. Ouabain-sensitive rubidium ((86Rb(+ uptake and Na,K-ATPase activity were determined. Abundance of Na,K-ATPase was determined by Western blotting in intact cells or isolated basolateral membranes (BLM. DNA binding activity was determined by electrical mobility shift assay (EMSA. Culturing of HRTCs for 5 days with 1 nM, but not 10 nM of human C-peptide leads to increase in Na,K-ATPase α(1-subunit protein expression, accompanied with increase in (86Rb(+ uptake, both in normal- and hyperglycemic conditions. Na,K-ATPase α(1-subunit expression and Na,K-ATPase activity were reduced in BLM isolated from cells cultured in presence of high glucose. Exposure to1 nM, but not 10 nM of C-peptide increased PKCε phosphorylation as well as phosphorylation and abundance of nuclear ERK1/2 regardless of glucose concentration. Exposure to 1 nM of C-peptide increased DNA binding activity of transcription factor ZEB (AREB6, concomitant with Na,K-ATPase α(1-subunit mRNA expression. Effects of 1 nM C-peptide on Na,K-ATPase α(1-subunit expression and/or ZEB DNA binding activity in HRTC were abolished by incubation with PKC or MEK1/2 inhibitors and ZEB siRNA silencing.Despite activation of ERK1/2 and PKC by hyperglycemia, a distinct pool of PKCs and ERK1/2 is involved in regulation of Na,K-ATPase expression and activity by C-peptide. Most likely C-peptide stimulates sodium pump expression via activation of ZEB, a transcription factor that has not been previously implicated in C-peptide

  16. Radioimmunoassay of measles virus hemagglutinin protein G

    Energy Technology Data Exchange (ETDEWEB)

    Lund, G.A.; Salmi, A.A. (Turku Univ. (Finland))

    1982-08-01

    Guinea pig and rabbit antisera from animals immunized with purified measles virus hemagglutinin (G) protein were used to establish a solid-phase four-layer radioimmunoassay for quantitative measurement of the G protein. The sensitivity of the assay was 2 ng of purified G protein, and 200 ..mu..g of protein from uninfected Vero cells neither decreased the sensitivity nor reacted non-specifically in the assay. Radioimmunoassay standard dose-response curves were established and unknown values interpolated from these using the logit program of a desktop computer. Using this procedure, a measles virus growth curve in infected Vero cells was determined by measurement of G protein production. Under these same conditions, hemagglutination was not sensitive enough to detect early hemagglutinin production. Viral antigens in canine distemper virus, Newcastle disease virus, parainfluenza viruses 1-4, simian virus 5, and respiratory syncytial virus-infected cell lysates did not cross-react in the radioimmunoassay. A small degree of cross-reactivity was detected with mumps viral antigens, both with Vero cell-derived (wild-type strain) and egg-derived (Enders strain) purified virus preparations and with a cell lysate antigen prepared from wild-type mumps virus-infected Vero cells.

  17. Radioimmunoassay of triiodothyronine in urine

    International Nuclear Information System (INIS)

    Kosowicz, J.; Gembicki, M.; Schneider, E.; Eder, M.

    1977-01-01

    In 21 cases of hypothyroidism, in 39 cases of hyperthyroidism, in 54 healthy subjects, in 23 pregnant women, and in certain internal diseases determinations of triiodothyronine were carried out in urine by radioimmunoassay. Anti-T 3 antibodies were obtained in rabbits and sheep immunized with a complex of bovine albumin with triiodothyronine ester. Labelled triiodothyronine of high specific activity was obtained by iodinating triodothyronine by the chloramine method. Determinations of triiodothyronine were performed in morning urine and the obtained values were calculated for one-hour excretion. In healthy subjects the excretion of T 3 was from 20 to 95 ng/hour, in hyperthyroidism it was significantly raised to from 120 to over 600 ng/hour, while in most cases of hypothyroidism it was decreased. In pregnancy the urinary excretion of T 3 was normal amounting to from 34 to 87 ng/hour, although in most cases the serum T 3 concentration was raised. In cases of anorexia nervosa and in obese starving subjects the excretion of T 3 fell significantly, and similarly low excretion was found in some cases of debilitating diseases and myocardial infarction. (author)

  18. Type-specific IgG and IgA antibodies in old lymphogranuloma venerum determined by solid-phase radioimmunoassay

    Energy Technology Data Exchange (ETDEWEB)

    Meurman, O.; Terho, P.; Sonck, C.E.

    1981-01-01

    A solid-phase radioimmunoassay (RIA) using egg-grown purified Chlamydia trachomatis lymphogranuloma venereum (LGV) serotypes L1, L2, and L3 as antigen was used to measure type-specific IgG and IgA antibodies in sera of 36 patients who had contracted LGV infection about 40 years ago. The RIA test gave compatible results with the standard microimmunofluorescence test, and by RIA it was possible to identify the infecting serotype in 30 out of 36 patients studied. In 28 cases this was L2 and in two cases L1. Each patient had IgG antibodies and most of them (80%) IgA antibodies to at least one of the LGV serotypes. The antibody titers were still high 40 years after the acute infection, being higher than in male patients with a recent chlamydial urethritis. Highest antibody titers were detected in LGV patients who had a severe disease with intestinal involvement.

  19. Radioimmunoassay of human urinary kallikrein

    International Nuclear Information System (INIS)

    Goering, W.

    1980-01-01

    Using a human urinary kallikrein, purified by means of Trasylol sepharose, it has been possible to develop a radioimmunoassay of kallikrein capable of detecting the substance down to a concentration of 0.5 ng/ml. The specific activity of the tracer labelled with 125-iodine using the Chloramine-T method was 30-70 nCi/ng of kallikrein. The antiserum titres for the antikallikrein serum were 1:20.000 up to 1:50.000. Human urine, submandibular and parotid salivae as well as pancreatic secretion in this RIA reacted in the same manner as the kallikrein standard solution. The kallikrein content in urine, as determined by the RIA was between 0 and 300 ng/ml, in the saliva between 400 and 2.000 ng/ml, and in the pancreatic juice between 300 and 12.000 ng/ml. Using human serum, only an incomplete immunological cross-reaction could be achieved. In human liquor as well as in animal preparation, no cross-reacting substances could be detected. (orig.) [de

  20. Radioimmunoassay of polypeptide hormones and enzymes

    International Nuclear Information System (INIS)

    Felber, J.P.

    1974-01-01

    General principles of radioimmunoassay are reviewed. Detailed procedures are reviewed for the following hormones: insulin, pituitary hormones, gonadotropins, parathyroid hormone, ACTH, glucagon, gastrin, and peptide hormones. Radioimmunoassay of enzymes is also discussed. (U.S.)

  1. Radioimmunoassay for rhesus monkey gonadotropins

    International Nuclear Information System (INIS)

    Faiman, C.; Stearns, E.L.; Winter, J.S.D.; Reyes, F.I.; Hobson, W.C.

    1975-01-01

    Heterologous double-antibody radioimmunoassay methods are described for the measurement of circulating levels of rhesus monkey (Macaca mulatta) FSH and LH; the latter assay is also applicable to rhesus chorionic gonadotropin (CG) estimations. The FSH assay utilizes purified rat FSH for trace, either of two anti-human FSH antisera and a semipurified rhesus pituitary standard. The LH assay utilizes purified ovine LH for trace, an anti-human CG antiserum and the same rhesus pituitary standard. The use of these systems obviates the necessity of purifying rhesus gonadotropins which are required for the development of homologous radioimmunoassay systems. (U.S.)

  2. Radioimmunoassay of Human Chorionic Gonodotropin

    International Nuclear Information System (INIS)

    Majali, M.A.; Shah, K.B.; Mani, R.S.

    1981-01-01

    A rapid and sensitive radioimmunoassay has been developed for the measurement of Human Chorionic Gonadotropin (HCG) in serum. Human chorionic gonadotropin has been labelled with 125 I to attain a specific activity between 80-120 μCi/μg. Aqueous dioxane (74 vol.%) has been employed to separate the bound and freehormone in the radioimmunoassay. The sensitivity of this technique has been found to be approximately 1.5 mIU/ml of HCG. The intra assay variation has been found to be less than 5% and inter assay variation has been found to be less than 12%. (author)

  3. Recent advances in steroid radioimmunoassay

    International Nuclear Information System (INIS)

    Jeffcoate, S.L.

    1977-01-01

    The advances since 1974 in the techniques of measuring steroid molecules by radioimmunoassay are reviewed in this paper. They are considered under the following headings: preparation and use of antisera; preparation and use of tracers; preparation of biological samples before assay; dispensing of the reagents in the assay; separation of free and bound radioactivity; counting and data processing; quality control and standardization. (orig.) [de

  4. Problems in radioimmunoassay of human lutropin with commercially available regents

    International Nuclear Information System (INIS)

    Hammond, J.E.; Phillips, J.C.; Straight, C.B.; Hammond, M.G.

    1980-01-01

    To evaluate five commercially available reagent sets supplied for the radioimmunoassay of lutropin, we determined whether there was parallelism between the curve given by dilutions of the standards supplied by the manufacturers, by dilutions of a serum pool, and by dilutions of a standard preparation from human pituitaries, LER-907. These studies demonstrated significant analytical problems with three of the five sets. We conclude that each user should carefully evaluate all commercially available radioimmunoassays for lutropin (and, by inference, for other peptide hormones) before use

  5. Quality control of radioiodinated gastrin for radioimmunoassay

    International Nuclear Information System (INIS)

    Ginabreda, M.G.P.; Borghi, V.C.; Bettarello, A.

    1988-07-01

    Radioiodinated human gastrin has been prepared at IPEN laboratory for radioimmunoassay use. This work developed the quality control of this tracer analyzing parameters of the labelling reaction, chromatographic purification and radioimmunoassay. The radioiodination yield obtained in five experiments was reproducible and similar when analyzed on 7% polyaraylamide gel eletrophoresis - PAGE - (mean + - SD of 51.70 + - 10.76%) and by1 25 I incorporation checked through thrichloroacetic acid precipitation - TCA - (57-36 + - 9.69%). Similary, after purification the labelled gastrin revaled high and reproducible purity degree when submitted to PAGE (96.57 + - 1.06%) and CA (94.82 + - 4.20%) analysis. The respective specific activities varied from 62 to 307 uCi/ug, being determined by the self-displacement method, which is based on the immunoactivity of the tracer. In this way, the antibody titers required to bind 50% of the tracer ranged from 1:32.000 to 1:180.000. Consequently, the respective doses producing 50% fall in the maximum response of the radioimmunoassays ranged from 155.0 to 24.0 pmol/1, but remained unchanged for each tracer even after three months of its preparations. The tracers presented very low non-specific binding values (1.78 + - 0.79%), stablespecific binding values (46.49 + - 5.65%) and a good between-assay precision, evaluated by an internal quality control sample (25.71 + - 4.30%) with coefficient of variation of 16.74%). The PAGE analysis of the unlabeled gastrin used in the first and last radioiodination revealed an unique and unaltered component, confirming the quality of the tracers. (author) [pt

  6. Influence of molecular weight of DNA on the determination of anti-DNA antibodies in systemic lupus erythematosus (SLE) sera by radioimmunoassay

    Energy Technology Data Exchange (ETDEWEB)

    Geisert, M.; Heicke, B.; Metzmann, E.; Zahn, R.K.

    1975-04-01

    Using a radioimmunoassay (RIA) based on the Farr technique with radioactively labeled /sup 3/H-DNA for quantitative measurements of anti-DNA antibodies in sera of patients with systemic lupus erythematosus (SLE), the influence of molecular weight of DNA (ranging from 0.1 x 10/sup 6/ to 22.0 x 10/sup 6/ daltons) on binding and precipitation in this system has been investigated. Comparing our results with mathematical models it follows that one antibody molecule is fixed on the average to a statistical DNA segment of 2 x 10/sup 6/ to 4 x 10/sup 6/ daltons. Furthermore binding capacity of the DNA was found to be independent of the molecular weight, as demonstrated in a double label experiment using /sup 14/C and /sup 3/H-labeled DNA of different size. However, the amount of radioactivity precipitated was found to depend on the molecular weight of the labeled DNA following a non-linear function. It was calculated that a minimal ratio of fixed antibody molecules per a certain size of DNA was necessary for precipitation. The mathematical treatment of the observed non-linear precipitation dependence will be discussed using various statistical models. The results indicate that the quantitative measurements of anti-DNA antibodies with the Farr technique e.g., for diagnosis and control of SLE in clinical immunology is highly dependent on the molecular weight of the labeled DNA used in the assay system and reliable results are only obtained with DNA of a sufficiently high molecular weight. (auth)

  7. A radioimmunoassay for anti-virus antibodies in farm animals

    International Nuclear Information System (INIS)

    Rodak, L.; Smid, B.; Sedlacek, M.

    1978-01-01

    A radioimmunoassay for determination of antibodies to Aujeszky's disease virus in piq serum is described. The results show a number of advantaqes of this method over the routinely employed virus-neutralization test. The possibility of using the RIA method in diagnosing other viral diseases of farm animals is suggested. (authors)

  8. Association between low C-peptide and fragility fractures in postmenopausal women without diabetes.

    Science.gov (United States)

    Ferro, Y; Russo, C; Russo, D; Gazzaruso, C; Coppola, A; Gallotti, P; Zambianchi, V; Fodaro, M; Romeo, S; Galliera, E; Marazzi, M G; Romanelli, M M C; Giannini, S; Pujia, A; Montalcini, T

    2017-10-01

    C-peptide has been shown to exert several, previously unknown, biological effects. A recent cross-sectional study demonstrated an association between low C-peptide serum levels and low lumbar bone density of postmenopausal women not affected by diabetes. To date, very little research attention has been directed toward the association between C-peptide and osteoporotic fractures. To contribute toward filling this gap, we investigated the association between C-peptide and fractures in postmenopausal women. A cohort of 133 non-diabetic postmenopausal women with and without a history of fractures was evaluated in this cross-sectional investigation. Standardized interviews were performed to gather information on the patients' fracture history. All of the participants underwent a bone mineral density assessment by DXA, radiographs, and a serum C-peptide measurement. Thirty-four women presented fractures. Bivariate analysis revealed an inverse correlation between C-peptide and fractures (r = -0.27, p = 0.002). A significant difference in mean C-peptide levels was also found between women with vs. without fractures (p = 0.01, adjusted for age, BMI and glucose). Logistic regression analysis showed that C-peptide levels, femoral and vertebral BMD were all negatively associated with fracture status (B = -1.097, ES = 0.401, p = 0.006, 95% CI 0.15-0.73; B = -15.6, SE = 4.17, p C-peptide levels and a history of fractures in postmenopausal women without diabetes. These results suggest that C-peptidemay exert an effect on bone mineral density. However, further large-scale studies are needed to corroborate this finding and investigate the potential underlying mechanisms involved.

  9. Homologous radioimmunoassay of human prolactin

    International Nuclear Information System (INIS)

    Felixberger, F.X.

    1980-01-01

    Gelfiltration on Sephadex G-75 showed a heterogenity of prolactin in serum of patients with prolactinoma and in culture medium of a prolactinoma. Serum of patients with prolactinoma and culture medium of a prolactinoma were examined as possible sources of prolactin by gel filtration and ion exchange chromatography. Polyacrylamide electrophoresis revealed both preparations as contaminated by other proteins. Nevertheless prolactin isolated form culture medium of a prolactinoma is good enough as a tracer in our radioimmunoassay because contaminating proteins in this preparation do not inferfere in our system. An hPRL antiserum created in a rabbit against a crude fraction of human serum of a patient with prolactinoma was tested by titration, saturation studies, and ion exchange chromatography. In comparison with lactoperoxidase-iodinated prolactin Chloramine T iodinated prolactin showed higher loss of immunochemical properity, however higher specific activity. Specifity and precision in our radioimmunoassay system were described and the conditions of optimal sensitivity in our assay were evaluated. (orig.) [de

  10. Homologous radioimmunoassay for human prolactin

    International Nuclear Information System (INIS)

    Reuter, A.M.; Kennes, F.; Gevaert, Y.; Franchimont, P.

    1976-01-01

    Although thee are descriptions of a range of radioimmunoassays for human prolactin in various biological fluids, only one of these is an homologous assay using human prolactin as the reference standard and tracer as well and an anti-human prolactin antiserum (Sinha, Y.N., Selby, F.W.; Lewis, U.; and Vanderlaan, W.P., 1973, J. Clin. Endocr., Vol. 36, 509). A homologous radioimmunoassay using human putuitary prolactin has been developed. The separation method is based on the double antibody solid phase system. Cross reactivity with human growth hormone (GH), placental lactogen (HPL), the pituitary protein hormones and prolactins of various species were studied as were values found in normal subjects in basal conditions and after a TRH injection. (author)

  11. Solid phase radioimmunoassay

    International Nuclear Information System (INIS)

    Vann, W.P.; Yaverbaum, S.

    1976-01-01

    Method of determining the concentration of a substance in a solution which comprises the steps of incubating the solution with a known amount of radioactively labelled substance and a suspendable composite consisting of anti-substance antibody coupled chemically through an intermediate silane coupling agent to an inorganic carrier, the incubation period being for a time sufficient to form immunochemical complexes, separating the complexes from the solution, determining the radioactivity of either the separated complexes or the remaining solution, and relating that determination to a standard curve. Specific assays for digoxin, insulin, and estriol are disclosed. 9 claims, 5 drawing figures

  12. 21 CFR 862.1135 - C-peptides of proinsulin test system.

    Science.gov (United States)

    2010-04-01

    .... Measurements of C-peptides of proinsulin are used in the diagnosis and treatment of patients with abnormal insulin secretion, including diabetes mellitus. (b) Classification. Class I (general controls). The device...

  13. Radioimmunoassay of luteinizing hormone in hypothyroidism

    International Nuclear Information System (INIS)

    Sobieszczyk, S.

    1975-01-01

    Radioimmunoassay of luteinizing hormone was performed in 18 women with primary hypothyroidism and 15 women with secondary hypothyroidism. The results of determinations were compared with LH values found in healthy women at reproductive age and after menopause. It was observed that in primary hypothyroidism the level of LH is normal, in young women it was from 6 to 25 m IU/ml, while in the postmenopausal period it increased to 70 to 200 m IU/ml. In secondary hypothyroidism due to pituitary hypofunction the LH level is undetectable or lies in the range of lowest values observed in healthy subjects, not exceeding 8 m IU/ml. Determinations of serum LH may be useful for differential diagnosis of primary and secondary hypothyroidism. (author)

  14. Development of a radioimmunoassay of tetracycline and its derivatives

    International Nuclear Information System (INIS)

    Zitzewitz, A. von.

    1981-01-01

    A radioimmunoassay for tetracycline was developed in the context of the present work. The determination of tetracycline content in biological samples is to be made valid using tetracycline RIA. As well as the carbodiimide method, a by radioimmunologists extremely seldomly used way involving a condensation reaction between protein and haptene via the Mannich reaction was successfully applied. Antibodies were produced using a conventional immunisation method after Abraham, the other applied alternative method after Vaitukaitis et al. The general working methods had to be adapted to the tetracycline RIA. All variable parameters of the antigen-antibody bond were tested to optimize the incubation conditions of the system as well as to control the tracer for a degradation. The detection limit of RIA is 10 - 12 , the measuring range from 10 - 12 to 10 - 10 mol for tetracycline hydrochloride and rolitetracycline respectively and up to 10 - 9 mol for its derivates. The investigations for cross reactions showed a high specificity for tetracycline (100%) and its intravenously appliable pyrrolidino-methyl derivative rolitetracycline (88%). Standard curves could be drawn up using either of the two compounds tetracycline and rolitetracycline as standard. The pharmaco-kinetic behaviour of the parenteral administrable tetracycline was analyzed as example for the possible applications of the tetracycline radioimmunoassay. Parallel animal tests administring 3 H tetracycline hydrochloride were performed for radioimmunoassay reference. The possible application of tetracycline radioimmunoassay in food analysis is discussed. (orig./MG) [de

  15. Analysis of changes of serum leptin, C-peptide levels and peripheral fat tissue leptin receptor expression in obesity

    International Nuclear Information System (INIS)

    Du Tongxin; Sun Junjiang; Wang Shukui; Fu Lei

    2002-01-01

    Objective: To explore the mechanism of obesity and obesity accompanied type two diabetes mellitus by investigating changes of serum leptin, C-peptide (C-P) levels and leptin receptor expression in peripheral adipose tissues. Methods: Peripheral leptin receptor density was measured via radio-ligand binding method, serum leptin and C - P levels were measured via radioimmunoassay in 91 cases (38 in obesity group, 23 in over weight, and 30 in normal controls). Results: With the increase of body mass index (BMI), the peripheral leptin receptor density of the over weight and obese cases decreased and was mash less than that of normal cases (both p<0.01, respectively). There was no statistical differences for Kd value among the three groups, suggesting no associated change between the binding ability of leptin receptor to its ligand. There was a negative correlation between BMI and leptin receptor density (r = -0.70, p < 0.01). The serum leptin and C-P levels in weight excess and obese subjects with type two DM were both increased, but significantly higher in obese group than those in weight excess group (p < 0.01). The increase of C-P was much marked than that of leptin. Serum C-P level was positively correlated with BMI. Conclusion: Changes of serum leptin, C-P levels and peripheral leptin receptor expression in cases with simple obesity and obesity accompanied with type two DM were related closely with BMI. Type 2 DM in obese subjects was related with leptin resistance and insulin resistance

  16. Radioimmunoassay of steroid hormones

    International Nuclear Information System (INIS)

    Hampl, R.; Starka, L.

    1976-01-01

    A list is given of steroids currently determined using the RIA method based on the reversible interaction of labelled and non-labelled steroids within the binding points of specific antibodies. Steroids do not have the properties of antigens, and antibodies are therefore obtained from conjugates of steroid derivatives with macromolecules where the steroid has the function of hapten. The most important synthetic methods of preparing the given derivatives are listed, and questions of the relation of the specificity of the antiserum and the structure of the respective derivative are discussed, the basic data characterizing the antiserum (titre, affinity and specificity) are described and methods are given used for measuring these variables. The technical aspects of RIA and the differences between the RIA determination of steroids and of other substances are given. The Amersham Radiochemical Centre antigens, kits and steroid hormones are recommended for use. (L.O.)

  17. Radioimmunoassay method for detection of gonorrhea antibodies

    International Nuclear Information System (INIS)

    1975-01-01

    A novel radioimmunoassay for the detection of gonorrhea antibodies in serum is described. A radionuclide is bound to gonorrhea antigens produced by a growth culture. In the presence of gonorrhea antibodies in the serum, an antigen-antibody conjugate is formed, the concentration of which can be measured with conventional radiometric methods. The radioimmunoassay is highly specific

  18. Radioimmunoassay and other related techniques

    International Nuclear Information System (INIS)

    Zarkawi, Moutaz

    1993-04-01

    The article reviews principles, requirements and reliability criteria of radioimmunoassay (RIA). Since basic reactions involved in RIA and related techniques are derived from reactions which take place in the immune system (IS) of humans and animals, the IS and the way it works will be described. In addition to RIA which involves the use of isotopes as tracers (labels), other non-radioisotopic and recent immunoassay techniques i.e. enzyme-linked immunosorbent assay (ELISA), chemiluminescence immunoassay (CLIA) and fluoroimmunoassay (FIA) will be dealt with. Some important and related terms will be defined and explained. (author). 59 refs., 4 figs

  19. Interference of immunoglobulins in two glucagon radioimmunoassays

    International Nuclear Information System (INIS)

    Von Schenck, H.; Grubb, A.O.

    1982-01-01

    Radioimmunoassays of glucagon in plasma may be complicated by interaction with other substances of high molecular mass. Precipitates of such substances with ammonium sulfate showed, after isoelectric focusing, two fractions having glucagon immunoreactivity. One fraction (pI approx.10) evidently is associated with the Fc portion (but not the Fab portion) of purified polyclonal immunoglobulin G (IgG). Equal amounts of purified monoclonal IgG of various subclasses, especially IgG 1, gave different ''glucagon'' readings, suggesting that some IgG may interfere more strongly than others. The other fraction (pI 5-6) appeared less consistently, and on gel chromatography appeared to be slightly larger than IgG. Together these fractions add about 50-100 ng/L to the immunoreactive glucagon values in plasma. Therefore methods in which glucagon is extracted before assay should be used for determining the concentration of glucagon present physiologically

  20. A sensitive radioimmunoassay of scorpion neurotoxin

    International Nuclear Information System (INIS)

    Tessier, M.; Delori, P.; Bechis, G.; Rochat, H.

    1978-01-01

    Scorpion neurotoxins form a family of homologous proteins which are basic and have approx. mol. wt. 7000. They consist of a single peptide chain crosslinked by four disulfide bridges. The complete amino acid sequences of some of them as well as the N-terminal of others, have been determined: their comparison has led to a classification into four groups. They have been shown to affect the conduction of ions through membrane channels and are thus good tools for the study of these structures on the molecular level. Toxins I and II of Androctonus australis Hector have been labelled with 125 I and specific radioactivities up to 2000 Ci/mmol have been obtained. Here the setting up of a radioimmunoassay allowing a sensitive and specific detection of toxin I of Androctonus australis Hector is reported

  1. Radioimmunoassay for progesterone in bovine milk

    International Nuclear Information System (INIS)

    Ruiz, Miriam; Figueredo, Nancy; Castillo, Sonia; Pizarro

    2002-01-01

    A system for the measurement of progesterone in bovine milk by radioimmunoassay has been developed and validated. This assay includes an iodine tracer purified by HPLC, the standard prepared in fat-free milk and an antibody anti-progesterone combined with second antibody. The detection limit of the assay is at 0.2 nmol/L calculated from the maximum binding menus two standard deviations and the precision is satisfactory. In the recovery assay was used 4 milk different samples and the result was 98% of recuperation. The progesterone was determinate in milk samples from post-partum animals taking samples three times per week for 40 days. The assay is simple, rapid and possibility the progesterone measurement without sample dilution, distinguish the cyclic changes of this hormone that reflect the ovarian activity in the animals. (author)

  2. Clinical application of radioimmunoassays

    International Nuclear Information System (INIS)

    Dolecek, R.

    1974-01-01

    The normal average values of immunoreactive insulin (IRI) in the course of the glycemic curve and in glycemia in patients suffering from diabetes, acromegaly and in diagnostics of insulinomas are given. Changes of IRI values after peroral loading with glucose in obese patients and in patients suffering from burns are given. The values of the growth hormone (STH) are given: normal, in patients suffering from obesity, children of small growth, patients with severe burns and in patients suffering from pneumoconiosis with quick progression. The conditions are also stated for the determination of the levels of the luteinizing hormone and the follicle-stimulating hormone, the human placental lactogen and values of renin activity and angiotensin in patients suffering from burns, the values of the adrenocorticotropic hormone and the thyreotropic hormone. (J.P.)

  3. Thyroid hormone radioimmunoassay

    International Nuclear Information System (INIS)

    Rodriguez, S.; Richmond, M.; Quesada, S.; Lahaman, S.; Ramirez, A.; Herrera, J.F.

    1988-01-01

    The International Atomic Energy Agency (AIEA) is carrying out the ARCAL VIII Program 'Thiroid Hormone Readioimmunoassay'. The Immunoassay Laboratory of INCIENSA is in charge of this program, with the participation of four National Hospital System laboratories, which carried out Thyroxine (T4). Triodothyroxine (T3) and Thyroid Stimulating Hormone (TSH) assays with NETRIA Reagents (North East Thames Region Immunoassay Unit). The variability was shown to be between 9-20 per cent for T4, 12-22 per cent for TSH and 22-36 per cent for T3. The study also evaluated the quality of a tracer (T3-l125 and T4 l125) produced at INCIENSA. In this case the intrassay variability was 8,4 per cent for T3 and 6,8 per cent for T4 in 32 determinations evaluated during 6 months. It was concluded that the T4 and TSH tests but not the T3 test are valid and reproducible when NETRIA Ragents are used. The tracer made at INCIENSA can be used up to 6 weeks after the radioiodination with l125. A successful thyroid-related hormones quality control was defined in Costa Rica by taking advantage of the support of a prestigious international agency, the IAEA. (author). 13 refs, 4 figs

  4. Radioimmunoassay of plasma corticotrophin

    International Nuclear Information System (INIS)

    Hummer, L.

    1977-01-01

    An assay has been established, based on antibodies against the N-terminal part of the ACTH molecule with a high affinity, a detection limit of 2 pg ACTH when assaying 200 ul unextracted plasma, and implying a total incubation time of three days. The antibody has been obtained by immunizing guinea-pigs with synthetic human 1-24 ACTH coupled to bovine serum albumin. The selected antibody has an equilibrium constant of 4 x 10 11 litres/mole in a final dilution of 1/320.000. The antiserum reacts with synthetic human 1-39 ACTH as well as with synthetic human 1-24 ACTH, and the hormonally inactive synthetic human 11-24 ACTH fragment as well as alpha- and beta-melanocyte-stimulating hormones do not cross-react in the assay. The interassay coefficient of variation of replicate estimates was 11-13%. The reproducibility of the standard curve have been evaluated by calculating the amount of ACTH corresponding to 5% of the (B/T)o value, 1.2+-0.4 pg ACTH/tube+-SD and 50% of (B/T)o value, 15.7+-2.6 pg ACTH/tube+-SD. Validation of the assay has been obtained by assaying samples from patients with verified adrenal disorders, and the accuracy is supported by ACTH determinations in test, where metyrapon had been administered intravenously. A stimulation of ACTH production by insulin-induced hypoglycaemia has been found as well. Special attention is always paid as to the conditions for the blood sampling. A reference interval of 10-76 ng/l has been found (115 normal subjects). (orig.) [de

  5. Apparatus for use in radioimmunoassays

    International Nuclear Information System (INIS)

    Chen, C-H.; Tsay, H-M.; Heyer, R.E.

    1979-01-01

    Apparatus for solid-phase antibody separation techniques used in radioimmunoassays is described in this invention. It consists of a rectangular prism tray with multiple wells protruding into its interior from one side. Near the base of the tray is an orifice used for creating evacuated condition within the structure. At the base of each well there is an orifice of such size and shape as to retain an aqueous liquid under given pressure conditions but permit the evacuation of this liquid at reduced pressure. The outlet of these orifices is in the shape of an inverted conical frustrum. Each of the wells contains an antibody coated disc of porous cellulose paper surrounded by a plastic support. The porous nature of the cellulose paper ensures contact between the antibody coating and the antigen. The use of antibody coated porous cellulose paper in combination with the vacuum operated apparatus simplifies the manipulative steps whilst still maintaining the sensitivity of the radioimmunoassay. It also obviates the need for aspiration and thus lessens the risk of contamination from one sample to another. (UK)

  6. Levels of 25(OHD3, IL-2, and C-peptide in Children with Type 1 Diabetes Mellitus (T1DM Receiving Vitamin D3 Supplementation

    Directory of Open Access Journals (Sweden)

    Tjahyo Suryanto

    2018-01-01

    Full Text Available Type 1 Diabetes Mellitus (T1DM has become a health problem in many countries. T1DM is the consequence of autoimmune destruction process of β cells. There was relationship between vitamin D deficiency with T1DM. The destruction process was caused by an imbalance of pro-inflammatory and anti-inflammatory cytokines. One of the pro-inflammatory cytokines is IL-2. C-peptide examination to see the function of beta cells due to destruction of pancreatic beta cell. Administration of vitamin D3 supplementation still cause controversy and give varying results. This randomized clinical trial was conducted to determine the levels of 25(OHD3, IL-2, and C-peptide in people with T1DM who received vitamin D3 supplementation. The subjects were 26 children with T1DM, divided into K1 group (received vitamin D3 supplementation and K2 group (received placebo. The results showed higher levels of 25(OHD3 in the K1 group and statistically found a significant difference (p = 0.00. Higher levels of IL-2 and lower C-peptide were obtained in the K1 group and no statistically significant differences were found (p = 0.76 and p= 0.26. The insignificant relationship and the negative correlation were found between 25(OHD3 and IL-2 (p = 0.71; r = - 0.12, 25(OHD3 and C-peptide (p = 0.59; r = -0.16, also levels of IL-2 and C-peptide (p = 0.13; r = -0.44 in children with type 1 diabetes who received vitamin D3 supplementation. From this study can be concluded that administration vitamin D3 supplementation in patients with T1DM can increase levels 25(OHD3 significantly. This increase has not significantly lowered levels of IL-2 and increased levels of C-peptide. However, there was an absolute decrease in the rate of slower C-peptide in the supplemented group than in the placebo group.

  7. Quantitation of avian RNA tumor virus reverse transcriptase by radioimmunoassay

    International Nuclear Information System (INIS)

    Panet, A.; Baltimore, D.; Hanafusa, T.

    1975-01-01

    A radioimmunoassay was developed that can detect and quantitate 3 ng or more of the avian RNA tumor virus reverse transcriptase. The assay detected no antigenic sites in Rous sarcoma virus α virions or in virions of a murine RNA tumor virus. About 70 molecules of reverse transcriptase were found per virion of avian myeloblastosis virus with this assay or with an assay based on antibody inhibition of enzymatic activity. The assay detected about 270 ng of enzyme per mg of cell protein in virus-producing cells; uninfected cells had much less antigenic material but contained some determinants able to displace radioactive antigen. No additional antigenic determinants on reverse transcriptase could be detected that were not found on the separated α subunit of the enzyme. Although sevenfold less sensitive than enzymatic activity as a measure of reverse transcriptase, the radioimmunoassay can detect antigen using small amounts of protein and in the presence of inhibitors

  8. Use of radioimmunoassay technique for the determination of post-partum ovaric activity in high and low milk production in dairy cows

    International Nuclear Information System (INIS)

    Villalba, P.; Paneluisa, S.; Arcos, E.

    1993-01-01

    The principal objective of this study was to determinate the post-partum ovarian activity in milking cows of high and low production in one farm of ecuadorian highland. For this experiment was necessary to use 48 animals between second and sith calving, the milk samples were collected according one pre-stablished protocol and the same was: one sample 5th or 6th days, twice a week until the cows were pregnacy and 180 days after parturitium if the cow is open. Additional data were compiled in each farm and both the results of the progesterone by RIA were used to determinate the diferents reproductive parameters in the post-partum of the cows. The most of reproductives parameters in the post-partum of the cows in the both group didn't have significance but the conception rate, services per conception, number of pregnacy cows and percentaje of non visibles heats had one high significance between the treatments

  9. Application of solid-phase radioimmunoassay in determining antibodies to Aujeszky's disease virus in blood serum of vaccinated pigs

    Energy Technology Data Exchange (ETDEWEB)

    Rodak, L.; Smid, B.; Valicek, L. (Vyzkumny Ustav Veterinarniho Lekarstvi, Brno-Medlanky (Czechoslovakia))

    1983-11-01

    In the blood sera of pigs vaccinated with inactivated vaccines manufactured by three different manufacturers the RIA method was used to determine the specific antibodies to the virus of Aujeszky's disease. In certain groups of vaccinated pigs the results of the RIA examination are unfavourably affected by the bond of antibodies to the cellular antigenous determinants. This proves that following vaccination antibodies are formed not only against the viral antigen but also against the antigens of cells on which the vaccination virus is propagated. These shortcomings are eliminated by the use of suitable cellular cultures for the preparation of viral and control antigens. Antigens are applicable for RIA and for ELISA examinations of blood sera of infected and vaccinated pigs. The advantages are described of the RIA and ELISA methods as compared with the virus neutralization test.

  10. Radioimmunoassay for nortriptyline and amitriptyline

    International Nuclear Information System (INIS)

    Turner, P.

    1977-01-01

    A description has been given (Aherne, G.W.; Marks, V.; Mould, G.; Stout, G.; Lancet; 1214, June 4 (1977)) of a radioimmunoassay (RIA) technique having advantages for monitoring patient response by estimation of plasma concentrations of nortriptyline and amitriptyline. A wide range of monoamine-reuptake-inhibiting drugs is now used in the treatment of depressive illness. There are other analytical techniques such as gas-liquid chromatography which can be used in the estimation of most of these drugs and their major metabolites, as well as for the identification of some other centrally-acting drugs such as benzodiazepines. The chromatographic technique was able to detect the administration of the wrong drug in one comparative study of two antidepressive drugs. Chromatographic and RIA methods therefore both have their own analytical roles according to the clinical or research problem being investigated. (U.K.)

  11. The radioimmunoassay of steroid glucuronides

    International Nuclear Information System (INIS)

    Chaudhri, B.

    1980-07-01

    A radioimmunoassay method for steroid glucuronides in which the second carboxylated group has been introduced into the steroid structure and used to attach the hapten to the protein. The unequivocal attachment through the second group, rather than through the glucuronide is achieved by leaving the glucuronide protected as its triacetyl methyl-ester (g.a.m.e.) until after the hapten has been coupled to the protein. The hapten, immunogens and antisera to costrone-3-glucuronide have been prepared using a 17-carboxymethyloxime bridge. The antisera raised to these immunogens have been characterised for their ability to discriminate between the free steroid and the steroid glucuronide, and evaluated for use in immunoassay. (author)

  12. Radioimmunoassay for chlorpromazine in plasma

    International Nuclear Information System (INIS)

    Midha, K.K.; Loo, J.C.K.; Hubbard, J.W.; Rowe, M.L.; McGilveray, I.J.

    1979-01-01

    A radioimmunoassay for chlorpromazine in plasma is described. The antiserum was obtained by immunizing rabbits with a conjugate of bovine serum albumin and N-(2-carboxyethyl)desmethylchlorpromazine. It is specific for chlorpromazine and its minor active metabolite, N-desmethylchlorpromazine. Other known active or inactive chlorpromazine metabolites and other psychotropic drugs tested do not cross react with the antiserum. Less than 34 pg of the drug can be detected in 200 μL of plasma. As many as 100 samples can be processed in a day by one technician. Concentrations of chlorpromazine can be measured in 200-μL samples of plasma collected as late as 48 h after a single oral 25-mg dose

  13. Methadone radioimmunoassay: two simple methods

    International Nuclear Information System (INIS)

    Robinson, K.; Smith, R.N.

    1983-01-01

    Two simple and economical radioimmunoassays for methadone in blood or urine are described. Haemolysis, decomposition, common anticoagulants and sodium fluoride do not affect the results. One assay used commercially-available [1- 3 H](-)-methadone hydrobromide as the label, while the other uses a radioiodinated conjugate of 4-dimethylamino-2,2-diphenylpentanoic acid and L-tyrosine methyl ester. A commercially-available antiserum is used in both assays. Normethadone and α-methadol cross-react to a small extent with the antiserum while methadone metabolites, dextropropoxyphene, dipipanone and phenadoxone have negligible cross-reactivities. The 'cut-offs' of the two assays as described are 30 and 33 ng ml -1 for blood, and 24 and 21 ng ml -1 for urine. The assay using the radioiodinated conjugate can be made more sensitive if required by increasing the specific activity of the label. (author)

  14. Development of antiserum against bovine prolactin for radioimmunoassay

    International Nuclear Information System (INIS)

    Razdan, M.N.; Kaker, M.L.; Galhotra, M.M.

    1980-01-01

    Antiserum against bovine prolactin was raised in male rabbits and tested against crossreacting contaminants by immunodiffusion and immunoelectrophoresis. One sharp precipitin band against prolactin was observed. The antiserum showed a small faint band against bovine growth hormone. No crossreaction was observed against bovine follicle stimulating hormone, bovine luteinizing hormone, bovine thyroid stimulating hormone and normal calf serum. The crossreaction with bovine growth hormone vanished after treating the antiserum with normal calf serum. Antibody titre of the absorbed anti-prolactin serum determined by radioimmunoassay was high, which could bind 31.30% at 1:10,000 final dilution. Maximum binding was not inhibited by the addition of higher amounts of contaminants, suggesting that the absorbed antiserum was immunologically monospecific and could be used for radioimmunoassay work. (author)

  15. Radioimmunoassay of steroids in Czechoslovakia - current state and prospects

    International Nuclear Information System (INIS)

    Hampl, R.; Starka, L.; Putz, Z.; Dvorak, P.

    1984-01-01

    The experience is summarized with radioimmunoassay of steroids during the last 15 years, and the expected trends in this field are dealt with. The following problems connected with the radioimmunoassay of steroids are discussed: 1) ways leading to improved antisera specificity (choice of immunogen, use of the principle of immunological tolerance, use of antisera mixtures, preparation of monoclonal antibodies); 2) methods of ligand labelling (steroids labelled in the ring, radioiodine labelled derivative); 3) separation techniques of bound and free ligands; 4) sample preparation with regard to automation and 5) importance of and approaches to the determination of free, plasma protein non-bound steroids. The survey is complemented with a list of antisera to steroids, prepared in the laboratories of the authors. (author)

  16. The subcellular and organ distribution and natural form of histidyl-proline diketopiperazine in rat brain determined by a specific radioimmunoassay.

    Science.gov (United States)

    Yanagisawa, T; Prasad, C; Peterkofsky, A

    1980-11-10

    Histidyl-proline diketopiperazine is produced in brain as a product of the metabolism of thyrotropin-releasing hormone. A number of the previously observed central nervous system and pituitary activities resulting from an exposure to thyrotropin-releasing hormone appear to involve the conversion of the releasing factor to the cyclic dipeptide. In the present study, the development of a rabbit antiserum that is highly specific for histidyl-proline diketopiperazine is described; the antiserum has essentially no capability to bind thyrotropin-releasing hormone or a number of other related peptides. The antibody can also distinguish between the natural form of the cyclic dipeptide and a diastereomer containing D-proline. A procedure for extraction, with high yield, of histidyl-proline diketopiperazine from brain is described. With the aid of the specific antiserum it was found that the preponderance of the cyclic dipeptide in rat brain is bound to high molecular weight material, mainly in the range of Mr = 70,000; histidyl-proline diketopiperazine can be disassociated from this material by boiling in salt/methanol solution. The concentration of the dipeptide in rat brain is in the range of 275 to 565 pmol/brain, approximately 2.5 times the concentrations determined for thyrotropin-releasing hormone (113 to 210 pmol/brain). A study of the subcellular distribution of histidyl-proline diketopiperazine and thyrotropin-releasing hormone suggests that the releasing factor is concentrated in synaptosomal vesicles while the diketopiperazine is not. A determination of the regional distribution of thyrotropin-releasing hormone and histidyl-proline diketopiperazine indicated that both peptides are found in highest concentrations in pituitary and hypothalamus, but are detectable in other areas of brain as well.

  17. A newly developed precise and sensitive radioimmunoassay for clonidine

    International Nuclear Information System (INIS)

    Arndts, D.; Struck, C.J.; Staehle, H.

    1979-01-01

    A new precise and sensitive radioimmunoassay for clonidine has been developed. Synthesis and analysis of the hapten (4-carboxy-clonidine; St 1984) as well as antibody production in rabbits are described in detail. At a final dilution of 1:1000 the resulting immune serum binds 50% of a tritiated clonidine standard containing 1 ng of clonidine. The detection limit of the presented radioimmunoassay for clonidine is 0.1 ng/ml. The coefficient of variation did not exceed 4.3% for any of 7 standard determinations with 5 replicates. There was no relevant crossreactivity of inactive clonidine metabolites apart from 4-OH-clonidine. To avoid any errors from cross-reaction clonidine was selectively and quantitatively extracted into diethylether from unknown plasma samples. Following concentration of the extracts even such low concentrations as 20 pg of clonidine/ml plasma were detectable. With the radioimmunoassay applied in pharmacokinetic studies a maximal clonidine concentration in blood plams of healthy human volunteers was determined to 0.6 ng/ml 1.5 h after oral administration of 150 μg. (orig.) [de

  18. Investigations of serum HPL during pregnancy using two different radioimmunoassays

    International Nuclear Information System (INIS)

    Stracke, H.

    1978-01-01

    The interassay investigations showed that it is absolutely necessary to standardize the HPL antisera as well as the standard sera, as it is otherwise impossible to compare and interpret the findings of different HPL radioimmunoassays. The investigations have shown that in addition to conventional clinical examinations and laboratory test methods (urine estriol determination, DHEAS-dehydroepiandrosterone sulphate test-, urine pregnandiol determination, and determination of heat-resisting alkaline serum phosphatase), HPL concentration determination is a parameter of the nutritive function of the placenta. (orig.) [de

  19. Relation of muscle indices with metabolic parameters and C-peptide in type 2 diabetes mellitus

    International Nuclear Information System (INIS)

    Tuzun, S.; Oner, C.; Dabak, M.R.; Kasikci, H.O.; Sargin, M.

    2017-01-01

    Objective: To assess the relation between bioimpedance measurements and metabolic parameters and C-peptide in patient with type 2 diabetes mellitus (DM). Study Design: Cross-sectional study. Place and Duration of Study: Kartal Dr Lutfi Kirdar Training and Research Hospital, Pendik Kaynarca Diabetes Center, Exercise and Metabolism Unit, between January and March 2015. Methodology: Patients with DM, aged less than 65 years, were assessed for bioimpedance analysis, fasting plasma glucose (FPG), HbA1c, C-peptide levels, triglyceride levels, LDL-cholesterol, and HDL-cholesterol levels. Skeletal muscle index, total muscle index, skeletal muscle percentage, and total muscle percentage were used for muscle-related analyses. Mann-Whitney U-test or independent t-test were used to compare differences between two independent groups. Pearson correlation test or Spearman correlation test were used to find out correlation between variables. Results: A total of 359 DM patients were enrolled in the study. Mean age was 51.6+-8.0 years, and 278 (77.7%) of the participants were females. After adjusting age and gender variables, there was no relation between muscle-related measurements and FPG, triglyceride, LDL-cholesterol (p>0.05). However, there was muscle-related indexes (MRI) positively correlation with C-peptide and inversely associated with HDL-cholesterol (p<0.05). Conclusion: Muscle-related indices positively correlated with C-peptide, which showed endogenous insulin reserve. (author)

  20. Automation of steroid radioimmunoassays for clinical and research purposes

    International Nuclear Information System (INIS)

    Vihko, R.; Hammond, G.L.

    1979-01-01

    In recent years an exponential increase in the research and clinical application of radioimmunoassays has created a demand for manipulative aids, to increase the general efficiency of the technique as well as precision of the determinations. At present a number of systems exist for sample preparation and the automation of assays. However, due to inherent problems of carry-over, priming, cleaning and the necessity for chemically inert components most of these systems tend to be rather inflexible. The instrument of choice ought therefore to be extremely versatile and provide the operator with a wide spectrum of alternatives, in order to optimize the initial capital outlay. Moreover, in the light of technological developments in the field of simultaneous, multisample gamma-counting and data processing, it is anticipated that a new generation of multisample processors will emerge of sufficient flexibility to accommodate the wide variety of assay protocols in present use. In this paper the problems encountered in the development of automated techniques for the radioimmunoassay of steroid hormones are reviewed, and a preliminary description of a versatile modular discrete instrument for the automation of radioimmunoassays is presented, which is based on simultaneous multisample preparation, and subsequent counting and data processing. (author)

  1. Oxytocin determination by radioimmunoassay in cattle. 2

    International Nuclear Information System (INIS)

    Schams, D.; Baumann, G.; Leidl, W.

    1982-01-01

    Oxytocin concentration in jugular vein blood was measured radioimmunologically with a detection limit of 3 pg/ml plasma in male and female cattle. Five bulls were tested; during mating a cow in oestrus with intromission and ejaculation, during mounting a dummy or another bull with ejaculation into an artificial vagina or during false mounts. No increase in oxytocin concentrations could be observed, but stimulation with an electro-ejaculator caused an increase ranging from 5-84 pg/ml after a latent period of 3-5 min. A similar response was observed in two cows following the same procedure. The contact with a bull, false mount or mating with intromission and ejaculation was not followed by a measurable oxytocin release in 5 test cows. The following stimulation techniques, massage of vulva and clitoris, massage of cervix and uterus per rectum, artificial insemination, introduction of a speculum into the vagina or insufflation of air into the vagina were performed with 5 cows and 5 heifers. Insufflation of air into the vagina was the most effective stimulus, eleciting an oxytocin release up to 588 pg/ml. All 5 heiers responded positively, as well as 4 cows in oestrus. The other manipulations cuased an oxytocin response mainly in heifers (whether in oestrus or dioestrus), whereas only one cow in oestrus responded with an oxytocin release. In general, oxytocin concentrations increase about 30-90 s after the start of the stimulus. (author)

  2. The radioimmunoassay of steroid glucuronides

    International Nuclear Information System (INIS)

    Chaudhri, R.

    1980-07-01

    A modified radioimmunoassay for steroid glucuronides is described. A second carboxylated group is introduced into the steroid structure and used to attach the hapten to the protein. The unequivocal attachment through the second group, rather than through the glucuronide is achieved by leaving the glucuronide protected as its triacetyl methylester until after the hapten has been coupled to the protein. Subsequently, the glucuronide can be exposed by mild alkaline hydrolysis or alternatively, the protected immunogen can be injected into the rabbits, leaving the animals to deprotect the hapten. The hapten, immunogens and antisera to oestrone-3-glucuronide have been prepared using a 17-carboxymethyloxime bridge. The hapten, immunogen and antisera to pregnanediol-3 α - glucuronide have also been prepared using a 6 β - hemisuccinoxy bridge. A study has been made of the reactive properties of the 6 β-hydroxyl group and its effect on the stereo-specificity of reduction of 4-ene and the 3-oxo group and on the reactivity of the 3 α-hydroxyl group. The antisera raised to these immunogens have been characterised for their ability to discriminate between the free steroid and the steroid glucuronide, and evaluated for use in immunoassay. (author)

  3. Radioimmunoassay of canine growth hormone

    International Nuclear Information System (INIS)

    Eigenmann, J.E.; Eigenmann, R.Y.

    1981-01-01

    A sensitive radioimmunoassay (RIA) for canine growth hormone (GH) was developed. Antibodies were elicited in rhesus monkeys. One antiserum exhibited a working titer at a dilution of 1:500 000. Radioiodination was performed enzymatically employing lactoperoxidase. Logit-log transformation and least squares fitting resulted in straight line fitting of the standard curve between 0.39 and 50 ng/ml. Formation of large-molecular [ 125 I]GH during storage caused diminished assay sensitivity. Therefore [ 125 I]GH was re-purified by gel chromatography. Using this procedure, high and reproducible assay sensitivity was obtained. Tracer preparations were used for as long as 3 months after iodination. Diluted plasma from normal and acromegalic dogs resulted in a dose-response curve parallel to the standard curve. Canine prolactin exhibited a cross-reactivity of 2%. The within-assay coefficient of variation (CV) was 3.8 and the between-assay CV was 7.2%. Mean plasma GH concentration in normal dogs was 1.92 +- 0.14 ng/ml (mean +- SEM.) GH levels in acromegalic dogs were appreciably higher. Insulin-induced hypoglycaemia, arginine and ornithine administration resulted in inconsistent and sluggish GH increment. A better response was obtained by injecting a low dose of clonidine. Clonidine administration to hypopituitary dogs resulted in absent or poor GH increment. (author)

  4. The Role of C-Peptide as Marker of Cardiometabolic Risk in Women With Polycystic Ovary Syndrome: A Controlled Study.

    Science.gov (United States)

    de Medeiros, Sebastiao Freitas; Angelo, Laura Camila Antunes; de Medeiros, Matheus Antonio Souto; Banhara, Camila Regis; Barbosa, Bruna Barcelo; Yamamoto, Marcia Marly Winck

    2018-03-01

    The aim of this study was to examine the role of C-peptide as a biological marker of cardiometabolic risk in polycystic ovary syndrome (PCOS). This case-control study enrolled 385 PCOS patients and 240 normal cycling women. Anthropometric and clinical variables were taken at first visit. Fasting C-peptide, glucose, lipids, and hormone measurements were performed. Simple and multiple correlations between C-peptide and other variables associated with dysmetabolism and cardiovascular disease were examined. C-peptide was well correlated with several anthropometric, metabolic, and endocrine parameters. In PCOS patients, stepwise multiple regression including C-peptide as the criterion variable and other predictors of cardiovascular disease risk provided a significant model in which the fasting C-peptide/glucose ratio, glucose, body weight, and free estrogen index (FEI) were retained (adjusted R 2 = 0.988, F = 7.161, P = 0.008). C-peptide levels alone or combined with C-peptide/glucose ratio, glucose, body weight, and FEI provided a significant model to identify PCOS patients with higher risk of future cardiometabolic diseases.

  5. Radioimmunoassay of penicilloyl groups in biological fluids

    International Nuclear Information System (INIS)

    Wal, J-M.; Bories, G.

    1975-01-01

    Penicilloyl-protein conjugates may be formed in man or animals after therapeutic treatment but cannot be detected by the classical microbiological assay methods used for penicillin. Allergies have been noted in consumers of products coming from animals treated with penicillin (milk particularly). Although these compounds present a risk to public health, they passed unnoticed through hygienic food inspection. Therefore a specific and sensitive method was devised for the assay of these derivatives in biological fluids where they can be present in trace amounts. An iodine-125 labelled conjugate has been prepared. Already usable for the detection of antipenicilloyl antibodies in sera of penicillin allergic patients, it has been used for the development of a radioimmunoassay of penicilloyl groups. Assay is done directly on milk, urine and serum without previous extraction and with a detection limit of a few ppb. It permits a rapid, specific and easy to handle determination in the sera of hospital patients as well as in the inspection of animal products at the slaughter house and at the dairy

  6. Elevated C-peptide and insulin predict increased risk of colorectal adenomas in normal mucosa

    International Nuclear Information System (INIS)

    Vidal, Adriana C; Keku, Temitope O; Lund, Pauline Kay; Hoyo, Cathrine; Galanko, Joseph; Burcal, Lauren; Holston, Rachel; Massa, Berri; Omofoye, Oluwaseun; Sandler, Robert S

    2012-01-01

    Lower concentrations of the insulin–like growth factor binding protein-1 (IGFBP-1) and elevated concentrations of insulin or C-peptide have been associated with an increase in colorectal cancer risk (CRC). However few studies have evaluated IGFBP-1 and C-peptide in relation to adenomatous polyps, the only known precursor for CRC. Between November 2001 and December 2002, we examined associations between circulating concentrations of insulin, C-peptide, IGFBP-1 and apoptosis among 190 individuals with one or more adenomatous polyps and 488 with no adenomatous polyps using logistic regression models. Individuals with the highest concentrations of C-peptide were more likely to have adenomas (OR = 2.2, 95% CI 1.4-4.0) than those with the lowest concentrations; associations that appeared to be stronger in men (OR = 4.4, 95% CI 1.7-10.9) than women. Individuals with high insulin concentrations also had a higher risk of adenomas (OR = 3.5, 95% CI 1.7-7.4), whereas higher levels of IGFBP-1 were associated with a reduced risk of adenomas in men only (OR = 0.3, 95% CI 0.1-0.7). Overweight and obese individuals with higher C-peptide levels (>1 st Q) were at increased risk for lower apoptosis index (OR = 2.5, 95% CI 0.9-7.1), an association that remained strong in overweight and obese men (OR = 6.3, 95% CI 1.0-36.7). Higher levels of IGFBP-1 in overweight and obese individuals were associated with a reduced risk of low apoptosis (OR = 0.3, 95% CI 0.1-1.0). Associations between these peptides and the apoptosis index in overweight and obese individuals, suggest that the mechanism by which C-peptide could induce adenomas may include its anti-apoptotic properties. This study suggests that hyperinsulinemia and IGF hormones predict adenoma risk, and that outcomes associated with colorectal carcinogenesis maybe modified by gender

  7. Evaluation of a radioimmunoassay for the determination of anti-native DNA antibodies. Evaluation d'une technique radio-immunologique pour la detection des anticorps anti-ADN natif

    Energy Technology Data Exchange (ETDEWEB)

    Johanet, C.; Soulie, E.; Absalon, Y.B.; Ocwieja, T.; Abuaf, N. (Hopital Saint-Antoine, 75 - Paris (FR))

    1991-01-01

    The anti-native DNA antibodies were measured by a radioimmunoassay (RIA) type Farr assay in the sera from 648 patients: 108 with active or inactive systemic lupus erythematosus (SLE), 181 with clinical symptoms of another connective tissue disease, 171 with liver diseases, 29 with different pathology and 159 normal sera were obtained from a blood bank. The anti-DNA kit has been calibrated against the first international units/ml. This assay has proved to be sensitive and specific, and appears to be reliable for the diagnosis and follow-up of SLE patients. The authors propose a new reference cut-off level higher than producer's one.

  8. Preparation, calibration and evaluation of the First International Standard for human C-peptide.

    Science.gov (United States)

    Moore, Melanie; Dougall, Thomas; Ferguson, Jackie; Rigsby, Peter; Burns, Chris

    2017-07-26

    Measurement of C-peptide by immunoassay contributes to the diagnosis of a number of disorders related to β cell function. Stocks of the current international reference reagent (IRR) for C-peptide, used to calibrate these immunoassays, are exhausted, and this report summarises the international study to establish a replacement World Health Organization (WHO) international standard (IS) to maintain the availability of a globally available reference material and support efforts to standardise C-peptide assays. The study was conducted in three phases; phase I involved the assignment of a value to a primary calibrant in mass units by amino acid analysis and phase II applied this value to the calibration of a candidate standard, 13/146, by reversed phase high-performance liquid chromatography (RP-HPLC) assay. In phase III, the candidate standard was compared to the first IRR by current immunoassays to assess its suitability to serve as an IS. Calibration of the candidate standard by RP-HPLC gave a final estimated content of 8.64 μg/ampoule with expanded uncertainty of 8.21-9.07 μg/ampoule (95% confidence; k=2.45). The candidate standard also appears sufficiently stable to serve as an IS, based on HPLC analysis of accelerated thermal degradation samples of 13/146, and was also shown to have appropriate immunological activity. A difference in bias approach was used to assess the commutability of 13/146 with human serum and urine samples. With the exception of two laboratories, the candidate standard demonstrated commutability with respect to the serum and urine samples included in this study. The candidate standard, 13/146, is suitable to serve as the First International Standard for human C-peptide, and it has been formally adopted by the Expert Committee on Biological Standardisation of the WHO.

  9. Basal C-peptide Level as a Surrogate Marker of Subclinical Atherosclerosis in Type 2 Diabetic Patients

    Directory of Open Access Journals (Sweden)

    Sung-Tae Kim

    2011-02-01

    Full Text Available BackgroundRecent studies have revealed that C-peptide induces smooth muscle cell proliferation and causes human atherosclerotic lesions in diabetic patients. The present study was designed to examine whether the basal C-peptide levels correlate with cardiovascular risk in type 2 diabetes mellitus (T2DM patients.MethodsData was obtained from 467 patients with T2DM from two institutions who were followed for four years. The medical findings of all patients were reviewed, and patients with creatinine >1.4 mg/dL, any inflammation or infection, hepatitis, or type 1 DM were excluded. The relationships between basal C-peptide and other clinical values were statistically analyzed.ResultsA simple correlation was found between basal C-peptide and components of metabolic syndrome (MS. Statistically basal C-peptide levels were significantly higher than the three different MS criteria used in the present study, the Adult Treatment Panel III (ATP III of the National Cholesterol Education Program's (NCEP's, World Health Organization (WHO, and the International Diabetes Federation (IDF criteria (NCEP-ATP III, P=0.001; IDF, P<0.001; WHO, P=0.029. The multiple regression analysis between intima-media thickness (IMT and clinical values showed that basal C-peptide significantly correlated with IMT (P=0.043, while the analysis between the 10-year coronary heart disease risk by the United Kingdom Prospective Diabetes Study risk engine and clinical values showed that basal C-peptide did not correlate with IMT (P=0.226.ConclusionBasal C-peptide is related to cardiovascular predictors (IMT of T2DM, suggesting that basal C-peptide does provide a further indication of cardiovascular disease.

  10. Radioimmunoassay of thyrotropin concentrated from serum

    International Nuclear Information System (INIS)

    Nisula, B.C.; Louvet, J.P.

    1978-01-01

    A method for concentrating human TSH (hTSH) from serum for use in RIAs is described. The method takes advantage of the affinity of the plant lectin, concanavalin A, for the carbohydrate portion of the hTSH molecule. The hTSH from 2.5 ml serum was adsorbed to concanavalin A covalently linked to sepharose and then radioimmunoassayed using the hTSH antiserum and hTSH for iodination distributed by the National Pituitary Agency. For the RIA standard curve, the hTSH reference preparation was concentrated from a serum wwith undetectable hTSH in order to correct for recovery and to control for nonspecific effects. The percentage of serum hTSH extracted from 2.5 ml serum with the concentration procedure was 76.6 +- 3.4% (mean +- SD). The coefficient of correlation between serum hTSH, determined with the concentration procedure, and serum hTSH determined without was 0.979 (P < 0.001). Over 95% of normal adult men and women had detectable levels of serum hTSH, ranging from < 0.56 to 4.0 μU/ml. The mean of detectable serum hTSH levels in normal adult women (n = 11) was 1.54 +- 1.03 μU/ml (mean +- SD) and in normal men (n = 9) was 2.02 +- 1.15 μU/ml (mean +- SD). Clinically hyperthyroid patients with diffuse and nodular toxic goiters (n = 8) and patients with hypothyroidism secondary to pituitary disease (n = 6), four of whom were taking replacement doses of thyroid hormone, had undetectable serum hTSH levels. Serum hTSH in patients with primary hypothyroidism uniformly exceeded the normal range. This hTSH concentrating procedure enhances the effective sensitivity and, therefore, the clinical utility of the RIA for hTSH in serum

  11. Prediction of ovulation in women using a rapid progesterone radioimmunoassay

    Energy Technology Data Exchange (ETDEWEB)

    Fleming, R.; Coults, J.R.T. (Glasgow Univ. (UK))

    1982-02-01

    A rapid (3-h) radioimmunoassay of plasma progesterone has been developed and used successfully to predict the time of ovulation in women undergoing artificial insemination. The results obtained using progesterone levels to date the stage of the cycle were analysed retrospectively by (1) estimation of the length of the ensuing luteal phases and comparison of these with luteal phase lengths of a control group (2) comparison of the dating using progesterone levels with retrospective determination of LH values and (3) by analysis of the dating in cycles in which conception occurred.

  12. Quality control in radioimmunoassay for Argentina, Chile, Paraguay and Uruguay

    International Nuclear Information System (INIS)

    Quiroga, S.

    1984-10-01

    The purpose of this project was the development of an External Quality Control Programme on Radioimmunoassay among laboratories from Argentina and other Latinoamerican countries. The purpose of this programme was to improve the performance of the participating laboratories in order to increase the diagnostic value of patient results. The number of returns of this programme (Buenos Aires I) were compared against those of the previous one (Programme I) (Contract 2737/RB) to determine if the objectives were fulfilled. The preparation of the samples and the evaluation of the results of the first six samples were analyzed in the progress report sent on December 30th, 1983 and were reanalysed including late results

  13. Measurement of alpha-fetoprotein in maternal serum: three commercial radioimmunoassay kits and two non-commercial radioimmunoassays compared

    International Nuclear Information System (INIS)

    Forest, J.C.; Verreault, F.; Pouliot, M.

    1982-01-01

    We evaluated three commercial radioimmunoassay kits (Amersham, Dainabot, Clinical Assays) and two non-commercial methods for determining alpha-fetoprotein in maternal serum during pregnancy. All five procedures were found to be acceptable with respect to practicability, sensitivity, linearity, and precision. Similar results were obtained with Dainabot, Clinical Assays, and the two non-commercial methods, but the Amersham method revealed a proportional error, results being about 20% lower than those by the other methods. Use of the international unit system is suggested for reporting results for AFP, to facilitate comparison between methods and laboratories

  14. The Effects of C-peptide on Type 1 Diabetic Polyneuropathies and Encephalopathy in the BB/Wor-rat

    Directory of Open Access Journals (Sweden)

    Anders A. F. Sima

    2008-01-01

    Here the effects of C-peptide replenishment will be extensively described as they pertain to DPN and diabetic encephalopathy, underpinning its beneficial effects on neurological complications in type 1 diabetes.

  15. Study on the relationship between fasting blood sugar and GH, C-peptide levels in patients with DM2

    International Nuclear Information System (INIS)

    Cai Facheng; Chen Lishu; Hong Kai; Lin Meishan

    2006-01-01

    Objective: To investigate the relationship between fasting blood sugar (FBG) and growth hormone (GH), C-peptide (CP) levels in patients with type II diabetes mellitus (DM2). Methods: Serum fasting glucose (with biochemical method) GH, C-peptide (with RIA) levels were measured in 64 patients with DM2 and 31 controls. Results: In the 64 patients, 40 were relatively well-controlled (FBG <9.0mmol/L) and 24 were relatively poorly-controlled (FBG ≥ 9.0mmol/L), The serum GH levels in the poorly controlled group were significantly higher than those in the well-controlled group (P<0.01), which, in turn, were significantly higher than those in the controls (P<0.01). The reverse was exactly true for the C-peptide levels. Conclusion: The higher GH and lower C-peptide levels might be a contributory, cause of the inadequate control in these patients. (authors)

  16. Effect of gestational age and blood glucose on C-peptide excretion rate and clearance in neonates.

    Science.gov (United States)

    Salis, Emma R; Soelbeck, Mikkel K; Reith, David M; Wheeler, Benjamin J; Broadbent, Roland S; Medlicott, Natalie J

    2016-01-01

    The aim of this study was to measure urinary C-peptide concentrations, and then calculate C-peptide clearance (Cl), and excretion rate (UER) in neonates. In addition, the effect of gestational age (GA) and blood glucose levels (BGL) on C-peptide UER were investigated. Insulin concentrations in plasma and C-peptide concentrations were measured in plasma and urine, in 20 neonates. Chemiluminescent immunoassays were used for insulin and C-peptide measurements, with urine diluted to 40% with bovine serum albumin 1% in phosphate buffered saline. Urine volume and time of collection were recorded and used to calculate UER and Cl. The mean Cl of C-peptide was 0.309 ± 0.329 mL/min/kg, and UER was 0.0329 ± 0.0342 pmol/min/kg. Correlations between Cl or UER and GA were not significant (P > 0.05). No significant correlation was shown between Cl or UER and BGL (P > 0.05). Both Cl and UER were highly variable in neonates, but were not correlated with GA. Additionally, BGL did not appear to affect C-peptide UER and Cl. As GA and BGL did not appear to affect Cl and UER, urinary C-peptide may provide a non-invasive method of measuring insulin production in neonates. © 2015 The Authors. Journal of Paediatrics and Child Health © 2015 Paediatrics and Child Health Division (Royal Australasian College of Physicians).

  17. Role of C-peptide in Altered Lipid Profile among Apparently Healthy Adults of Vijayapura City, Karnataka

    Directory of Open Access Journals (Sweden)

    Chandrahas M.Kulkarni

    2016-04-01

    Full Text Available Background: C-peptide is produced in equimolar concentration during insulin production as inactive molecule by beta islet cells of Langerhans. C-peptide is most useful biomarker of endogenous insulin production. Aim and Objectives: To predict metabolic syndrome in advance by estimation of C-peptide and lipid profile in healthy adults. Material and Methods: Serum C-peptide, fasting blood glucose and lipid profile of 128 healthy individuals were estimated. Adults in the age group of 18 to 60 years of both sexes were included in study. Results: C-peptide levels were increased in 27%, Serum cholesterol in 30%, LDL Cholesterol in 55% and triglyceride levels in 21% of healthy individuals. Significant correlation was observed between C peptide, age, serum cholesterol, LDL and cholesterol LDL ratio in male subjects only. In our study group most of the subjects (both males and females fell in overweight group. Conclusion: Cpeptide level and lipid profile may be considered as useful biomarkers to predict type 2 diabetes mellitus in advance, possibly due to insulin resistance.

  18. The Association Between Fasting C-peptide and Gastrointestinal Symptoms of Gastroparesis in Type 2 Diabetic Patients.

    Science.gov (United States)

    Huang, Yun; Zhang, Honghong; Zhang, Minxia; Li, Wenya; Wang, Jinhua; Hu, Ji

    2017-04-30

    The relationship between C-peptide levels and gastrointestinal (GI) symptoms in type 2 diabetic patients is not clear. The purpose of this study is to examine the association between fasting C-peptide and GI symptoms of gastroparesis in type 2 diabetic patients. We recruited 333 type 2 diabetic patients into the present study. All patients filled out questionnaires of gastroparesis cardinal symptom index (GCSI) to evaluate GI symptoms. Hospital anxiety and depression scale were adopted to define anxiety and depression. Patients with GCSI scores ≥ 1.9 were regarded as having symptoms of gastroparesis. In our study, 71 (21.3%) type 2 diabetic patients had GCSI scores ≥ 1.9. In comparison to patients with scores fasting c-peptide levels (1.49 ng/mL vs 1.94 ng/mL, P fasting C-peptide was still significantly associated with symptoms of gastroparesis (odds ratio, 0.67; 95% confidence intervals, 0.48-0.94; P = 0.021), even after adjustments for age, sex, body mass index, HbA1c, current smoking and drinking status, anxiety, and depression. Furthermore, linear regressions showed that fasting C-peptide was independently and negatively related to GCSI scores (standardized regression coefficient, -0.29; P fasting C-peptide levels independent of depression and anxiety status.

  19. Evaluation of sequence variability in HIV-1 gp41 C-peptide helix-grafted proteins.

    Science.gov (United States)

    Tennyson, Rachel L; Walker, Susanne N; Ikeda, Terumasa; Harris, Reuben S; McNaughton, Brian R

    2017-08-01

    Many therapeutically-relevant protein-protein interactions (PPIs) have been reported that feature a helix and helix-binding cleft at the interface. Given this, different approaches to disrupting such PPIs have been developed. While short peptides (<15 amino acids) typically do not fold into a stable helix, researchers have reported chemical approaches to constraining helix structure. However, these approaches rely on laborious, and often expensive, chemical synthesis and purification. Our premise is that protein-based solutions that stabilize a therapeutically-relevant helix offer a number of advantages. In contrast to chemically constrained helical peptides, or minimal/miniature proteins, which must be synthesized (at great expense and labor), a protein can be expressed in a cellular system (like all current protein therapeutics). If selected properly, the protein scaffold can stabilize the therapeutically-relevant helix. We recently reported a protein engineering strategy, which we call "helix-grafted display", and applied it to the challenge of suppressing HIV entry. We have reported helix-grafted display proteins that inhibit formation of an intramolecular PPI involving HIV gp41 C-peptide helix, and HIV gp41 N-peptide trimer, which contain C-peptide helix-binding clefts. Here, we used yeast display to screen a library of grafted C-peptide helices for N-peptide trimer recognition. Using 'hits' from yeast display library screening, we evaluated the effect helix mutations have on structure, expression, stability, function (target recognition), and suppression of HIV entry. Copyright © 2017. Published by Elsevier Ltd.

  20. Purification of subunits from human chorionic gonadotropin and radioimmunoassay

    International Nuclear Information System (INIS)

    Okumura, Hajime; Sudo, Tadamitsu; Fujisawa, Munetoshi; Namba, Shuichi; Matsushima, Sanae

    1976-01-01

    A crude hCG with an activity of about 3,000 IU per mg was purified to 10,000-15,000 IU per mg of dry weight using Amberlite CG-50 chromatography combined with DEAE-Sephadex A-50 and Sephadex G-75. The alpha and beta subunits of hCG were prepared by urea-treatment of the hormone and were isolated by DEAE-Sephadex A-50 chromatography. Further purification of the subunits was achieved by gel filtration on a Sephadex G-57 column. For radioimmunoassay, hCG was iodinated by the DMSO-chloramine T method. Iodination of hCG with non-radioactive iodine revealed that the addition of DMSO to the iodination mixture seemed to reduce the iodination damage to the antigenic activity of the hormone. The hCG iodinated with non-radioactive iodine (accomplished by the DMSO-chloramine T method) was 1.5 times more immunoreactive in the hCG radioimmunoassay then the hCG iodinated by the usual chloramine T method. The radioimmunoassay of the hCG-beta subunit developed in our laboratory was satisfactory with respect to specificity. The hLH, hFSH, hTSH and hCG-alpha subunits tested cross-reacted very poorly in our assay system. Desialylated-hCG and subunits, in which the biologic potency was almost zero, also exhibited decreased immunoreactivity, about 30% of the native hormone with grossly unimpaired parallelism in their respective homologous radioimmunoassays. The concentrations of hCG and the subunits were determined on human sera from pregnant patients. The hCG levels reached to a peak at the first trimester of the pregnancy, but the hCG-beta subunits varied poorly in their concentrations throughout the periods of pregnancy. The hCG-alpha levels, on the other hand, showed two distinct peaks, in the early period and at the term of pregnancy. (J.P.N.)

  1. Radioimmunoassay for mammalian type C viral reverse transcriptase

    International Nuclear Information System (INIS)

    Krakower, J.M.; Barbacid, M.; Aaronson, S.A.

    1977-01-01

    Radioimmunological techniques were applied to the analysis of reverse transcriptases of mammalian type C RNA viruses. The polymerase of Rauscher mouse leukemia virus was purified by ion exchange and sequential affinity chromatography. Radioimmunoassays that utilized the viral enzyme as a probe detected as little as 1 ng of purified polymerase. No cross-reactivity could be demonstrated between the reverse transcriptase and other known virus-coded proteins. By comparing the immunological reactivity of the purified enzyme with the reactivity of detergent-disrupted virions, Rauscher mouse leukemia virus was shown to contain the antigenic equivalent of 40 molecules of reverse transcriptase. In a homologous competition immunoassay, the Rauscher viral enzyme demonstrated type-specific antigenic determinants, which distinguish it from other mouse type C viral polymerases. In a broadly reactive interspecies immunoassay, the reverse transcriptases of a number of mammalian type C viruses were cross-reactive, indicating their shared antigenic determinants. Various treatments that inhibited or inactivated DNA polymerase activity had little or no effect on the immunological properties of the enzyme. Thus, radioimmunoassays should be useful in the search for type C viral reverse transcriptase as a marker of subviral expression

  2. Radioimmunoassay of plasma corticotropin in the edible Frog Rana esculenta L

    International Nuclear Information System (INIS)

    Vaudry, Hubert; Leboulenger, Francois; Dupont, Willy; Vaillant, Rene

    1975-01-01

    In the green Frog (Rana esculenta) the plasma contains a polypeptide immunologically related to human and porcine corticotropins. A radioimmunoassay capable of detecting 4.10 -12 g hog ACTH has been used for a direct plasma ACTH assay in the Frog. Using this method the ACTH rate was determined both in untreated frogs and in animals under various experimental conditions [fr

  3. Method for the optimum formation of angiotensin I from angiotensinogen and radioimmunoassay for angiotensin I

    International Nuclear Information System (INIS)

    Pagnucco, R.G.; Murty, D.R.; Muse, R.J.

    1978-01-01

    The invention deals with a method to optimize the formation of angiotensin I from angiotensinogens by optimizing the temperature, pH value and buffer system. Furthermore, the invention concerns a radioimmunoassay method to determine angiotensin I. Iodine 125 labelled angiotensin I is preferably used as tracer. (VJ) [de

  4. Pilot study on peptide purity—synthetic human C-peptide

    Science.gov (United States)

    Josephs, R. D.; Li, M.; Song, D.; Daireaux, A.; Choteau, T.; Stoppacher, N.; Westwood, S.; Wielgosz, R.; Xiao, P.; Liu, Y.; Gao, X.; Zhang, C.; Zhang, T.; Mi, W.; Quan, C.; Huang, T.; Li, H.; Melanson, J. E.; Ün, I.; Gören, A. C.; Quaglia, M.; Warren, J.

    2017-01-01

    Under the auspices of the Protein Analysis Working Group (PAWG) of the Comité Consultatif pour la Quantité de Matière (CCQM) a pilot study, CCQM-P55.2, was coordinated by the Bureau International des Poids et Mesures (BIPM) and the Chinese National Institute of Metrology (NIM). Four Metrology Institutes or Designated Institutes and the BIPM participated. Participants were required to assign the mass fraction of human C-peptide (hCP) present as the main component in the comparison sample for CCQM-P55.2. The comparison samples were prepared from synthetic human hCP purchased from a commercial supplier and used as provided without further treatment or purification. hCP was selected to be representative of the performance of a laboratory's measurement capability for the purity assignment of short (up to 5 kDa), non-cross-linked synthetic peptides/proteins. It was anticipated to provide an analytical measurement challenge representative for the value-assignment of compounds of broadly similar structural characteristics. The majority of participants used a quantitative nuclear magnetic resonance spectroscopy (qNMR) corrected for peptide impurities. Other participants provided results obtained by peptide impurity corrected amino acid analysis (PICAA) or elemental analysis (PICCHN). It was decided to assign reference values based on the KCRVs of CCQM-K115 for both the hCP mass fraction and the mass fraction of the peptide related impurities as indispensable contributor regardless of the use of PICAA, mass balance or any other approach to determine the hCP purity. This allowed participants to demonstrate the efficacy of their implementation of the approaches used to determine the hCP mass fraction. In particular it allows participants to demonstrate the efficacy of their implementation of peptide related impurity identification and quantification. The assessment of the mass fraction of peptide impurities is based on the assumption that only the most exhaustive and

  5. Radioimmunoassay of deoxynivalenol in wheat and corn

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Y.C.; Zhang, G.S.; Chu, F.S.

    With the availability of antibody against deoxynivalenol triacetate (DON-triacetate), a radioimmunoassay (RIA) for DON in wheat was developed. DON is extracted from the sample with acetonitrile-water defatted with hexane, and then reacted with acetic anhydride to form DON-triacetate. The reaction mixture is loaded onto a C-18 cartridge to remove excess reagents and impurities. Acetylated DON is eluted from the cartridge with 50% methanol in water, and then analyzed by radioimmunoassay utilizing antiserum against DON-triacetate and tritiated DON-triacetate. Overall recovery for DON added to wheat between 50 and 5000 ppb was 86% with a standard deviation of 7% and coefficient of variation of 8%. The limit of detection for DON was about 20 ppb. Analysis of 12 naturally contaminated wheat, corn, and mixed feed samples for DON revealed that RIA results agreed well with thin layer chromatographic analyses performed by other laboratories.

  6. Radioimmunoassay of TSH subunits in thyroid diseases and endocrine opthalmopahty

    International Nuclear Information System (INIS)

    Eder, W.

    1982-01-01

    Highly sensitive radioimmunoassays of hTSH sub-units were developed. The hormone preparations were labelled with 125-iodine according to a modified chloramine -T method, and purified by chromatography using biogel P6 and P60. Rabbit antisera were used as antibodies. Separation of the antibody-bound and of the free antigens was carried out via the double antibody method. The antiserum required for this purpose was obtained from a goat. The sensitivity of the assay was influenced by changing the protein content of the buffer, the incubation volume, the tracer amounts, the incubation time and the incubation temperature. For hTSH-α, the lowest detectable limit was found to be 50 pg/ml, for hTSH-#betta# 20 pg/ml. Thus, the sub-units could be determined for 98% of the patients under review. The #betta#-TSH radioimmunoassay is largely specific, TSH cross-reacts to a degree of 5%. The computerized evoluation was carried out by means of Spline approximation using the Siemens 4004 computer. Precision and accurateness are in compliance with generally accpted criteria. The serum levels of α and #betta# sub-units showed no discordancy with regard to TSH. In all groups of patients examined, the levels of the hormone-specific #betta#-chain were found to be exclusively dependent upon the actual thyroid activity. (orig.) [de

  7. Radioimmunoassay of prostaglandin F in plasma of pregnant women

    International Nuclear Information System (INIS)

    Albert, P.

    1980-01-01

    The aim of this dissertation was to determine quantitatively prostaglandin-F in the plasma of pregnant women in order to obtain further knowledge on changes in PG-F during pregnancy, in particular during the last three months. The plasma of women with clinically normal pregnancies was taken. Prior to radioimmunoassay the plasma was extracted (separation of PG from other plasma components) and chromatography carried out (group separation of PG). The efficiency of this process, as measured by the recovery rate of 3 H-PGF, lies between 60.99% and 93.01% for extraction and between 80.58% and 92.16% for chromatography. The plasma was extracted and analysed chromatographically for the assay. The radioimmunoassay was carried out according to the procedure recommended by the manufacturer. A calibration curve was produced without difficulty. The results of the examination of plasma samples were unsatisfactory because of the low sensitivity of the assay; PG-F values of the same order were obtained for all weeks of pregnancy. (orig./MG) [de

  8. Radioimmunoassay of chorionic gonadotropin in the diagnosis of ectopic pregnancy

    International Nuclear Information System (INIS)

    Skalba, P.; Grochal, A.; Kokocinska, D.; Parylak, H.

    1977-01-01

    The applicability of radioimmunoassay of the chorionic gonadotropins (HCG) was studied considering the diagnosis of ectopic pregnancy. The radioimmunoassay technique was presented basing on personal anti HCG serum and HCG preparation (Serono). The technique of separation, based on solid phase was described. The technique is not fully specific, permits, nevertheless to determine the serum hormone concentrations ranging over 0.4 μg per ml. The investigations were carried in 26 cases to tubal pregnancy and in 22 unpregnant women - where basing on the initial diagnosis and clinical observations, ectopic pregnancy was suspected. Moreover the serum HCG was established in 64 women in recent intrauterine pregnancy - lasting 3 to 8 weeks. The mean serum HCG concentration in cases of ectopic pregnancy was 5.4 μg per ml and was significantly lower than in cases of 4 weeks lasting intrauterine gestation. The presence of HCG was demonstrated in all cases of real ectopic gestations, it was absent in the compared group of the suspected, but unpregnant, subjects. The paper suggests that the presented method can be applied for the differential diagnosis of ectopic pregnancy and permits to plan the further clinical procedures. (author)

  9. The clinical significance of detecting serum glutamic acid decarboxylase antibody (GAD), C-peptide and insulin in diabetics

    International Nuclear Information System (INIS)

    Zheng Tingliang; Zhang Jinchi; Yao Yingfei; Chen Linxing; Huang Hua

    2005-01-01

    Objective: To explore the clinical significance of detecting serum glutamic acid decarboxylase (GAD) antibody, C-peptide (CP) and insulin (INS) in the classification of diabetic patients. Methods: Serum GAD antibody, CP and INS concentration were determined with RIA in 27 patients with type 1 diabetes mellitus (DM1) and 49 patients with type 2 diabetes mellitus (DM2). Sugar-electrode-method was used to detect the concentrations of fasting plasma glucose (FPG) in these patients. Results: The positive rate of GAD antibody in DM1 patients (66.7%) were significantly higher than that in DM2 group (8.2%) (P<0.01), The levels of CP and INS were lower in DM1 group than those in DM2 group as well (P<0.01). Conclusion: GAD antibody is a valuable marker to predict the impairment of β-cell GAD antibody levels, together with CP /FPG and INS/FPG ratios, might be useful in determining the type of DM and guiding the therapy. (authors)

  10. Significance and radioimmunoassay of gastric inhibitory polypeptide

    International Nuclear Information System (INIS)

    Zheng Ping; Zeng Minde; Yuan Jimin

    1995-01-01

    We have established the GIP Radioimmunoassay which has high sensitivity and specificity by labelling with iodogen and purified with HPLC. Using this method, the plasma GIP level was measured in 64 cases of which there are 10 normal individuals, 25 cases of diabetes and 29 cases of liver cirrhosis . The results showed that the plasma GIP level was significantly increased in patients with liver cirrhosis and correlated to degree of glucose tolerance damage

  11. Radioimmunoassay of peptide hormones using polyethyleneglycol, 2

    International Nuclear Information System (INIS)

    Ito, Yoshinori; Kikuchi, Akira; Inabe, Seijiro; Yabuuchi, Shinji; Kihara, Akira

    1975-01-01

    The radioimmunoassay (RIA) of glucagon was performed using 125 I in combination with polyethyleneglycol (PEG). In order to define the concentration of glucagon, the reaction time, the temperature and separation of F/B, the effects of the addition of various amounts of serum were studied. This method was found to be applicable, because of its reliability, simplicity, economy, and the shortness of the second reaction time. (Namekawa, K.)

  12. Radioimmunoassay of measles virus antibodies in SSPE

    International Nuclear Information System (INIS)

    Jankowski, M.A.; Gut, W.; Kantoch, M.

    1982-01-01

    A sensitive radioimmunoassay (RIA) was introduced for detecting measles virus IgG and IgM antibodies. The hyperimmune response to the measles virus could be demonstrated more accurately by RIA than by haemagglutination inhibition (HI). The ratio between RIA and HI antibody titres was decidedly higher in sera and cerebrospinal fluids of patients with subacute sclerosing panencephalitis than in those of other groups tested. (author)

  13. Radioimmunoassay of parathyroid hormone: past and future

    International Nuclear Information System (INIS)

    Yalow, R.S.

    1986-01-01

    In this report on radioimmunoassay of parathyroid hormone (iPTH) it was shown that the rate of disappearance of iPTH from plasma differed markedly in patients with primary hyperthyroidism or those with uremia and secondary hyperparathyroidism and that for each patient the rate of disappearance depended on the antiserum used for assay. The heterogeneity of iPTH in plasma was soon rapidly confirmed in many laboratories. (Auth.)

  14. A radioimmunoassay for urinary and serum dexamethasone

    International Nuclear Information System (INIS)

    Gilliland, J.M.; Morris, H.A.

    1986-01-01

    A radioimmunoassay suitable for measuring dexamethasone concentrations in serum and urine specimens following the low dose dexamethasone suppression test (0.25-1.0 mg dexamethasone) is reported. The assay has a sensitivity of 0.26 nmol/L, a between-assay coefficient of variation (CV) for dexamethasone concentrations between 1.15 and 15.40 nmol/L ranging from 11.7 - 5.5% and recoveries of 91 - 103%. (author)

  15. Islet Cell Associated Autoantibodies and C-Peptide Levels in Patients with Diabetes and Symptoms of Gastroparesis.

    Science.gov (United States)

    Siraj, Elias S; Homko, Carol; Wilson, Laura A; May, Patrick; Rao, Ajay D; Calles, Jorge; Farrugia, Gianrico; Hasler, William L; Koch, Kenneth L; Nguyen, Linda; Snape, William J; Abell, Thomas L; Sarosiek, Irene; McCallum, Richard W; Pasricha, Pankaj J; Clarke, John; Tonascia, James; Hamilton, Frank; Parkman, Henry P

    2018-01-01

    Individuals with diabetes are at increased risk for complications, including gastroparesis. Type 1 diabetes mellitus (T1DM) is an autoimmune disorder resulting in decreased beta-cell function. Glutamic acid decarboxylase-65 antibody (GADA) is the most commonly used test to assess autoimmunity while C-peptide level is used to assess beta-cell function. Patients with type 2 diabetes mellitus (T2DM), who are GADA positive, are labeled latent autoimmune diabetes in adults (LADA). To characterize patients with T1 and T2DM who have symptoms of gastroparesis using GADA and C-peptide levels and to look for association with the presence of gastroparesis and its symptom severity. 113 T1DM and 90 T2DM patients with symptoms suggestive of gastroparesis were studied. Symptom severity was assessed using Gastroparesis Cardinal Symptom Index (GCSI). Serum samples were analyzed for GADA and C-peptide. Delayed gastric emptying was present in 91 (81%) of T1DM and 60 (67%) of T2DM patients ( p  = 0.04). GADA was present in 13% of T2DM subjects [10% in delayed gastric emptying and 20% in normal gastric emptying ( p  = 0.2)]. Gastric retention and GCSI scores were mostly similar in GADA positive and negative T2DM patients. GADA was present in 45% of T1DM subjects [46% in delayed gastric emptying and 41% in normal gastric emptying ( p  = 0.81)]. Low C-peptide levels were seen in 79% T1DM patients and 8% T2DM. All seven T2DM patients with low C-peptide were taking insulin compared to 52% of T2DM with normal C-peptide. GADA was present in 13% while low C-peptide was seen in 8% of our T2DM patients with symptoms of gastroparesis. Neither did correlate with degree of delayed gastric emptying or symptom severity. NCT01696747.

  16. Preserved C-peptide levels in overweight or obese compared with underweight children upon diagnosis of type 1 diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Hyeoh Won Yu

    2015-06-01

    Full Text Available PurposeWe hypothesized that overweight or obese children might develop type 1 diabetes mellitus (T1DM early despite residual beta-cell function. Factors independently associated with preservation of C-peptide level were analyzed.MethodsWe retrospectively reviewed the medical data of 135 children aged 2.1-16.5 years with autoimmune T1DM. Body mass index (BMI, pubertal stage, and glycosylated hemoglobin (HbA1c and C-peptide levels were evaluated. Patients were assigned to underweight (22.2%, normal weight (63.7%, and overweight or obese (14.1% groups according to their BMI.ResultsPreservation of serum C-peptide levels (≥0.6 ng/mL was found in 43.0% of subjects. With increasing BMI, the proportions of children with preserved C-peptide levels increased from 33.3% to 41.9% to 63.2%, with marginal significance (P=0.051. Interaction analysis indicated no effect of BMI score on age at onset associated with serum C-peptide levels. The lower the C-peptide level, the younger the age of onset (P<0.001, after adjustment for BMI z-score and HbA1c level. However, no significant relationship between BMI z-score or category and onset age was evident. Upon multivariate-adjusted modeling, the odds that the C-peptide level was preserved increased by 1.2 fold (P=0.001 per year of life, by 3.1 folds (P=0.015 in children presenting without (compared to with ketoacidosis, and by 5.0 folds (P=0.042 in overweight or obese (compared to underweight children.ConclusionOverweight or obese children had slightly more residual beta-cell function than did underweight children. However, we found no evidence that obesity temporally accelerates T1DM presentation.

  17. Development of SAAP3D force field and the application to replica-exchange Monte Carlo simulation for chignolin and C-peptide

    Science.gov (United States)

    Iwaoka, Michio; Suzuki, Toshiki; Shoji, Yuya; Dedachi, Kenichi; Shimosato, Taku; Minezaki, Toshiya; Hojo, Hironobu; Onuki, Hiroyuki; Hirota, Hiroshi

    2017-12-01

    Single amino acid potential (SAAP) would be a prominent factor to determine peptide conformations. To prove this hypothesis, we previously developed SAAP force field for molecular simulation of polypeptides. In this study, the force field was renovated to SAAP3D force field by applying more accurate three-dimensional main-chain parameters, instead of the original two-dimensional ones, for the amino acids having a long side-chain. To demonstrate effectiveness of the SAAP3D force field, replica-exchange Monte Carlo (REMC) simulation was performed for two benchmark short peptides, chignolin (H-GYDPETGTWG-OH) and C-peptide (CHO-AETAAAKFLRAHA-NH2). For chignolin, REMC/SAAP3D simulation correctly produced native β-turn structures, whose minimal all-atom root-mean-square deviation value measured from the native NMR structure (except for H) was 1.2 Å, at 300 K in implicit water, along with misfolded β-hairpin structures with unpacked aromatic side chains of Tyr2 and Trp9. Similar results were obtained for chignolin analog [G1Y,G10Y], which folded more tightly to the native β-turn structure than chignolin did. For C-peptide, on the other hand, the α-helix content was larger than the β content on average, suggesting a significant helix-forming propensity. When the imidazole side chain of His12 was protonated (i.e., [His12Hip]), the α content became larger. These observations as well as the representative structures obtained by clustering analysis were in reasonable agreement not only with the structures of C-peptide that were determined in this study by NMR in 30% CD3CD in H2O at 298 K but also with the experimental and theoretical behaviors having been reported for protonated C-peptide. Thus, accuracy of the SAAP force field was improved by applying three-dimensional main-chain parameters, supporting prominent importance of SAAP for peptide conformations.

  18. Diurnal Variations in Serum Glucose, Insulin and C-Peptide of Normal Korean Adults

    International Nuclear Information System (INIS)

    Choi, Du Hyok; Chung, June Key; Lee, Hong Kyu; Koh, Chang Soon; Hong, Kee Suk

    1983-01-01

    It is already well known that many factors are involved in maintaining normal blood glucose level. The amount and components of meal are also thought to be some of the factors which affect the blood glucose and insulin levels. It is reported that as for Koreans sugar takes up over 75% out of 2,098 kcal, the average daily calorie intake per adult. It implies that Koreans take a high-sugar diet compared with Westerners who take 40-50% of sugar out of their total average daily calorie. For the purpose of studying diurnal variations in serum glucose, insulin and C-peptide of normal Koreans adults based on ordinary Korean diet, we selected 13 normal Korean male adults and divided them into two groups, Group I (7 persons) and Group II (6 persons). We put Group I on 3,100 kcal and 75% sugar diet, and Group II on 2,100 kcal and 69% sugar diet per day for over 4 days. Serum glucose, insulin and C-peptide were checked every 30 minutes or every hour throughout 2 hour. Results are as follows: 1. As for serum glucose level, in the preprandial fasting state in the morning, mean±S.D. of Group I was 91.1±3.2 mg%, while that of Group II is 82.5±4.4 mg%. Both groups showed peaks of increased glucose level t postprandial 1 hour after each meal. The peak returned to the level shown during the fasting state at postprandial 1 hour after breakfast while the relatively high glucose levels were maintained respectively even for 2 or 3 hours after lunch and dinner. 2. As for serum insults level, Group I showed mean±S.D. of 14.7±3.0 μU/ml while Group II shows that of 7.0±2.6 μU/ml in the fasting state. Group I particularly showed the largest peak from preprandial a half or one and half an hour to postprandial one hour of lunch, and made relatively small peaks (47.7±10.8 μU/ml) at postprandial 1 hour after breakfast and dinner. No such large peak was marked in Group II, though it showed relatively similar patterns of peak after each meal. 3. As for C-peptide, in the fasting state

  19. 18F-Labeled proinsulin connecting peptide (C-peptide): In vivo distribution and pharmacokinetics using PET

    International Nuclear Information System (INIS)

    Fredriksson, A.; Stone-Elander, S.; Ekberg, K.; Ingvar, M.; Wahren, J.; Johansson, B.-L.

    2002-01-01

    C-peptide, produced and released in equimolar amounts with insulin, was previously considered biologically inactive. Administration to type 1 (insulin-dependent) diabetes mellitus (DM) patients has, however, indicated that C-peptide exerts a number of beneficial effects, improving long-term complications of type 1 DM on e.g. renal and nerve function (Wahren, Am J Physiol Endocrinol Metab 278: E759, 2000). Aim: To evaluate biodistribution and regional pharmacokinetics in humans using the 18 F-labeled C-peptide and positron emission tomography. Materials and Methods: Five, fasting, male IDDM patients were scanned after injection of N-4-[ 18 F]fluorobenzoyl-C-peptide. Dynamic scans over kidneys (4 pat: 2 no-carrier-added (n.c.a.); 2 carrier C-peptide added (c.a.)) and heart (1 pat, n.c.a) and static scans (n.c.a) over body segments (2 pat), CNS and urinary bladder were performed. Plasma radioactivity was also measured. Results: PET images showed predominant distribution of radioactivity to the kidneys (renal cortex 7% of injected dose (i.d.) at peak). Distinguishable amounts of radioactivity were also observed in heart, lungs and liver, but not in CNS at late times. Low amounts were observed in what was presumed to be pancreas. Uptake in total muscle, based on concentrations in a skeletal muscle ROI at 10-75 min, could account for up to 15% i.d. Radioactivity was excreted to the urinary bladder. Time-radioactivity curves for renal cortex peaked within the first 6 min and then decreased to ca 0.01±0.002% i.d./mL at 15 min. Radioactivity peaked in the second time frame (≤ 4 min) in liver and in the first time frame (≤ 2 min) in other organs and plasma. Washout for all organs and for plasma was biphasic. The kinetics in the renal cortex were different when carrier C-peptide was co-injected. Conclusion: The main distribution to the kidneys observed here is consistent with previous findings on C-peptide's catabolism and it's documented effects on renal function. This

  20. Iodine labelled pyrethroids, their chemical preparation and their application to radioimmunoassays. Pyrethrinoides marques a l'iode, leur procede de preparation et leur application aux dosages radioimmunologiques

    Energy Technology Data Exchange (ETDEWEB)

    Demoute, J.P.; Touer, G.; Mouren, M.

    1987-07-31

    This invention deals with iodine 125 or iodine 131 labelled pyrethroids, their chemical preparations and their application to radioimmunoassay for the determination of pyrethroids (deltamethrin) in human, or animal body fluids.

  1. Radioimmunoassay of aldosterone and its level in plasma and urine

    International Nuclear Information System (INIS)

    Putz, Z.; Hampl, R.; Veleminsky, J.; Starka, L.

    1981-01-01

    A method of plasma and urine aldosterone radioimmunoassay is described and evaluated. Highly specific antisera were obtained through rabbit immunization using partly aldosterone-18,21-dihemisuccinate-BSA, partly aldosterone-3-carboxymethyl-oxime-BSA, free of the 18-derivative. The use of a more specific antiserum against the 3-derivative permitted the determination to be performed immediately from the biological specimen extract. Hydrolysis with sulphuric acid in the presence of dichloromethane proved the most appropriate of the different techniques of releasing aldosterone-glucuronoside for the determination of the total urine hormone. The normal values (average +- 2 S. D.) of plasma aldosterone were 0.19 +- 0.067 nmol/l, those of the free urine hormone 0.918 +- 0.458 nmol/day, and the total urine aldosterone 15.3 +- 5.8 nmol/day. (author)

  2. Radioimmunoassay for bupropion in human plasma: comparison of tritiated and iodinated radioligands

    Energy Technology Data Exchange (ETDEWEB)

    Butz, R.F.; Smith, P.G.; Schroeder, D.H.; Findlay, J.W.

    1983-03-01

    We evaluated the potential usefulness of /sup 125/I-labeled p-hydroxybupropion in a direct radioimmunoassay for bupropion in human plasma as compared with a currently used (/sup 3/H)bupropion dextran-coated charcoal method. In both radioimmunoassay methods succinoylpropylbupropion antiserum was used that was highly specific for unchanged drug, cross reactivities with known bupropion metabolites being less than 0.3%. However, the use of /sup 125/I-labeled p-hydroxybupropion afforded greater sensitivity (0.3 microgram/L vs 0.6 microgram/L with (/sup 3/H)bupropion) and was readily adaptable to the more convenient polyethylene glycol separation method. Between-assay CVs were 3.8 to 12.2% (mean 7.6%) with the /sup 125/I-based radioimmunoassay and 5.1 to 11.5% (mean 7.5%) with the /sup 3/H-based assay. Agreement between the two radioimmunoassay determinations of buproprion in human plasma samples collected over a 60-h period after oral drug administration was excellent (slope . 1.086, r . 0.989). We find the /sup 125/I-based assay a convenient and suitable alternative to the (/sup 3/H)bupropion assay in pharmacokinetic studies in humans.

  3. Radioimmunoassay for bupropion in human plasma: comparison of tritiated and iodinated radioligands.

    Science.gov (United States)

    Butz, R F; Smith, P G; Schroeder, D H; Findlay, J W

    1983-03-01

    We evaluated the potential usefulness of 125I-labeled p-hydroxybupropion in a direct radioimmunoassay for bupropion in human plasma as compared with a currently used [3H]bupropion dextran-coated charcoal method. In both radioimmunoassay methods succinoylpropylbupropion antiserum was used that was highly specific for unchanged drug, cross reactivities with known bupropion metabolites being less than 0.3%. However, the use of 125I-labeled p-hydroxybupropion afforded greater sensitivity (0.3 microgram/L vs 0.6 microgram/L with [3H]bupropion) and was readily adaptable to the more convenient polyethylene glycol separation method. Between-assay CVs were 3.8 to 12.2% (mean 7.6%) with the 125I-based radioimmunoassay and 5.1 to 11.5% (mean 7.5%) with the 3H-based assay. Agreement between the two radioimmunoassay determinations of buproprion in human plasma samples collected over a 60-h period after oral drug administration was excellent (slope = 1.086, r = 0.989). We find the 125I-based assay a convenient and suitable alternative to the [3H]bupropion assay in pharmacokinetic studies in humans.

  4. Development and application of radioimmunoassay and enzyme immunoassays in microbiological and immunological diagnosis. 4

    International Nuclear Information System (INIS)

    Struy, H.; Horeschi, G.; Wolffgang, H.; Morenz, J.

    1982-01-01

    Indirect solid phase radioimmunoassays and enzyme immunoassays were developed for the quantitative determination of low concentrations of IgG, IgA, IgM, and IgE. PVC blister and microtiterplates of polystyrene with adsorptively bound purified immunoglobulins were used as carrier. The determination of the immunoglobulins was accomplished with a uniform system of indicators, which consists of class-specific antihuman immunoglobulin sera from rabbits and of labelled ( 125 I and horseradish peroxydase, resp.) antirabbitglobulin from sheep. The developped competitive radioimmuno- and enzyme immunoassays allows the determination of concentrations of classes of immunoglobulins down to nearly 1 ng/ml, and the indirect sandwich solid phase radioimmunoassay determinations of IgE down to about 1 IU/ml. The values of IgG determined in liquors and those of IgE found in sera correspond very well to values which were measured with commercial kits. (author)

  5. A dietary pattern that is associated with C-peptide and risk of colorectal cancer in women.

    Science.gov (United States)

    Fung, Teresa T; Hu, Frank B; Schulze, Matthias; Pollak, Michael; Wu, Tianying; Fuchs, Charles S; Giovannucci, Edward

    2012-06-01

    Higher serum C-peptide concentrations have shown to be associated with an increased risk of colorectal cancer (CRC). Therefore, we used diet information to identify food groups that correlated with fasting serum concentrations of C-peptide and assess the association of this dietary pattern and CRC risk. Major food contributors to fasting C-peptide concentrations were identified with stepwise linear regression in a subsample (n = 833) of women from a large cohort. We then summed the consumption frequency of the major food contributors to form a C-peptide dietary pattern for the entire cohort (n = 66,714). Risk for CRC was computed using Cox proportional hazard model with the C-peptide dietary pattern score as the predictor. In up to 20 years of follow-up, we ascertained 985 cases of CRC and 758 colon cancer. After adjusting for confounders, the C-peptide dietary pattern, characterized by higher meat, fish, and sweetened beverage intake, but lower coffee, high fat dairy, and whole grains intake, showed direct association with CRC risk (RR comparing extreme quintiles = 1.29, 95 % CI = 1.05-1.58, p trend = 0.048). The same comparison was slightly stronger for colon cancer (RR = 1.35, 95 % CI = 1.07-1.70, p trend = 0.009). In stratified analysis, there was no association between the C-peptide dietary pattern and colon cancer among lean and active women. However, for overweight or sedentary women, RR for the same comparison was 1.58 (95 % CI = 1.20-2.07, p trend = 0.002) (p for interaction = 0.007). We derived a dietary pattern that correlated with C-peptide concentrations. This pattern was associated with an increase in colon cancer, especially among women who were overweight or sedentary.

  6. Solid phase separation technique for use in radioimmunoassays

    International Nuclear Information System (INIS)

    Tu, J.I.

    1979-01-01

    A radioimmunoassay procedure, and article of manufacture for carrying out that procedure, are disclosed herein. The solid phase separation technique utilized in the radioimmunoassay of this invention utilizes a test tube, the internal surface of which has been coated with two antibody layers

  7. Transfer of estradiol to human milk. [Radioimmunoassay

    Energy Technology Data Exchange (ETDEWEB)

    Nilsson, S.; Nygren, K.G.; Johansson, E.D.B.

    1978-11-15

    A radioimmunoassay for the measurement of estradiol in human milk is evaluated. The detection limit was found to be 25 pg of estradiol per milliliter of milk. In milk samples collected from four lactating women during three to four months and from one pregnant and lactating woman, the concentration of estradiol was found to be below the detection limit of the assay. When six lactating women were given vaginal suppositories containing 50 or 100 mg of estradiol, it was possible to estimate the estradiol concentration in milk. A ratio of transfer of estradiol from plasma to milk during physiologic conditions is calculated to be less than 100 : 10.

  8. Solid phase double-antibody radioimmunoassay procedure

    International Nuclear Information System (INIS)

    Niswender, G.D.

    1977-01-01

    The present invention is concerned with the radioimmunoassay (RIA) procedure for assaying body fluid content of an antigenic substance which may either be an antigen itself or a hapten capable of being converted, such as by means of reaction with a protein, to an antigenic material. The present invention is concerned with a novel and improved modification of a double-antibody RIA technique in which there is a first antibody that is specific to the antigenic substance suspected to be present in a body fluid from which the assay is intended. The second antibody, however, is not specific to the antigenic substance or analyte, but is an antibody against the first antibody

  9. Radioimmunoassay in the diagnosis of fascioliasis

    International Nuclear Information System (INIS)

    Tomanek, J.; Willomitzer, J.; Chroustova, E.

    1978-01-01

    The objective of the study was to develop a sensitive and specific radioimmunoassay (RIA) method for the diagnosis of F. hepatica infection that would be convenient to use in examining large numbers of samples. The main problem was the preparation of a suitable antigen or specific fraction, since the crude extract of adult Fasciola hepatica is a heterogeneous mixture of somatic, metabolic and host substances with possible nonspecific antigenic properties. The antigen was a protein fraction separated from crude extract of adult F. hepatica by gel filtration and labelled with 125 iodine. (T.I.)

  10. Radioimmunoassay procedure using a stabilized complex

    International Nuclear Information System (INIS)

    Sultanian, I.V.; Irani, J.H.

    1978-01-01

    An improved radioimmunoassay procedure involves the use of a stabilized complex of labelled antigen and antibody which has an extended shelf life as compared to the same complex absent the stabilizers. Since the time needed to incubate the mixture of labelled antigen and antibody is eliminated, the time for completing the assay is considerably shortened and simplified. The components for carrying out the procedure are packaged in a kit basically including standard antigen for generation of a standard curve, a stabilized labelled antigen-antibody complex and reference serum, if used. A plurality of stabilizers are used in the complex to provide a shelf life of six weeks or more. 10 claims

  11. Radioimmunoassay of nortestosterone and related steroids

    International Nuclear Information System (INIS)

    Hampl, R.; Starka, L.; Picha, J.; Chundela, B.

    1979-01-01

    A radioimmunoassay of nortestosterone and related steroids, including its principal metabolites, is described and evaluated. Antisera against nortestosterone-17β-hemisuccinate- and nortestosterone-3-carboxymethyloxime-bovine serum albumin were raised in goats. By using a mixture of such antisera with different selectivity, the cross-reactions of several naturally occuring steroids can be reduced. The method can be applied for the detection of nortestosterone in both unprocessed or hydrolyzed urine extracts and also in plasma. It has been used as a screening test for anabolics in doping control. (orig.) [de

  12. Radioimmunoassay of digoxigenin glycosides in Digitalis lanata

    International Nuclear Information System (INIS)

    Lehtola, T.; Hiltunen, R.; Schantz, M. v.; Huhtikangas, A.

    1981-01-01

    Radioimmunoassay (RIA) has been used in the analysis of digoxigenin glycoside contents of crude ethanolic extracts prepared from fresh leaf samples of Digitalis lanata EHRH. The commercial antidigoxin antiserum used in the assay was highly specific against the digoxigenin aglycone. Steroid derivatives with only slight structural differences from digoxigenin remained practically unassayed. The method is highly sensitive, and excellent values for accuracy, precision and correlation were obtained. Digoxigenin glycoside levels of second-year D. lanata leaves were found to be considerably higher than those of first-year leaves. (orig.)

  13. Key comparison study on peptide purity—synthetic human C-peptide

    Science.gov (United States)

    Josephs, R. D.; Li, M.; Song, D.; Westwood, S.; Stoppacher, N.; Daireaux, A.; Choteau, T.; Wielgosz, R.; Xiao, P.; Liu, Y.; Gao, X.; Zhang, C.; Zhang, T.; Mi, W.; Quan, C.; Huang, T.; Li, H.; Flatschart, R.; Borges Oliveira, R.; Melanson, J. E.; Ohlendorf, R.; Henrion, A.; Kinumi, T.; Wong, L.; Liu, Q.; Oztug Senal, M.; Vatansever, B.; Ün, I.; Gören, A. C.; Akgöz, M.; Quaglia, M.; Warren, J.

    2017-01-01

    Under the auspices of the Protein Analysis Working Group (PAWG) of the Comité Consultatif pour la Quantité de Matière (CCQM) a key comparison, CCQM-K115, was coordinated by the Bureau International des Poids et Mesures (BIPM) and the Chinese National Institute of Metrology (NIM). Eight Metrology Institutes or Designated Institutes and the BIPM participated. Participants were required to assign the mass fraction of human C-peptide (hCP) present as the main component in the comparison sample for CCQM-K115. The comparison samples were prepared from synthetic human hCP purchased from a commercial supplier and used as provided without further treatment or purification. hCP was selected to be representative of the performance of a laboratory's measurement capability for the purity assignment of short (up to 5 kDa), non-cross-linked synthetic peptides/proteins. It was anticipated to provide an analytical measurement challenge representative for the value-assignment of compounds of broadly similar structural characteristics. The majority of participants used a peptide impurity corrected amino acid analysis (PICAA) approach as the amount of material that has been provided to each participant (25 mg) is insufficient to perform a full mass balance based characterization of the material by a participating laboratory. The coordinators, both the BIPM and the NIM, were the laboratories to use the mass balance approach as they had more material available. It was decided to propose KCRVs for both the hCP mass fraction and the mass fraction of the peptide related impurities as indispensable contributor regardless of the use of PICAA, mass balance or any other approach to determine the hCP purity. This allowed participants to demonstrate the efficacy of their implementation of the approaches used to determine the hCP mass fraction. In particular it allows participants to demonstrate the efficacy of their implementation of peptide related impurity identification and quantification

  14. Radioimmunoassay techniques and reproductive management of livestock in North Africa

    International Nuclear Information System (INIS)

    Lahlou-Kassi, A.; Lakhdissi, H.

    1984-01-01

    The report summarizes the principal applications of progesterone radioimmunoassay (P 4 -RIA) in Morocco for evaluating and improving fertility in cattle, sheep and camels. In cattle, P 4 -RIA of blood or milk helped to determine the time for onset of sexual functions after parturition and the incidence of silent oestrus. It is especially important to assess the first factor in semi-extensively managed herds, while the second factor occurs mainly in intensively managed herds. P 4 -RIA is an important tool in fertility improvement programmes involving induction and synchronization of oestrus and testing for early pregnancy. In sheep, P 4 -RIA helped to define the optimum age at first mating of ewe lambs and the optimum mating season of the year for adult ewes. In camels, analysis of the profile of plasma progesterone before and after mating suggests that P 4 -RIA could be used for early pregnancy testing. (author)

  15. Radioimmunoassay for prostatic acid phosphatase in human serum. Methodologic aspects

    International Nuclear Information System (INIS)

    Pradalier, N.; Canal, P.; Pujol, A.; Fregevu, Y.; Soula, G.

    1982-01-01

    We propose a double antibody radioimmunoassay for human prostatic acid phosphatase (PAP) in serum for diagnosis and management of prostatic adenocarcinoma under treatment. The antigen is purified from human prostatic fluid by a gel-filtration on Sephadex G 100 followed by affinity chromatography on Con A Sepharose. A specific antibody is raised in rabbits and purified by immunoadsorption with a female serum. The described technique offers both radioisotopic sensibility and immunologic specificity. Physiological values determined in the serum of 125 healthy males are below 2 ng/ml. No significative differences are observed with age. The proposed technique also shows significant differences between values evaluated for benign prostatic hyperplasia and prostatic adenocarcinoma [fr

  16. Radioimmunoassay of paralytic shellfish toxins in clams and mussels

    International Nuclear Information System (INIS)

    Yang, G.C.; Imagire, S.J.; Yasaei, P.; Ragelis, E.P.; Park, D.L.; Page, S.W.; Carlson, R.E.; Guire, P.E.

    1987-01-01

    Shellfish contaminated with paralytic shellfish poisons (PSP) compromise human health. The threat of this contamination results in enormous economic losses in the recreational and commercial exploitation of shellfish resources in the affected areas. Most states deal with the PSP problem either by prohibiting the collection of shellfish during certain time periods or by instituting monitoring programs. The only recognized method of analysis for PSP that is currently and routinely used in monitoring programs is the time-of-death mouse bioassay. Several attempts to develop simple and highly specific biochemical assays for the detection and quantitation of the PSP toxins have been reported. More recently, much improved immunoassays have been developed. To evaluate the validity and usefulness of the immunoassay for the determination of PSP toxins, the authors have used extracts of shellfish gathered from Maine and Connecticut to compare the results of the mouse bioassay and HPLC methods with the radioimmunoassay developed previously

  17. Performance of various mathematical methods for calculation of radioimmunoassay results

    International Nuclear Information System (INIS)

    Sandel, P.; Vogt, W.

    1977-01-01

    Interpolation and regression methods are available for computer aided determination of radioimmunological end results. We compared the performance of eight algorithms (weighted and unweighted linear logit-log regression, quadratic logit-log regression, Rodbards logistic model in the weighted and unweighted form, smoothing spline interpolation with a large and small smoothing factor and polygonal interpolation) on the basis of three radioimmunoassays with different reference curve characteristics (digoxin, estriol, human chorionic somatomammotropin = HCS). Great store was set by the accuracy of the approximation at the intermediate points on the curve, ie. those points that lie midway between two standard concentrations. These concentrations were obtained by weighing and inserted as unknown samples. In the case of digoxin and estriol the polygonal interpolation provided the best results while the weighted logit-log regression proved superior in the case of HCS. (orig.) [de

  18. Anti-DNA antibody in serum measured by radioimmunoassay (Farr technique)

    International Nuclear Information System (INIS)

    Manthorpe, R.; Palit, J.; Bendixen, G.

    1978-01-01

    Anti-DNA antibody determination in serums is increasingly used because it supports the diagnosis of systemic lupres erythematosus (SLE) with high selectivity. The present work evaluates several of the technical variables of the Farr radioimmunoassay for anti-DNA antibody determination and describes a recommendable procedure, emphasizes the most important sources of error and gives the range of normal blood donors and a group of hospital patients without SLE. (author)

  19. C peptide and insulin releasing RIA test for the investigation of β cell function in diabetic patients

    International Nuclear Information System (INIS)

    Shi Ailan; Zhu Chengmo; Wang Qiyu; Wang Ping

    1993-01-01

    Results of C-peptide releasing RIA test in 15 normals, and 100 diabetes were summarized and compared with glucose tolerance test and serum insulin for investigating the characteristics in different types of diabetes and evaluating the functional state of islet β cell. In 36 cases of IDDM the fasting blood sugar was significantly increased, and further elevated after eating of bread, but its peak time delay in 2 hours (normalin 1 hour). The level of basal C-peptide is very low, but shows slightly weak on no response after bread stimulating test, all of this denotes that β cell function of islets severely injured. The increasing of fasting blood sugar in 64 cases of NIDDM was lower than those of IDDM. Fasting C-peptide and insulin was normal or increased, their peak value increased after bread stimulation with peak time delayed also at 2 hours. Above results demonstrated that the function of islets B cell decreased but not fully deprived. It is concluded that C-peptide and insulin stimulating test, together with OGTT can accurately assess the islets β cell function, and also have important significance in the pathogenesis, classification and staging, prognostic evaluation and monitoring of therapeutic effects in diabetes

  20. C-Peptide Versus Insulin: Relationships with Risk Biomarkers of Cardiovascular Disease in Metabolic Syndrome in Young Arab Females

    Directory of Open Access Journals (Sweden)

    A. Abdullah

    2012-01-01

    Full Text Available Background. Obesity is a major health concern and is associated with metabolic syndrome (MetS that increases the risk for cardiovascular disease (CVD. Since little is known about the relationships between MetS components and CVD in overweight/obese young Arab females, our study aimed at examining these relationships and further to explore the associations between connecting peptide (C-peptide and insulin with these biomarkers. Subjects and Methods. In this cross-sectional study, 80 apparently healthy young Arab females were recruited and grouped by their body mass index (BMI into normal-weight (GI and overweight/obese (GII groups. Results. The two groups significantly differed in BMI, waist circumference (WC and values of biomarkers, namely, leptin, fasting insulin, uric acid (UA, insulin resistance (HOMA-IR, C-peptide, high-sensitivity C-reactive protein (hs-CRP, high-density lipoprotein cholesterol (HDL-C, systolic blood pressure (SBP, and diastolic blood pressure (DBP. C-peptide significantly correlated with WC, leptin, UA, and HDL-C and was predicted by three biomarkers; UA, WC and HDL-C. Whereas, insulin significantly correlated with only two biomarkers including leptin and DBP and was predicted by UA and DBP. Conclusions. The present study highlighted the association between MetS and CVD in young Arab females and the possible role of C-peptide in the prediction of CVD.

  1. Changes in Bone Alkaline Phosphatase and Procollagen Type-1 C-Peptide after Static and Dynamic Exercises

    Science.gov (United States)

    Kubo, Keitaro; Yuki, Kazuhito; Ikebukuro, Toshihiro

    2012-01-01

    We investigated the effects of two types of nonweight-bearing exercise on changes in bone-specific alkaline phosphatase (BAP) and pro-collagen type 1 C-peptide (P1P). BAP is a specific marker of bone synthesis, whereas P1P reflects synthesis of type 1 collagen in other organs as well as bone. Eight participants performed static and dynamic…

  2. New Solid Phases for Estimation of Hormones by Radioimmunoassay Technique

    International Nuclear Information System (INIS)

    Sheha, R.R.; Ayoub, H.S.M.; Shafik, M.

    2013-01-01

    The efforts in this study were initiated to develop and validate new solid phases for estimation of hormones by radioimmunoassay (RIA). The study argued the successful application of different hydroxy apatites (HAP) as new solid phases for estimation of Alpha fetoprotein (AFP), Thyroid Stimulating hormone (TSH) and Luteinizing hormone (LH) in human serum. Hydroxy apatites have different alkali earth elements were successfully prepared by a well-controlled co-precipitation method with stoichiometric ratio value 1.67. The synthesized barium and calcium hydroxy apatites were characterized using XRD and Ftir and data clarified the preparation of pure structures of both BaHAP and CaHAP with no evidence on presence of other additional phases. The prepared solid phases were applied in various radioimmunoassay systems for separation of bound and free antigens of AFP, TSH and LH hormones. The preparation of radiolabeled tracer for these antigens was carried out using chloramine-T as oxidizing agent. The influence of different parameters on the activation and coupling of the used apatite particles with the polyclonal antibodies was systematically investigated and the optimum conditions were determined. The assay was reproducible, specific and sensitive enough for regular estimation of the studied hormones. The intra-and inter-assay variation were satisfactory and also the recovery and dilution tests indicated an accurate calibration. The reliability of these apatite particles had been validated by comparing the results that obtained by using commercial kits. The results finally authenticates that hydroxyapatite particles would have a great potential to address the emerging challenge of accurate quantitation in laboratory medical application

  3. Increased specificity of plasma glucagon radioimmunoassay by use of acetone extraction

    International Nuclear Information System (INIS)

    Schenck, H. von

    1983-01-01

    The specificity of glucagon determinations by radioimmunoassay with two pancreatic-type glucagon antisera has been determined by means of gel permeation chromatography before and after treatment of human plasma with acetone and ethanol. Acetone precipitates the high molecular mass substances which interfere with the antisera directed against the carboxyl-terminal region of the glucagon molecule and applied in the radioimmunoassay, and which are apparent in the void volume and cross-reacting precursor fragments, while pancreatic glucagon is extracted to slightly more than 50%. Hence acetone treatment is suggested as a suitable means of obtaining specific glucagon results in single samples. Ethanol also precipitates the high molecular mass substances, but partly extracts the precursor fragments in addition to the glucagon. Ethanol treatment is therefore suggested for chemical diagnosis of the glucagonoma syndrome in which the tumor often produces precursor fragments. (Auth.)

  4. Socioecological correlates of energy balance using urinary C-peptide measurements in wild female mountain gorillas.

    Science.gov (United States)

    Grueter, Cyril C; Deschner, Tobias; Behringer, Verena; Fawcett, Katie; Robbins, Martha M

    2014-03-29

    Maintaining a balanced energy budget is important for survival and reproduction, but measuring energy balance in wild animals has been fraught with difficulties. Female mountain gorillas are interesting subjects to examine environmental correlates of energy balance because their diet is primarily herbaceous vegetation, their food supply shows little seasonal variation and is abundant, yet they live in cooler, high-altitude habitats that may bring about energetic challenges. Social and reproductive parameters may also influence energy balance. Urinary C-peptide (UCP) has emerged as a valuable non-invasive biomarker of energy balance in primates. Here we use this method to investigate factors influencing energy balance in mountain gorillas of the Virunga Volcanoes, Rwanda. We examined a range of socioecological variables on energy balance in adult females in three groups monitored by the Karisoke Research Center over nine months. Three variables had significant effects on UCP levels: habitat (highest levels in the bamboo zone), season (highest levels in November during peak of the bamboo shoot availability) and day time (gradually increasing from early morning to early afternoon). There was no significant effect of reproductive state and dominance rank. Our study indicates that even in species that inhabit an area with a seemingly steady food supply, ecological variability can have pronounced effects on female energy balance. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Radioiodinated derivatives for steroid radioimmunoassay. Application to the radioimmunoassay of cortisol

    International Nuclear Information System (INIS)

    Gomez-Sanchez, C.; Milewich, L.; Holland, O.B.

    1977-01-01

    Gamma-emitting steroid tracers for use in the radioimmunoassay of steroids have a number of advantages over the more common tritiated tracers. The steroid derivatives aldosterone-3-(p-hydroxybenzoyl) hydrazone, aldosterone-3-(p-hydroxyphenylpropionyl)hydrazone, deoxycorticosterone-3-(p-hydroxyphenylpropionyl)hydrazone, and cortisol-3-(p-hydroxyphenylpropionyl)hydrazone were synthesized by a one-step procedure and iodinated ([ 125 I]). To illustrate the usefulness of these derivatives, we describe the details of a cortisol radioimmunoassay. The use of the radioiodinated tracer appeared to increase the specificity of the antigen-antibody reaction when compared with [ 3 H]cortisol. The methodology involved in the preparation of the steroid derivatives described above can be extended to other 3-oxo-4-ene-containing steroids, with the advantages of economy, simplicity, and versatility

  6. Interferences in radioimmunoassay of aflatoxins in food and fodder samples of plant origin

    International Nuclear Information System (INIS)

    Rauch, P.; Fukal, L.; Brezina, P.; Kas, J.

    1988-01-01

    Cross-reactions and resulting nonspecific binding of substances with structures resembling aflatoxins (derivatives of coumarin, and cinnamonic and benzoic acids, etc.) were investigated. The concentrations of these substances causing erroneously high or false positive values in radioimmunoassay were determined. One μg aflatoxin B 1 /kg sample may be simulated by the occurrence of 5 g coumarin, 10 g caffeic acid, 16 g chlorogenic acid, or 15 g vanillin/kg fodder or food sample

  7. Interferences in radioimmunoassay of aflatoxins in food and fodder samples of plant origin

    Energy Technology Data Exchange (ETDEWEB)

    Rauch, P.; Fukal, L.; Brezina, P.; Kas, J.

    Cross-reactions and resulting nonspecific binding of substances with structures resembling aflatoxins (derivatives of coumarin, and cinnamonic and benzoic acids, etc.) were investigated. The concentrations of these substances causing erroneously high or false positive values in radioimmunoassay were determined. One ..mu..g aflatoxin B/sub 1//kg sample may be simulated by the occurrence of 5 g coumarin, 10 g caffeic acid, 16 g chlorogenic acid, or 15 g vanillin/kg fodder or food sample.

  8. Radioimmunoassay detection of levels of triiodothyronine and thyroxine in Mangalarga Marchador equine

    International Nuclear Information System (INIS)

    Viana, F.A.B.; Pessoa, J.M.; Biondini, J.

    1991-01-01

    Serum levels of triiodothyronine (T 3 ) and thyroxine (T 4 ) were determined in equine of Mangalarga Marchador breed through radioimmunoassay. Forty-two animals (17 males and 25 females), with age ranging from two to eighteen years, were utilized. The values recorded for males and females were, respectively: 101.68 ± 23.44 and 71.14 ± 18.82 ng/d l of T 3 (P 4 (P<0.05). (author). 10 refs, 1 tab

  9. Clarification of the technic of intrinsic factor radioimmunoassay for the cat and the rat

    International Nuclear Information System (INIS)

    Perrin, M.O.; Nicolas, J.P.; Dubrasquet, M.

    1983-01-01

    Cats and rats secrete very small quantities of gastric juice (GJ). In order to measure the Intrinsic Factor (IF) in GJ of animals certain modifications are necessary. It is very important to select with great care pernicious anemia sera which will be used to cross react with the animals' IF to determine their IF level by radioimmunoassay. The technic described here enables the dosage of low quantities of IF with a 7 per cent coefficient of variation [fr

  10. Radioimmunoassay of haloperidol in human serum: correlation of serum haloperidol with serum prolactin

    International Nuclear Information System (INIS)

    Poland, R.E.; Rubin, R.T.

    1981-01-01

    A radioimmunoassay (RIA) for measurement of serum haloperidol is described. Compared to gaschromatography (GC), RIA vaues average 40% higher. However, a simple organic extraction of serum yields statistically equivalent RIA and GC haloperidol determinations. For both men and women combined, there was a positive correlation between dose (mg/kg/day) and steady-state serum haloperidol level (r = +0.86) and between steady-state serum haloperidol and serum prolactin (PRL) concentration

  11. Steroid radioimmunoassay: contribution of standards to blank values, ch. 4

    International Nuclear Information System (INIS)

    Froelich, M.; Termorshuizen, W.; Kenter, E.; Molenaar, A.J.

    1977-01-01

    The sensitivity of the radioimmunoassay of steroids is considerably reduced by high blank values which may be derived in part from co-chromatographed standards. Blank levels approach the detection limit of the radioimmunoassay of aldosterone, testosterone and androstenedione when 10,000 dpm (30-35 pg) labelled steroids are used as reference standard. When 20 μg aldosterone, testosterone, or androstenedione is used as standard, blank levels of up to 12,800 pg were measured in the radioimmunoassay. Application of the standards on a separate strip does not improve the results. From the experiments it appeared that contamination took place by transport by the solvent

  12. Immature transformed rat islet beta-cells differentially express C-peptides derived from the genes coding for insulin I and II as well as a transfected human insulin gene

    DEFF Research Database (Denmark)

    Blume, N; Petersen, J S; Andersen, L C

    1992-01-01

    is induced in the transformed heterogeneous rat islet cell clone, NHI-6F, by transient in vivo passage. During this process a transfected human insulin gene is coactivated with the endogenous nonallelic rat insulin I and II genes. Newly established cultures from NHI-6F insulinomas having a high frequency...... of insulin-producing cells showed highly differential expression at the cellular level of the three proinsulin C-peptide immunoreactivities, as follows: C-peptide I greater than human C-peptide greater than C-peptide II. The fractions of cells expressing human C-peptide and C-peptide II decreased in time...... species of proinsulin-C-peptide immunoreactivity but still at high levels. However, rat C-peptide II and human C-peptide were often colocalized, even in later passages. In situ hybridization studies combined with the immunocytochemical data suggest that the differential expression occurs at the level...

  13. Beta-endorphin radioimmunoassay: specificity studies

    Energy Technology Data Exchange (ETDEWEB)

    Colas-Linhart, N.; Perdrisot, R.; Petiet, A.; Bok, B.

    1986-01-01

    This note describes the technical details of a cerebrospinal fluid (CSF) B-Endorphin (B-End) radioimmunoassay (RIA). We used an antiserum raised in rabbits against human B-End which cross-reacs 100% with B-Lipotrophin (B-Lph). Thus, filtration chromatography is used to separate both peptides. The assay is sensitive (limit detection=14 pmoles/l), reproducible (the intra and inter assay coefficients of variation are 5 and 6% respectively). Specificity studies are performed to verify the cross-reactions with other opioid peptides and the non specific reactions with the biological fluid (CSF). In order to evaluate the effects of iodine-containing contrast media on the RIA, additional standard curves were analyzed in the presence of varying concentrations of two contrast materials.

  14. Radioimmunoassay of cholecystokinin in tissue and plasma

    International Nuclear Information System (INIS)

    Jansen, J.B.M.J.

    1984-01-01

    The physiological and pathophysiological role of the pancreas hormone, the polypeptide 'cholecystokinin' (CCK) is not well-established yet. This is due to the lack of specific and reliable radioimmunoassays for CCK. The aim of this thesis is to develop such an assay meeting the requirements of high specificity and sensitivity. Several problems were faced, such as (1) the cross-reactivity of existing antibodies with the stomach hormone gastrin and (2) changes in immunoreactivity caused by the introduction of the labelling isotope 125 I and various labels (prepared according to the Bolton-Hunter method) into the polypeptide. The reliability of the assay for the measurement in human tissue and blood is extensively evaluated, inter alia, in patients with pancreas insufficiency (alcohol, cystic fibrosis) and with coeliac disease. (Auth.)

  15. Radioimmunoassay in basic and clinical pharmacology

    International Nuclear Information System (INIS)

    Patrono, C.; Peskar, B.A.

    1987-01-01

    The subject of the book is the development, validation and application of radioimmunoassay (RIA) techniques for the measurement of a variety of substances in animal and human body fluids. The book discusses methodological and conceptual issues related to the main classes of mediators of drug action and to drugs themselves, as assayed by this particular analytical technique. A number of introductory chapters provide basic information concerning production and characterization of antibodies, labeling techniques, statistical aspects and validation criteria, insight into problems related to the development and validation of RIA for the newly discovered mediator(s). In the following chapters, the emphasis is placed on the technical details relevant to each class of compounds and on specific aspects of their applications to basic and/or clinical pharmacological studies. New developments in this area, such as monoclonal antibodies and non-radioactive labeling techniques, are also covered

  16. Studies on a radioimmunoassay for human erythopoietin.

    Science.gov (United States)

    Lertora, J J; Dargon, P A; Rege, A B; Fisher, J W

    1975-07-01

    A highly purified erythropoietin (ESF) preparation (12,000 units per milligram of protein) was labeled with Na'125I using the Chloramine-T method. Undamaged immunoreative labeled ESF was separated from the damaged, nonimmunologically receiveESF by Sephadex G-150 fractionation. This undamaged immunreactive ESF was usedin radioimmunoassay for human erythropoietin. Separation of bound from free antigen was acheived using the double-antibody technique. Approximately 55 per cent binding wasobserved at an antiserum dilution of 1:1500. This assay appears to be sensitive enough to detect as little as 0.025 milliunits of the International Reference Preparation erythropoietin. The estimated levels of thid hormone in normal and anemic uremic human subjects suggests that immunoreactive serum erythropoietin levels are elevated above normal in anemia of uremia.

  17. Radioimmunoassay of 17-beta - estradiol in plasma

    International Nuclear Information System (INIS)

    Kyian, T.S.; Wajchenberg, B.L.

    1980-01-01

    A radioimmunoassay technique for the measurement of plasma E 2 was standardized utilizing a highly specific antisera against E 2 [-6(-0-carboximetil)-oxime] BSA without the need of previous chromatographic purification. The anti-E 2 serum was highly specificic, showing high affinity with affinity constants:K 1 =1.62 x 10 12 M -1 and K 2 =2.94x10 11 M -1 , calculated by Scatchard plot. The standard-curve sensitivity was 2 picograms. The method was specific and accurate, showing an intra-assay precision with a mean C.V. of 2.9%, with the inter-assay evaluation showing a mean C.V. of 5.0%. This method was employed to evaluate E 2 secretion during the menstrual cycle in 6 normal female. (Author) [pt

  18. A direct radioimmunoassay for aldosterone in plasma

    International Nuclear Information System (INIS)

    Lun, S.; Espiner, E.A.; Nicholls, M.G.; Yandle, T.G.

    1983-01-01

    This rapid radioimmunoassay for aldosterone is performed directly on 100 microL of unprocessed plasma, with 125 I-labeled aldosterone as the labeled antigen. Researchers use of steroid-free plasma in preparing the standard curve resulted in an overestimate of aldosterone; this problem was overcome by adding to such plasma a mixture of other steroids to provide a constant steroid/aldosterone ratio. Over a wide range of aldosterone concentrations, results agreed well between the present assay and a routine method involving solvent extraction and paper chromatography (r . 0.85), and sensitivity (20 ng/L) and inter- (10.4%) and intra- (3.9%) assay CVs were better with the present assay. This assay is especially useful for multiple samples and (or) when only small-volume samples are available

  19. A beta-endorphin radioimmunoassay: specificity studies

    International Nuclear Information System (INIS)

    Colas-Linhart, N.; Perdrisot, R.; Petiet, A.; Bok, B.

    1986-01-01

    This note describes the technical details of a cerebrospinal fluid (CSF) B-Endorphin (B-End) radioimmunoassay (RIA). We used an antiserum raised in rabbits against human B-End which cross-reacs 100% with B-Lipotrophin (B-Lph). Thus, filtration chromatography is used to separate both peptides. The assay is sensitive (limit detection=14 pmoles/l), reproducible (the intra and inter assay coefficients of variation are 5 and 6% respectively). Specificity studies are performed to verify the cross-reactions with other opioid peptides and the non specific reactions with the biological fluid (CSF). In order to evaluate the effects of iodine-containing contrast media on the RIA, additional standard curves were analyzed in the presence of varying concentrations of two contrast materials [fr

  20. Radioimmunoassay of cholecystokinin in human plasma

    International Nuclear Information System (INIS)

    Byrnes, D.J.; Henderson, L.; Borody, T.; Rehfeld, J.F.

    1981-01-01

    A sensitive radioimmunoassay for cholecystokinin (CCK) has been developed. Porcine CCK-33 was labelled by conjugation with 125 I-hydroxyphenyl-propionic acid succinimide ester. Antibodies were raised against porcine CCK-33 covalently coupled to egg albumin. Plasma samples were extracted with 96% ethanol prior to assay. Free and bound hormone were separated by dextran-coated charcoal. The antibodies bound CCK-8 and CCK-33 with equimolar potency. The assay detection limit was 1 pmol/l plasma. Within and between assay coefficients of variation were +-12.7 and 13.0% at mean plasma CCK concentrations of 13.2 and 13.6 pmol/l. The concentration of CCK in 47 normal fasting subjects ranged from undetectable to 22 pmol/l. Ingestion of a mixed meal in 9 normal subjects increased the plasma concentration from 8.3 +- 2.5 S.E. to 24.4 +- 6.5 pmol/l. (Auth.)

  1. Report on the national seminar on radioimmunoassays

    International Nuclear Information System (INIS)

    1979-01-01

    Deliberations of the National Seminar on Radioimmunoassays (RIA) held at Bombay during 16-20 January 1978 are reported. Various aspects of the application of RIA techniques in India were discussed in the seminar. They included the basic requirements of RIA in India, the state-of-the-art of RIA in India, radiation protection in RIA, quality control of RIA, usefulness and limitations of RIA in clinical diagnosis and use of RIA in tropical infectious diseases. Difficulties encountered in the practice of RIA techniques in India were found to be mainly related to availability of 125 I, RIA kits, antisera and hormones. The need for establishing a centralised assay service for RIA was examined and it was concluded that such a step would be premature in the present situation. Recommendations made and guidelines spelt out deal with resources for RIA, research, referral assay service, training and information exchange and dissemination. (M.G.B.)

  2. Radioimmunoassay for GRF and CRF in humans

    International Nuclear Information System (INIS)

    Stalla, G.K.; Losa, M.; Kaliebe, T.; Stalla, J.; Schopohl, J.; Muller, O.A.; Von Werder, K.

    1987-01-01

    In 1981 the structure of ovine CRF was established. One year later others isolated a 44 amino acid peptide with GH releasing activity from a pancreatic islet cell carcinoma of an acromegalic patient (hp GRF/sup 1-44/). In 1983 the gene of human CRF was cloned and the amino acid sequence of hCRF could be elucidated. It differs in 7 amino acids from oCRF. Many investigators demonstrated the biological activity of these peptides in vitro and in vivo. The aim of the authors study was to establish radioimmunoassays for GRF and hCRF with the synthetic derivates, measure endogenous GFR and CRF and circulating GRF- and CRF-levels after intravenous injection and calculate metabolic clearance rate and half-time of disappearance from serum for both releasing hormones

  3. The application of α1-MG radioimmunoassay in the diagnosis of kidney diseases

    International Nuclear Information System (INIS)

    Liu Guifen; Wang Jianchun; Zhang Qingfeng; Liu Shuying; Han Wensheng; Li Zhihong

    1996-01-01

    A new method for the diagnoses of kidney diseases with α 1 -microglobulin (α 1 -MG) radioimmunoassay is developed. 276 healthy persons' serum and urine are determined by α 1 -MG radioimmunoassay. The result shows that the serum normal number is 54.22 +-22.02 mg/l and the urine 5.57 +- 2.63 mg/l. In contrast, the counterparts of 358 patients with different diseases are also examined. The result shows that there is a remarkable difference between urine α 1 -MG content of patients suffering from such diseases as gestation hypertension, renal insufficiency, nephritis and that of the healthy group (P<0.01). The method provides a stable, sensitive index for the diagnoses of kidney diseases and the examination of kidney function. It can be widely used in the clinical diagnosis

  4. Radioimmunoassay of diagoxin with the aid of the solid phase - microtitre plating technique

    International Nuclear Information System (INIS)

    Scheidt, C.

    1982-01-01

    Preliminary results are reported here on the development of a digoxin-radioimmunoassay with an anti-digoxin antibody (goat) in a solid phase technique (mictrotitre plate). The advantages compared to conventional RIAs are: Cross reactions towards digoxin is minimal, both in vitro and in vivo. The calibraton range extends from 0.25 to 8 ng/ml. The radioactive load could be reduced significantly by use of smaller amounts of tracer (0.004 μCi/single determination) and by reduction of waste volume (solid), waste weight (solid) and liquid waste. The DIGOXIN RIA BIOTEST MTP is, in addition, the only digoxin radioimmunoassay where radioactive waste is produced in a sealed form. The test is a simple one and can be carried out without the need for complicated apparatus and techniques. (orig./MG) [de

  5. Predicting success of metabolic surgery: age, body mass index, C-peptide, and duration score.

    Science.gov (United States)

    Lee, Wei-Jei; Hur, Kyung Yul; Lakadawala, Muffazal; Kasama, Kazunori; Wong, Simon K H; Chen, Shu-Chun; Lee, Yi-Chih; Ser, Kong-Han

    2013-01-01

    Surgery is the most effective treatment of morbid obesity and leads to dramatic improvements in type 2 diabetes mellitus (T2DM). Gastrointestinal metabolic surgery has been proposed as a treatment option for T2DM. However, a grading system to categorize and predict the outcome of metabolic surgery is lacking. The study setting was a tertiary referral hospital (Taoyuan City, Taoyuan County, Taiwan). We first evaluated 63 patients and identified 4 factors that predicted the success of T2DM remission after bariatric surgery in this cohort: body mass index, C-peptide level, T2DM duration, and patient age. We used these variables to construct the Diabetes Surgery Score, a multidimensional 10-point scale along which greater scores indicate a better chance of T2DM remission. We then validated the index in a prospective collected cohort of 176 patients, using remission of T2DM at 1 year after surgery as the outcome variable. A total of 48 T2DM remissions occurred among the 63 patients and 115 remissions (65.3%) in the validation cohort. Patients with T2DM remission after surgery had a greater Diabetes Surgery Score than those without (8 ± 4 versus 4 ± 4, P Surgery Score also had a greater rate of success with T2DM remission (from 33% at score 0 to 100% at score 10); A 1-point increase in the Diabetes Surgery Score translated to an absolute 6.7% in the success rate. The Diabetes Surgery Score is a simple multidimensional grading system that can predict the success of T2DM treatment using bariatric surgery among patients with inadequately controlled T2DM. Copyright © 2013 American Society for Metabolic and Bariatric Surgery. Published by Elsevier Inc. All rights reserved.

  6. Metabolic risk profiles in diabetes stratified according to age at onset, islet autoimmunity and fasting C-peptide

    DEFF Research Database (Denmark)

    Wod, Mette; Yderstræde, Knud B; Halekoh, Ulrich

    2017-01-01

    autoantibodies (GADab) defines groups with differences in glycaemic control and markers of cardiometabolic risk. DESIGN AND METHODS: A cohort of 4,374 adults with relatively newly diagnosed diabetes referred to a Danish hospital during 1997-2012 was stratified according to age at onset above or below 30 years......OBJECTIVE: Islet autoimmunity, age at onset and time to insulin treatment are often used to define subgroups of diabetes. However, the latter criterion is not clinical useful. Here, we examined whether an unbiased stratification of diabetes according to age at onset, fasting C-peptide and GAD......, fasting C-peptide above or below 300 pmol/l (CPEPhigh or CPEPlow), and presence or absence of GADab (GADpos or GADneg). HbA1c, BMI, blood pressure (BP), lipid profile, alanine aminotransferase (ALT) and creatinine were evaluated. RESULTS: GADab were present in 13% of the cohort. Age at onset...

  7. Radioimmunoassay of methaqualone in human urine compared with chromatographic methods

    International Nuclear Information System (INIS)

    Mule, S.J.; Kogan, M.; Jukofsky, D.

    1978-01-01

    The 125 I-radioimmunoassay for methaqualone in human urine was evaluated by a comparison with newly modified gas-liquid chromatographic and thin-layer chromatographic methods. The statistically significant sensitivity value for the radioimmunoassay was at 2 μg of methaqualone per liter of urine. The coefficient of variation was 2.88 -+ 0.16% intraassay. There was cross-reactivity only with metabolites of methaqualone, 4'-hydroxymethaqualone being twice as sensitively measured as methaqualone. There was complete agreement between results by radioimmunoassay and by gas-liquid chromatography in 96.7% of the samples analyzed. Only 1.2% of the radioimmunoassay values were false positives, and 2.1% false negatives (phi = 0.8917, P < 0.001). Comparisons between the thin-layer chromatographic data and the gas--liquid chromatographic or radioimmunoassay data showed less agreement because of the 50- to 200-fold higher sensitivity of the latter techniques. Gas--liquid chromatography therefore appears to represent the best reference method for the evaluation of the radioimmunoassay, which appears to be a very sensitive and reliable technique for detecting methaqualone and its metabolites in human urine

  8. C-Peptide, Baseline and Postprandial Insulin Resistance after a Carbohydrate-Rich Test Meal - Evidence for an Increased Insulin Clearance in PCOS Patients?

    Science.gov (United States)

    Stassek, J; Erdmann, J; Ohnolz, F; Berg, F D; Kiechle, M; Seifert-Klauss, V

    2017-01-01

    Introduction Known characteristics of patients with PCOS include infertility, menstrual disorders, hirsutism and also often insulin resistance. These symptoms increase with increasing body weight. In the LIPCOS study ( L ifestyle I ntervention for Patients with Polycystic Ovary Syndrome [ PCOS ]) long-term changes of the PCOS in dependence on pregnancy and parenthood were systematically assessed. In the framework of the LIPCOS study, PCOS patients were given a standardised carbohydrate-rich test meal in order to examine glucose homeostasis and insulin secretion. The results were compared with those of a eumenorrhoeic control group who all had corresponding BMI values and corresponding ages. Methods and Patients 41 PCOS patients (without diabetes) and 68 controls received a standardised carbohydrate-rich test meal (260 kcal, 62 % carbohydrates, 32 % fat, 6 % proteins) in order to generate a submaximal insulin and glucose stimulation. The values were determined at baseline and postprandial after 60, 120 and 180 minutes. In addition, the corresponding C-peptide levels were recorded. Results In the PCOS patients (n = 41), the insulin secretion test after a standardised test meal showed almost identical baseline and postprandial insulin levels when compared with those of the age- and BMI-matched eumenorrhoeic controls (n = 68). In the PCOS patients, the baseline and postprandial glucose levels were significantly elevated (92.88 ± 10.28 [PCOS] vs. 85.07 ± 9.42 mg/dL [controls]; p PCOS patients formally exhibit a higher fasting insulin resistance than controls. In spite of the higher stimulated C-peptide levels, the insulin levels did not increase more strongly with increasing glucose levels than in controls which may be indicative of a higher insulin clearance in PCOS patients.

  9. Comparison of the methods for tissue triiodothyronine T(3) extraction and subsequent radioimmunoassay

    International Nuclear Information System (INIS)

    Takaishi, M.; Miyachi, Y.; Aoki, M.; Shishiba, Y.; Asahi Life Foundation, Tokyo

    1978-01-01

    Although there have been various reports on tissue T 3 concentration, the examination of the quality of radioimmunoassay has not been available. In the present study, we tried to determine whether the available methods for T 3 extraction are adequate for the various methods of T 3 radioimmunoassays used. T 3 was extracted from liver by ethanol extraction or by acid butanol extraction (Flock's method) and the extract was applied to radioimmunoassay either by Seralute T 3 column, ANS-double antibody or the ANS-charcoal method. The values of T 3 were compared with those obtained by isotope-equilibration method. The dilution curve of ethanol extract was not parallel with that of the standard in ANS-charcoal or ANS-double antibody technique. When the extract was tested by Seralate method, the dilution curve was parallel to the standard, whereas the T 3 value obtained with this method was two-fold higher than that with the isotope equilibration technique. The analysis of the ethanol extract suggested that the lipid extracted by ethanol interfered with the assay. The acid butanol extract when tested either by the ANS-double antibody or Seralate method, showed parallelism to the standard curve and gave T 3 values almost identical with those by the isotope-equilibration method. When tested by ANS-charcoal method, the dilution curve of the acid butanol extract was not parallel to the standard. Thus, to obtain reliable results, tissue extraction by Flock's method and subsequent T 3 radioimmunoassay by either ANS-double antibody or Seralate T 3 method are recommended. (author)

  10. Development of an enzyme-radioimmunoassay for the measurement of dopamine in human plasma and urine

    International Nuclear Information System (INIS)

    Faraj, B.A.; Walker, W.R.; Camp, V.M.; Ali, F.M.; Cobbs, W.B. Jr.

    1978-01-01

    An enzyme-radioimmunoassay for the measurement of dopamine is described. It is based on the incubation of plasma or urine in the presence of catechol-0-methyltransferase and S-adenosylmethionine. The 0-methylated dopamine metabolite formed (3-0-methyldopamine) was characterized by radioimmunoassay. As little as 0.5 ng of dopamine can be detected. The assay was found to be specific, since no cross-reactivity was noted for several compounds related to dopamine. The enzyme-radioimmunoassay of dopamine was used to determine the concentrations of dopamine in urine and plasma of normal volunteers. In this group, urinary dopamine averaged 182.1 +- 2.2 μg/24 hr, and the plasma concentration 0.211 +- 0.052 ng/ml. However, in children wPth neuroblastoma, there was a several-fold increase over controls in the average urinary and plasma levels of dopamine (8,500 μ/24 hr and 2.3 ng/ml). The assay was also used to monitor blood levels of dopamine following the administration of L-dopa and dopamine to patients with cardiomyopathy

  11. Development and clinical application of human gastrin radioimmunoassay

    International Nuclear Information System (INIS)

    Ginabreda, M.G.P.; Borghi, V.C.; Bettarello, A.

    1988-08-01

    The determination of human gastrin levels in the blood is very important for diagnosis of gastrointestinal disorders. This work describes the radioimmunoassay of gastrin developed according to Russell et al. and its clinical application measuring fasting levels of this hormone in normal subjects, gastrectomized, chagasics, patients with chronic renal failure (CRF), pernicious anemia (PA) and Zollinger-Ellison syndrome (ZES). Synthetic human gastrin was used for radioiodination and as standard, while the specific antibody was raised in rabbits. Gastrin was radioiodinated by a modification of the chloramine T technique and purified by anion exchange chromatography in QAE-Sephadex A-25 to a specific activity around 200 uCi/ug. The assays were performed by incubation of 125 I-gastrin, standard gastrin (zero to 500 pmol/l) or unknown samples with the antiserum for 4 days at 4 0 C. The antibody bound and free 125 I-gastrin was separated by adsorption of the latter to the charcoal. The basal gastrin values of normal subjects ranged from 2 to 74 pmol/l, being these levels higher in the chagasics (from 6 to 261 pmol/l). Higher levels of gastrin were determined in patients with CRF (from 12 to 350 pmol/l), PA (from 160 to 680 pmol/l) and with ZES(1010 pmol/l), while very low levels were confirmed in gastrectomized (from 1 to 8 pmol/l). (author) [pt

  12. Radioimmunoassay of antidiuretic hormone. Application to rats and to man

    International Nuclear Information System (INIS)

    Fressinaud-Masdefeix, Philippe.

    1976-06-01

    The general principles of antidiuretic hormone secretion are known from kidney function explorations and the use of biological methods. Radioimmunoassay of the hormone should contribute towards a better understanding of this secretion in the fields of both physiology and pathology. After a review on antidiuretic hormone and the methods used so far for its investigation, part two of this work concentrates on the development of our own radioimmunological system applied to this hormone. The system is specific, though interference in the measurement from metabolite(s) of the hormone cannot be absolutely ruled out; reproducible, as witnessed by the 'inter-test' variation coefficient of 8%; and sensitive, since the hormone is easily measured in the urine, when secretion is slowed down. In spite of its sensitivity however the hormone determination in the plasma is not possible for a small sample volume because of the difficulty of obtaining high-affinity specific antibodies. To our knowledge only one plasma ADH determination is in common use to date. Part three is devoted to the application of this technique in rats and man, and the results obtained [fr

  13. Development of radioimmunoassay for prolactin binding protein

    International Nuclear Information System (INIS)

    Raikar, R.S.; Sheth, A.R.

    1982-01-01

    Using a homogenous prolactin binding protein (PBP) preparations from rat seminal vesicle secretion, a sensitive and specific radioimmunoassay (RIA) for PBP has been developed. The assay was highly specific and showed no cross-reaction with other protein hormones from various species. The antiserum had an affinity constant (Ka) of 2.66 x 10 10 M -1 . The assay sensitivity was in the range of 0.5-1.0 ng of pure PBP per assay tube and the intra- and inter-assay coefficients of variations were 6-8% and 12-14.5% respectively. The overall recovery of PBP to the rat seminal vesicle secretion was 96.8%. Using this RIA, PBP levels in various biological fluids and reproductive tissues were measured. Azoospermic human semen contained significantly higher levels of PBP than normospermic semen. The seminal vesicle of rat exhibited the highest concentration of PBP. Administration of antiserum to PBP to mature male rats resulted in a significant reduction in the weight of ventral prostrate and serum prolactin levels were significantly elevated in these animals suggesting that the antibody raised against the PBP was capable of blocking prolactin receptors. (author)

  14. Chemical Kinetics of Progesterone Radioimmunoassay System

    International Nuclear Information System (INIS)

    Abdel-Fattah, A.A.; Moustsfs, K.A.; El-Kolally, M.T.

    2004-01-01

    Progesterone is one of the steroids secreted by the corpus Iuteum in females during the menstrual cycle, and in a much higher amount by the placenta during pregnancy. It is also secreted in a minor quantities by the adrenal cortex in both males and females. Measurement of serum progesterone represents one of diagnostic values in menstrual disorders and infertility. The progesterone radioimmunoassay is based on the competition between unlabelled progesterone and a fixed quantity of 125 I-labeled progesterone for a limited number of binding sites on progesterone specific antibody. Allowing for a fixed amount of magnetizable immunosorbent to react, the antigen-antibody complex is bound on solid particles which are then separated by magnetic rack, and the radioactivity of the solid phase was counted using gamma counter. In this work, the chemical kinetics of the assay was followed, where the specific rate constant (K) was calculated at 4 degree and 37 degree and the activation energy (E act ) were calculated and the reaction rate was deduced

  15. The radioimmunoassay of human serum inhibin

    International Nuclear Information System (INIS)

    McLachlan, R.; Robertson, D.M.; Healy, D.L.; Findlay, J.K.; De Kretser, D.M.; Burger, H.G.

    1987-01-01

    The measurement of circulating inhibin is essential to the advancement of our understanding of its role in the control of FSH secretion. Recently, sensitive in vitro bioassay systems have been described which have allowed the measurement of inhibin bioactivity in the peripheral serum of immature female rats, sheep and women (C. Tsonis, personal communication) following ovarian hyperstimulation with exogenous gonadotrophins. Inhibin bioactivity has also been shown to rise in ovarian venous blood in the late follicular phase of women and during FSHG administration to primates. Such studies have some important limitations, in particular, the bioassay systems employed lack the sensitivity required for the study of normal physiology, and questions regarding the specificity of in vitro bioassay in application to serum samples have arisen following the reports of FSH releasing factors (transforming growth factor-beta inhibin B subunit dimers) that may confound the accurate assessment of inhibin bioactivity. This paper reports on the development of sensitive and specific radioimmunoassay (RIA) systems applicable to human serum utilizing highly purified preparations of 58kDa and 31kDa bovine follicular fluid (bFF) inhibin. The development of two RIA systems utilizing antisera raised to either or 31kDa bFF inhibin is detailed and their application to the study of inhibin physiology in the human female during ovulation inducting, the normal menstrual cycle and gestation described

  16. Radioimmunoassay in developing countries: General principles

    International Nuclear Information System (INIS)

    Piyasena, R.D.

    1992-01-01

    Radioimmunoassay (RIA) is probably the most commonly performed nuclear medicine technique. It is an in vitro procedure, where no radioactivity is administered to the patient. But this alone is not the reason for its widespread use. It provides the basis for extremely sensitive and specific diagnostic tests, and its use in present day medicine has brought a virtual information explosion in terms of understanding the pathophysiology of many diseases. The fact that the technology involved is within the technical and economic capabilities of the developing world is evident from the increasing demand for its introduction or expansion of existing services. RIA facilities need not be restricted to urban hospitals, as in the case of in vivo nuclear medicine techniques, but may be extended to smaller district hospitals and other laboratories in peripheral areas. It is also possible to send blood samples to a central laboratory so that a single centre can serve a wide geographical area. There are many laboratories in the industrialized world that receive a major proportion of samples for assay by mail. In recent years, substantial RIA services have been established in many of the developing countries in Asia and Latin America. The International Atomic Energy Agency (IAEA) and World Health Organisation (WHO) have made vital contributions to these activities and have played a catalytic role in assisting member states to achieve realistic goals. In the past five years, more than 250 individual RIA laboratories in developing member states have been beneficiaries of IAEA projects

  17. Radioimmunoassay for human health in developing countries

    International Nuclear Information System (INIS)

    Piyasena, R.D.; Airey, P.L.; Ganatra, R.D.; Nofal, M.

    1989-01-01

    Since first introduced in the early 1960s, radioimmunoassay (RIA) has gained wide acceptance as an analytical method adopted by an increasing number of developing countries as an appropriate technology that can be managed within the capabilities of local infrastructures. An informed estimate would be that there are, at present, more than 500 hospitals, university, or other laboratories in the developing world engaged in RIA on some scale. In the developing world, RIA is used primarily for patient management, but research activity is also increasing as expertise and resources improve. The majority of patient samples processed are in relation to thyroid disorders. However, the technique also is used widely in the investigation of other endocrine conditions and public health problems. Some developing countries have gained the capability to perform radioisotopic microassays in areas of clinical and research importance such as steroid receptor quantification in breast tissue; diagnosis of bacterial and parasitic disorders; investigation of infertility and sterility; narcotic drug abuse; and organ transplantation. 1 fig

  18. Parathyroid hormone: radioimmunoassay and clinical interpretation

    International Nuclear Information System (INIS)

    Hawker, C.D.

    1975-01-01

    A radioimmunoassay for serum immunoreactive parathyroid hormone (iPTH), which has had widespread clinical use for five years, is described in detail. The iPTH results in large groups of patients are reported, and are discussed in relation to the specificity of the assay and in relation to other assays. The assay has excellent precision and is highly proficient in discrimination of groups of patients. Ninety-three percent of 412 patients with surgically proven primary hyperparathyroidism were confidently separated from normal subjects or patients with hypercalcemia owing to other causes, while 86 percent of 160 patients with chronic renal failure and secondary hyperparathyroidism had iPTH values more than 2 S.D. above the normal mean. Results in patients with ectopic hyperparathyroidism were lower than in primary hyperparathyroidism although these groups showed considerable overlap. The antiserum used in this assay for iPTH appears to be specific for the carboxy-terminal region of the secreted or intact form of PTH but recognizes predominantly the secreted form rather than carboxy-terminal fragments believed to be in the circulation. It does not recognize amino terminal fragments. The assay is useful in selective venous catheterization for preoperative localization of hyperfunctioning parathyroid tissue

  19. Combined radioimmunoassay of HBs-antigen and anti-HBs using the Biotest combRIA-Au kit

    International Nuclear Information System (INIS)

    Kselikova, M.; Novak, J.; Urbankova, J.

    1979-01-01

    Hepatitis B antigen and antibody were determined simultaneously by radioimmunoassay using the Biotest combRIA-Au kit. The results in determining antigens and antibodies in sera with a known content of these substances by this kit nearly equal those of isolated determinations of antigen by the Abbott AUSRIA II-125 kit, and of antibody by the Abbott AUSAB kit, resp., except for a negligible number of sera with a very low content of either antigen or antibody. (author)

  20. A radioimmunoassay for lignin in plant cell walls

    Energy Technology Data Exchange (ETDEWEB)

    Dawley, R.M.

    1989-01-01

    Lignin detection and determination in herbaceous tissue requires selective, specific assays which are not currently available. A radioimmunoassay (RIA) was developed to study lignin metabolism in these tissues. A {beta}-aryl ether lignin model compound was synthesized, linked to keyhole limpet hemocyanin using a water-soluble carbodiimide, and injected into rabbits. The highest titer of the antiserum obtained was 34 {eta}g/mL of model derivatized BSA. An in vitro system was developed to characterize the RIA. The model compound was linked to amino activated polyacrylamide beads to mimic lignin in the cell walls. {sup 125}I Radiolabelled protein A was used to detect IgG antibody binding. The RIA was shown in the in vitro system to exhibit saturable binding. The amount of antibody bound decreased when the serum was diluted. Immunoelectrophoresis and competitive binding experiments confirmed that both aromatic rings of the lignin model compound had been antigenic. Chlorogenic acid, a phenolic known to be present in plant cells, did not compete for antibody binding. The RIA was used to measure lignin in milled plant samples and barley seedlings. Antiserum binding to wheat cell walls and stressed barley segments was higher than preimmune serum binding. Antibody binding to stressed barley tissue decreased following NaClO{sub 2} delignification. The RIA was found to be less sensitive than expected, so several avenues for improving the method are discussed.

  1. The radioimmunoassay of serum alpha-fetoprotein levels

    International Nuclear Information System (INIS)

    Kim, Y. H.; Choi, K. A.; Ahn, K. S.; Suh, W. H.; Lee, M. J.

    1982-01-01

    Alpha-fetoprotein (AFP) was first described in the human fetus in 1956 and became a marker protein of primary liver cancer in adults. Serum AFP levels were measured by radioimmunoassay in 212 patients with a variety of malignant and nonmalignant diseases to determine the incidence of leveis elevated above 40 ng/ml. The results obtained are as follows: In 44 cases of total 212 patients, abnormal AFP levels above 40 ng/ml in serum were measured; 24 of 31 patients with primary hepatocellular carcinoma and primary hepatocellular carcinoma with liver cirrhosis (77.4%), 7 of 51 patients with only liver cirrhosis (13.7%), 4 of 10 patients with metastatic liver cancer (40.0%), 4 of 15 patients with chronic hepatitis (26.7%), 2 of 23 patients with acute hepatitis (8.7%), and each one patient with 6 pancreatic carcinoma and 9 cholangiocarcinoma had elevated serum AFP levels. One pregnant woman with gestation 35 weeks had elevated level, but within normal limit during pregnancy

  2. Radioimmunoassay in the diagnosis of atypical form of thyrotoxicosis

    Energy Technology Data Exchange (ETDEWEB)

    Livshits, G.Ya.

    1984-11-01

    Fifty-six patients with ''unmotivated'' disorder of the cardiac rhythm were examined. A combined radionuclide study including a study of iodoabsorptive function with a standard technique, thyroid visualization and determination of the thyroxin, triiodothyronine level in the blood serum with the radioimmunoassay using standard diagnostic kits, was conducted, Latent thyroid hyperfunction was revealed in 24 patients (42.8%). Study of iodoabsorptive function revealed pathological changes in 8 patients only, whereas raaioimmunoassay revealed a significant elevation of the peripheral thyroid hormone level as compared to that of the control group in 24 patients. The conclusion is that patients with ''unmotivated'' disorder of the cardiac rhythm often suffer from latent thyrotoxicosis which is the main etiological factor and trigger mechanism of arrhythmias. In such a situation they are the only clinical symptom of thyrotoxicosis that makes it possible to regard this form of disease as monosymptomatic. The early detection of the cause of cardiac rhythm disorder and the prescription of pathogenetic thyrostatic therapy resulted in the return of the cardiac cycle rate to normal in all the patients with sinus tachycardia and prevented relapses of the paroxysmal forms of rhythm disorder.

  3. Multiple steroid radioimmunoassays and automation: versatile techniques for reproductive endocrinology

    International Nuclear Information System (INIS)

    Vihko, R.; Hammond, G.L.; Pakarinen, A.; Viinikka, L.

    1977-01-01

    The combination of the efficient steroid separating properties of a lipophilic Sephadex derivative Lipidex-5000sup(TM), with the use of antibodies with carefully selected specificity allows the quantitative determination of pregnenolone, progesterone, 17α-hydroxyprogesterone, androstenedione, testosterone, 5α-dihydrotestosterone, 5α-androstanedione, androsterone and 5α-androstane-3α, 17β-diol from 1-2 ml samples of blood serum, amniotic fluid or 300-600 mg pieces of prostatic tissue. The adaptation of the pipetting unit and incubator of a discrete clinical chemical analyzer, System Olli 3000, for the automation of the radioimmunoassays has resulted in a greatly increased through-put and decreased experimental error of the procedure. In studies on reproductive endocrinology, the methodology developed has allowed the detection of a sex difference in androgen composition of the amniotic fluid early in pregnancy. Further, it is very likely that the decline in steroid production by the testis seen during the first year of life and then in senescence is affected by basically different mechanisms. There are also important differences in the steroid content of normal, hyperplastic and carcinomatous prostate. (orig.) [de

  4. Radioimmunoassay of erythropoietin: analytical performance and clinical use in hematology.

    Science.gov (United States)

    Schlageter, M H; Toubert, M E; Podgorniak, M P; Najean, Y

    1990-10-01

    We report here the performance of a recently commercialized radioimmunoassay kit for determining erythropoietin (EPO) in serum or plasma. The lower detection limit of the method was 3 U/L. Precision, analyzed by the variation coefficients between different assay runs and in the same experiment, was always less than 10%; accuracy was assessed by recovery and dilution tests. In anemic patients (hematocrit 18-39%), the concentration of EPO was logarithmically related to hematocrit. A relatively large dispersion of the results was noted, as reported by others with various RIAs. Patients with severe renal failure demonstrated a very low EPO value, whatever the degree of their anemia. In some chronic anemias resulting from malignancy, EPO concentrations were also relatively low. In the polycythemia vera group, the EPO mean was below normal for greater than 95% of the patients, whatever their clinical stage (first evaluation, relapse, or remission). In contrast, 91% of the patients with pure erythrocytosis had a normal or increased EPO value, even when the etiology was unknown. Measurement of EPO concentration may be useful for the clinical differentiation of myeloproliferative disorders and, subsequently, for their prognosis and choice of treatment.

  5. Radioimmunoassay in the diagnosis of atypical form of thyrotoxicosis

    International Nuclear Information System (INIS)

    Livshits, G.Ya.

    1984-01-01

    Fifty-six patients with ''unmotivated'' disorder of the cardiac rhythm were examined. A combined radionuclide study including a study of iodoabsorptive function with a standard technique, thyroid visualization and determination of the thyroxin, triiodothyronine level in the blood serum with the radioimmunoassay using standard diagnostic kits, was conducted, Latent thyroid hyperfunction was revealed in 24 patients (42.8%). Study of iodoabsorptive function revealed pathological changes in 8 patients only, whereas raaioimmunoassay revealed a significant elevation of the peripheral thyroid hormone level as compared to that of the control group in 24 patients. The conclusion is that patients with ''unmotivated'' disorder of the cardiac rhythm often suffer from latent thyrotoxicosis which is the main etiological factor and trigger mechanism of arrhythmias. In such a situation they are the only clinical symptom of thyrotoxicosis that makes it possible to regard this form of disease as monosymptomatic. The early detection of the cause of cardiac rhythm disorder and the prescription of pathogenetic thyrostatic therapy resulted in the return of the cardiac cycle rate to normal in all the patients with sinus tachycardia and prevented relapses of the paroxysmal forms of rhythm disorder

  6. The radioimmunoassay of clomipramine (Anafranil-Geigy): a tricyclic antidepressant

    International Nuclear Information System (INIS)

    Read, G.F.; Riad-Fahmy, D.

    1977-01-01

    A radioimmunoassay has been developed for the tricyclic antidepressant, clomipramine (Anafranil-Geigy) which allows accurate determination of plasma levels without a pr-assay purification step. This is achieved by generation of specific antisera using an antigen produced by conjugation of clomipramine to bovine serum albumin via the 10,11 bridge positions. As expected cross reaction of the pharmacologically active major metabolite, desmethylclomipramine was 5% and that of didesmethyclomipramine 1%. Specificity was confirmed by comparing titres achieved in the routine assay with those observed in an assay incorporating a pre-assay thin layer chromatographic purification step. Pharmacokinetic data were in agreement with double radioisotope derivative assays and also with previously reported assays using G.C. or G.C./M.S. techniques. The sensitivity is superior to any previous assay known to us for this class of compound. The specificity and precision, coupled with the high sample turnover (greater than 300 samples/week per technician) make the assay ideal for supervision of patient compliance and routine assay of samples generated in large clinical trials. (orig.) [de

  7. Radioimmunoassay of fibrinopeptide A: Modifications of technique and clinical trials

    International Nuclear Information System (INIS)

    Schmid, M.

    1981-01-01

    In 1971 Nossel and coworkers developed a highly sensitive radioimmunoassay for the determination of plasma concentration of fibrinopeptide A. Our own experience gained using this test is reported here as well as a number of improvements in methodology which have not only led to a shortening of the whole test procedure to one day but also to greater ease of handling. The modifications concern a gel adsorption procedure for the extraction of FPA from defibrinated plasma samples, the double antibody method for separating free and antibody-bound tracer-phase in assay and automatic evaluation of test results with the aid of a suitable computer programme. Considerations concerning the specificity of conclusions drawn from the test, in particular the necessity of keepin gout interfering plasmin-induced fibrinogen break-down products, play an important role in all changes of methodology. An attempt was made to define a normal range for FPA-plasma levels and a mean value of 1.51 ng/ml at a standard deviation of 0.69 ng/ml was obtained from 42 clinically healthy test patients. Pathologically evaluated FPA-levels were regularly found in patients with septic or thrombotic illness. (orig./MG) [de

  8. Development and validation of a new radioimmunoassay for parathyrin (PTH)

    International Nuclear Information System (INIS)

    Kao, P.C.; Jiang, N.S.; Klee, G.G.; Purnell, D.C.

    1982-01-01

    A radioimmunoassay for human parathyrin has been developed and characterized with whole-molecule (residues 1-84) human parathyrin and with the 1-34, 44-68,and 53-84 amino acid residue fragments of it. The antiserum used reacted with the whole molecule and with the 44-68 and 53-84 fragments, but not with the 1-34 fragment. Parathyrin concentrations in the serum of 118 normal subjects and of 112 patients with surgically proved primary hyperparathyroidism were determined with this assay. The mean results were 39 (SD 13) μL-Eq/mL for the normals and 111 (SD 77) μL-Eq/mL for the patients with primary hyperparathyroidism (p < 0.0005). The upper 95% confidence limit of the normal range was 60 μL-Eq/mL. For 54 patients with primary hyperparathyroidism, the preoperative values for serum parathyrin, calcium, and phosphate-but not creatinine-were statistically different from the postoperative values (paired t-test, p <0.0005). Normal subjects showed significant (p <0.0005) differences in serum calcium concentrations but not in parathyrin concentrations, compared with concentrations found in cancer patients and patients who had thiazide induced hypercalcemia. Phosphate concentration in serum, although not a specific indicator of disease, is a valuable clue to the diagnosis of primary hyperparathyroidism

  9. Radioimmunoassay of antidiuretic hormone in human urine. Applications

    International Nuclear Information System (INIS)

    Zebidi, Abdelkrim.

    1977-10-01

    This work is devoted mainly to the development of a radioimmunological system of antidiuretic hormone (ADH) determination in the urine and its physiological and pathological applications. The radioimmunological method thus replaces the biological measurement of antidiuretic hormone in the urine. This new technique was not possible until specific arginine vasopressin antibodies were obtained and a labelled hormone was prepared according to the criteria set for a radioimmunoassay. The labelled hormone is lysine vasopressin (greater stability). Although 125 I-LVP has lost most of its biological activity the molecule keeps all its immunological properties, behaving in the same way as non-iodinated synthetic LVP towards anti-LVP antibodies. Once specific antivasopressin antibodies and immunologically competent labelled hormone were available, conditions were defined for the radioimmunological ADH test in the urine. This technique, relatively easy to use, allows twenty samples to be measured simultaneously. With this sensitive, specific and reproducible method, it is thus possible to estimate the urinary ADH excretion rates from a 20 ml volume of urine after previous extraction on amberlite CG 50. This extraction method is aimed at both concentrating the hormone and eliminating non-specific interferences. The hormone extraction yield is about 92%+-8 [fr

  10. An improved method for estradiol-17B radioimmunoassay

    International Nuclear Information System (INIS)

    El-Banna, I.M.; El-Asrag, H.A.; Gamal, M.H.

    1991-01-01

    This work describes an improved radioimmunoassay (RIA) of serum estradiol-17 B (E) using locally generated immuno-chemicals. Estradiol hemisuccinate (E -3-H S) was prepared and conjugated to bovine serum albumin (BSA). The obtained conjugate; E 3-H S: BSA, hadλ max at 280 mu and the steroid BSA molar ratio was 25:1. The immunogen was injected subcutaneously in New Zealand rabbits and large amount of antiserum was harvested with 1 : 10500 antibody titre. The antibody cross reactions with estrone (E ), estriol (E ) and progesterone (P) were determined. Blood samples were collected from cycling Osemi ewes during follicular phase, pregnant ewes near term and daily from a cycling ewe over two consecutive estrous cycles. Serum samples were analysed for E both directly and after diethyl ether extraction (DE). The higher E values were found in the direct assay for pregnant ewes. The direct serum minnature RIA system, described herein, was found to be specific, sensitive, precise and economic.5 fig. 2 tab

  11. Monoclonal antibodies to human chorionic gonadotropin and their application to two-site sandwich radioimmunoassay

    International Nuclear Information System (INIS)

    Mizuchi, A.; Iio, M.; Miyachi, Y.

    1984-01-01

    Monoclonal antibodies were prepared against human chorionic gonadotropin (HCG). One monoclonal antibody recognized a conformational determinant expressed only on native HCG molecule and another monoclonal antibody had the specificity for the epitopes located on the β-subunit of HCG. Monoclonal antibodies reacting with different antigenic determinants on the HCG molecule were used to develop a simplified 2-site sandwich radioimmunoassay in which one monoclonal antibody was immobilized and another labeled with 125 iodine. This assay was highly specific for HCG and there was no cross-reactivity with α,β-subunit of HCG, luteinizing hormone and follicle stimulating hormone. (Auth.)

  12. Radioimmunoassay of CA 19-9 tumor marker in the diagnosis of thyroid cancer

    International Nuclear Information System (INIS)

    Markov, V.V.; Slavnov, V.N.; Komissarenko, I.V.; Kovpak, N.A.; Kovalenko, A.E.; Guda, B.B.

    1999-01-01

    Applicability of determining carbohydrate antigen CA 19-9 content in blood serum, tissue extracts, and thyroid tumor aspiration biopsy samples to the differential diagnosis of benign and malignant tumors of thyroid is studied. Radioimmunoassay was used for measurements. It is shown that determination of marker CA 19-9 in blood serum is not informationally capable for the differential diagnosis of thyroid tumors. Considerable increase in CA 19-9 concentration was found in tumor aspiration biopsy samples from patients with malignant tumors this fact can be used for preoperative diagnosis of thyroid cancer [ru

  13. The role of insulin C-peptide in the coevolution analyses of the insulin signaling pathway: a hint for its functions.

    Directory of Open Access Journals (Sweden)

    Shuai Wang

    Full Text Available As the linker between the A chain and B chain of proinsulin, C-peptide displays high variability in length and amino acid composition, and has been considered as an inert byproduct of insulin synthesis and processing for many years. Recent studies have suggested that C-peptide can act as a bioactive hormone, exerting various biological effects on the pathophysiology and treatment of diabetes. In this study, we analyzed the coevolution of insulin molecules among vertebrates, aiming at exploring the evolutionary characteristics of insulin molecule, especially the C-peptide. We also calculated the correlations of evolutionary rates between the insulin and the insulin receptor (IR sequences as well as the domain-domain pairs of the ligand and receptor by the mirrortree method. The results revealed distinctive features of C-peptide in insulin intramolecular coevolution and correlated residue substitutions, which partly supported the idea that C-peptide can act as a bioactive hormone, with significant sequence features, as well as a linker assisting the formation of mature insulin during synthesis. Interestingly, the evolution of C-peptide exerted the highest correlation with that of the insulin receptor and its ligand binding domain (LBD, implying a potential relationship with the insulin signaling pathway.

  14. Pengaruh Transplantasi Allograf Pancreatic Stem Cell terhadap Kadar Insulin dan C-Peptide Tikus Putih Penderita Diabetes Melitus Tipe I

    Directory of Open Access Journals (Sweden)

    Boedi Setiawan

    2016-09-01

    Full Text Available Diabetes mellitus is one of the degenerative diseases in which the therapy still remains unresolved and is still a serious threat to the global health, including to the health of Indonesian people. The aim of this study was to describe the level of insulin and C-peptide in diabetes mellitus type I white rats treated with pancreatic stem cell allograft through intrapancreatic laparotomy. This study was conducted at the Institute of Tropical Diseases, Universitas Airlangga, Surabaya in a 6 month period (July–December 2014. Twelve male white rats Rattus novergicus Wistar strain, were randomly divided into two groups. The first group (P0 was injected by alloxan, 150 mg/kg body weight, without stem cell therapy. Another group was injected by alloxan, 150 mg/kg body weight, and was treated with 1x106/kg body weight pancreatic stem cell throughintrapancreatic laparotomy (P1. The experiment was finalized on the 31th day of the experiment. The results showed that the blood glucose levels at the end of experiment were highly significantly different p<0.01 between the treatment group that received stem cell therapy (P1 and P0 positive control, although the average value of blood glucose levels was not as normal as on the first day. C-peptide and insulin levels of P0 and P1 group differed significantly (p<0.01. It can be concluded that stem cell therapy through intrapancreatic laparotomy can reduce blood glucose levels and increase the levels of C-peptide and insulin.

  15. Immunodiagnosis of opportunistic mycoses: detection of fungal antigenemia by radioimmunoassays in systemic candidiasis and aspergillosis

    International Nuclear Information System (INIS)

    Weiner, M.H.

    1980-01-01

    The authors have developed radioimmunoassays to the Candida carbohydrate, mannan, and to an Aspergillus cell wall carbohydrate. They evaluate these radioimmunoassays with sera from rabbit models of disseminated mycoses, and further evaluate the radioimmunoassays for their diagnostic usefulness in a panel of patient sera. (Auth.)

  16. Logistics of national radioimmunoassay services and radioimmunoassay trouble shooting in developing countries

    International Nuclear Information System (INIS)

    Hazra, D.K.; Shukla, A.K.; Arvind, B.; Khandelwal, S.; Singh, R.; Lahiri, V.L.

    1986-01-01

    The logistics of national radioimmunoassay services are analysed in regard to: applications of immunoassays in developing countries; provision of matched reagents; collection, storage and transport of patient samples, particularly from rural areas; development of robust new immunoassay systems, especially those using non-isotopic labels; quality control; and interrelation with international agencies and commercial suppliers. The effect of using different methods and temperatures of sample storage on representative glycoprotein, steroid, thyroid and communicable disease analytes is examined. The need for stratification of assay services (district, state and national/regional levels) for various tests is discussed in relation to their clinical urgency. A trouble shooting guide suited to developing countries has been written. Starting from various symptoms of assay failure, it describes the differential diagnosis of likely causes, lists appropriate tests to confirm the diagnosis and finally suggests remedial action to prevent future similar mishaps or to salvage the assay. (author)

  17. Comparison of double-antibody radioimmunoassay with Farr-technique radioimmunoassay and double-antibody enzyme immunoassay for α-fetoprotein

    International Nuclear Information System (INIS)

    Kirkpatrick, A.; Wepsic, H.T.; Nakamura, R.M.

    1977-01-01

    We describe double-antibody procedures for determining α-fetoprotein in human serum. An equilibrium procedure can be done in 24 h with a sensitivity of at least 4 μg/liter and coefficient of variation of 5.5%. There are no interferences from normal human sera or sera with certain commonly seen chemical abnormalities. We also describe and discuss sequential procedures that range in sensitivity from 250 ng to 1 μg/liter and require 24 to 48 h incubation. The precise (mid-range) portion of the dose/response curve for sequential procedures can be shifted to higher or lower values by an adjustment of the time of preliminary incubation of antibody with unlabeled antigen. With a 37 0 C incubation, a sequential procedure can be completed in 7 h. Sensitivity is 1 μg/liter, and coefficient of variation 8.0%. The relative merits of the above assay procedures are discussed. The double-antibody radioimmunoassay is twice as sensitive as the Farr procedure and it is free of the large and variable nonspecific precipitation that accompanies the precipitation of bound antigen with sodium sulfate solution. Double-antibody radioimmunoassay is superior to enzyme immunoassay in both sensitivity and precision

  18. A radioimmunoassay method for the rapid detection of Candida antibodies is experimental systematic candidiasis

    International Nuclear Information System (INIS)

    Huang, Y.; Berry, W.; Cooper, H.; Zachariah, Y.; Newman, T.

    1979-01-01

    Rabbits were employed as experimental models to evaluate a solid-phase radioimmunoassay (RIA) method for the diagnosis of systematic candidiasis. Ten rabbits were incubated subcutaneously to mimic superficial candidiasis and were found to produce no antibodies to Candida as determined by both immunodiffusion and RIA procedures. However, 94 per cent of 18 rabbits systematically infected by intravenous injection of Candida cells were observed to produce antibody as assessed by the RIA technique. These data encourage further tests with human sera and the continued development of this RIA procedure as a useful tool in the early serodiagnosis of systematic candidiasis. (Auth.)

  19. Specific radioimmunoassay of HCG and its α and β subunits: methods and results

    International Nuclear Information System (INIS)

    Reuter, A.M.; Schoonbrood, J.; Franchimont, P.

    1976-01-01

    To create antisera that are specific for the radioimmunoassay of HCG and its subunits, the antisera are neutralized by incubation with LH or HCG. For each RIA system the inhibition curves of HCG and its subunits LH, FSH, TSH and STH are obtained. The 125 I labelled hormones HCG, α and β subunits and LH were chromatographed over a Sephadex G 100 column. Serum of menopausal and pregnant women were chromatographed in the same way and the fractions subjected to RIA. HCG and its subunits were determined by RIA in the sera of patients with different kinds of cancer

  20. Application of pregnancy specific β1 glycoprotein-radioimmunoassay (SP1-ria) in obstetrics and gynecology

    International Nuclear Information System (INIS)

    Zhang Weiyuan

    1988-01-01

    Serum SP 1 values of 395 patients were determined by radioimmunoassay. It was found that SP 1 was apparently absent from the blood of normal men and nonpregnant women, increased with gestational stage in pregnant women, and was highest in late pregnancy. In high-risk pregnancy, SP 1 was lower than normal pregnamey group (PC0.01) could also be detected in ectopic pregnancy. In patients with benign and malignant hydatidiform mole, and choriocarcinoma, AP 1 level decreased with malignant degree. The authors suggest that measurement of SP 1 levels is a valuable index for monitoring high-risk pregnancy, diagnosing ectopic pregnancy and following-up trophoblastic cell diseases

  1. Radioimmunoassay of pharmacologically active compounds: applications to nicotine and its metabolites

    International Nuclear Information System (INIS)

    Langone, J.J.; Vunakis, H. van

    1979-01-01

    Since nicotine is the major tobacco alkaloid, its role in cardiovascular disease, cancer and other physiological effects of cigarette smoking has been the subject of intensive investigation for many years. As part of this investigation into the biochemical and physiological effects of nicotine, the authors developed sensitive and specific radioimmunoassays for the parent alkaloid, a major metabolite cotinine, and for γ-(3-pyridyl)-γ-oxo-N-methylbutyramide (oxoamide). The oxoamide is a minor metabolite derived from cotinine. The authors describe the development of these RIA's and demonstrate their use in determining levels of these compounds in physiological fluids of smokers and in studying metabolic processes in vitro. (Auth.)

  2. Preparation of quality control samples in radioimmunoassay for thyroid stimulating hormone (TSH)

    International Nuclear Information System (INIS)

    Ali, O.M.

    2006-03-01

    To days, the radioimmunoassay is becomes the best technique to analysis different concentrations of substance, especially in medical and research laboratories. Although the specificity of RIA techniques, the quality controls must takes place to give good results as possible. In this dissertation i prepared quality control samples of thyroid stimulating hormone (TSH), to use it in RIA techniques and to control the reliability results of those laboratories which used these methods. We used China production kits of RIA method to determine the level of hormone (low-normal-high) concentration. Statistical parameters were used to drown the control chart of the mean to these data.(Author)

  3. Computer assessment of the informative value of radioimmunoassays for the diagnosis of stomach cancer

    International Nuclear Information System (INIS)

    Ozherel'ev, A.S.; Tkacheva, G.A.; Glazkova, T.G.

    1987-01-01

    Solution rules in the form of differential-diagnositc tables with coefficients of weight and threshold values of 16 different signs were obtained with the help of a computer EC-assisted algorithm of a generalized picture. These signs included tumor antigens, cyclonucleotides and hormones determined in the blood serum of healthy individuals, stomach cancer patients and patients with diseases of nonmalignant origin by means of radioimmunoassay. These signs being of low informative value by themselves, in a combined use provided an opportunity to differentiate between ''stomach cancer-not cancer'' with a sufficiently high degree of significance

  4. Sample preparation for measuring cow's progesterone in radioimmunoassay technique application

    International Nuclear Information System (INIS)

    Nuning Duria; Budi Santoso; Nuniek Lelananingtiyas; Wiranto Budi Santoso

    2010-01-01

    Sample preparation for measuring cow's progesterone in radioimmunoassay technique application has been done. Preparation includes the preparation of samples of cow's milk samples that has been carried out artificial insemination on day 0, 11 and 21. Then the standard making of progesterone in the form of fresh milk or skim milk (non fat) that has been removed its progesterone and through a series of chemical processes. The last is the preparation work on samples using the RIA kit I 125 . With this milk samples preparation, samples can be counted using RIA counter so that concentration of progesterone hormone can be determined accurately. (author)

  5. Direct radioimmunoassay and immunocytochemical localization of renin in human kidneys

    International Nuclear Information System (INIS)

    Menard, J.; N'Goc, P.W.; Bariety, J.; Guyenne, P.T.; Corvol, P.

    1979-01-01

    Highly specific antibodies to human renin were prepared in rabbits and used for the preparation of a renin-free substrate, the direct radioimmunoassay of renin in plasma and kidneys, and the localization of renin with fluoresceinated antibodies. In a patient with a partially infarcted kidney, plasma renin activity, measured enzymatically by the radioimmunoassay of angiotensin I, was increased, and could be activated by acid. The direct measurement of plasma renin by radioimmunoassay gave identical values before and after acidification. In the ischaemic part of the kidney, renin content was high, both by the enzymatic and the direct method of measurement. It was low in the non-ischaemic part of the kidney. Thus whereas renin has been previously measured as an activity by enzymatic assays, this intra-renal hormone can now be measured as an entity by a specific radioimmunoassay in human plasma and kidney tissue. All afferent and some interlobular arteries of the obsolescent glomeruli were stained with fluoresceinated anti-renin antibodies. In the non-ischaemic area, the juxtaglomerular apparatus did not stain. (author)

  6. Cost/benefit and predictive value of radioimmunoassay

    International Nuclear Information System (INIS)

    Albertini, A.; Ekins, R.P.; Galen, R.S.

    1984-01-01

    The present symposium is organized to discuss the benefits of radioimmunoassay. The discussion includes several aspects: the real diagnostic values of the measurements; the way of organization to maximise the diagnostic reliability and usefulness whilst minimizing the real costs; the prospects existing for the improvement of current methods and, implicitly, of cost/benefit ratios. (Auth.)

  7. A solid-phase-radioimmunoassay for total serum thyroxine

    International Nuclear Information System (INIS)

    Moedder, G.; Sokolowski, G.

    1978-01-01

    A new solid phase radioimmunoassay for total serum thyroxine was evaluated over a longer time under clinical routine conditions and compared with an established test system. The results show up that the T 4 values are precise, reliable and reproducible, the is incomplicate to handle and well suitable for semiautomatic pipetting systems. (orig.) 891 MG [de

  8. Monitoring the reproductive performance in awassi ewes using progesterone radioimmunoassay

    International Nuclear Information System (INIS)

    Zarkawi, M.

    1999-01-01

    Jugular serum progesterone (P-4) concentrations were assessed using radioimmunoassay (RIA) kits for about 1 year in 16 local Awassi ewes aged about 1 year and weighing on average 37.4 ±4.9 (range 29.5-44.0 kg). Average pre-mating live weight of animals was different (P 0.05) between animals in average basal pre-mating P-4 concentration, maximum P-4 concentration during the luteal phase in non-pregnant ewes and in the length of the gestation period average basal pre-mating P-4 concentration was 0.62±0.44 (range 0-1.7 nmol l -1 ). Average maximum P-4 concentration during the luteal phase in non-pregnant ewes was 11.0±3.3 (range 5.8-18 nmol l -1 ). Length of gestation period varied from 149 to 155 days with an average of 152±2.3 days. Maximum P-4 concentration during gestation was different (P -1 ). The accuracy of pregnancy diagnosis at around 21 days pot-mating using RIA was 100%. It was concluded that Awassi sheep in Syria have a long breeding season that could start as early as April and last through September. Therefore, ewes might be included in oestrous synchronisation programmes to give three lambs in 2 years. It was also concluded that P-4 concentration under 3.18 nmol l -1 is indicative of either anoestrous or follicular and early luteal phase of the oestrous cycle in Awassi ewes kept in Syria and that RIA could be used for P-4 determination and successful early diagnosis of pregnancy in Awassi sheep. (author)

  9. Quality control of radioimmunoassay reagents for T4

    International Nuclear Information System (INIS)

    Wayan Radiatning, S.

    1987-01-01

    Quality control of radioimmunoassay reagents for T4. A program of quality control testing has been carried out for 125 I-T4, T4 standards and T4 antisera. 125 I-labelled T4 has been tested for its specific activity, radiochemical purity using a Sephadex G-25 column, immunological activity, based on the immunological reaction between labelled antigen and excess T4 antibody, and non-specific binding. The useful shelf-life of the labelled compound was determined by monitoring the decrease in radiochemical purity and immunological activity, and the increase in non-specific binding. T4 standards were calibrated by means of T4 RIA kit manufactured by DPC (Diagnostic Products Corporation). A test on parallelism was also performed using hyperthyroid sera. T4 antisera were evaluated with respect to titre, avidity and specifity. The test results on 125 I-T4 show a specific activity varying between 1830-2020 uCi/ug, a radiochemical purity above 90%, an immunological more than 80% and a non-specific binding of less than 5%. The standard curve for T4 was found to coincide well with the standard curve of the DPC kit and parallel with the curve for hyperthyroid sera. The titre of T4 antisera obtained was 1:300, the avidity was about 4.8 x 10 7 and the cross-reaction for T3 was 1.6%. It can be concluded from the experimental results, that the 125 I-T4, T4 standards and T4 antisera prepared meet the requirements for the manufacture of T4 kits. (author). 5 refs.; 14 figs

  10. Radioimmunoassay for the determination of low insulin levels

    International Nuclear Information System (INIS)

    Toledo e Souza, I.T. de; Wajchenberg, B.L.; Okada, H.

    1988-08-01

    The assay system was set up in such a way as to increase the sensitivity of the reaction, reducing the tracer concentration from the usual 1.000 cpm/ml to 500 cpm/ml levels of radioactivity (specific activity aproximately 200 mCi/mg) and/or increasing the antiserum dilution by one thirty of the usual values in the assay of the final volume of incubation of 2,5 ml. (author) [pt

  11. Production of anti-IgG antibodies in sheep for using in the radioimmunoassays of LH, FSH and prolactin

    International Nuclear Information System (INIS)

    Caso, R.; Perez, E.; Mosquera, M.; Arranz, C.

    1996-01-01

    In this work described the production of second antibodies in sheep against rabbit IgG for being used in radioimmunoassays for determination LH, FSH and Prolactin. There was made the comparison between the results obtained using the Kits-RIA produced by us and the commercial WHO Kits-RIA, using these antibodies. The results allowed us to use these antibodies for production Kits-RIA of LH, FSH and Prolactin

  12. Urinary C-peptide: a useful tool for evaluating the endogenous insulin reserve in cohort and longitudinal studies of diabetes in childhood.

    Science.gov (United States)

    de Beaufort, C E; den Boer, N C; Bruining, G J; Eilers, G A; van Strik, R; Weterings, T

    1988-09-01

    Increasing research into the remission phase of type I diabetes mellitus stresses the importance of a non-traumatic and reliable method for the evaluation of endogenous insulin production. We compared 24-h urinary C-peptide excretion (UCE) with plasma C-peptide values before and after stimulation with 1 mg glucagon in 24 type I diabetic children. Fasting plasma C-peptide values and stimulated plasma C-peptide values showed a linear correlation with 24 h UCE. Mean plasma C-peptide levels correlated inversely with the exogenous insulin dose. A slightly better correlation was found between the exogenous insulin dose and 24 h UCE. Control data of 24 h UCE were obtained from healthy siblings. A linear correlation with age was found up to 10 years of age above which UCE values seem to reach a plateau. This effect of age, as well as the frequency of sampling was taken into account in the derivation of 95% reference intervals for UCE. The measurement of 24 h UCE appears to be a useful parameter to assess endogenous insulin production in diabetic children, provided that age is taken into account.

  13. Development of a sensitive solid-phase radioimmunoassay for melanin-concentrating hormone

    Energy Technology Data Exchange (ETDEWEB)

    Eberle, A.N.; Baumann, J.B.; Girard, J. (Univ. Children' s Hospital, Basel (Switzerland)); Baker, B.I.; Kishida, M. (Univ. of Bath (England))

    1989-01-01

    A two-step solid-phase radioimmunoassay for melanin-concentrating hormone (MCH) was developed for direct determination of the hormone in plasma samples. To this end, synthetic MCH was coupled to bovine thyreoglobulin and the complex was injected into rabbits. Specific antisera of high titer were obtained which did not crossreact with other hormones. The IgGs were chemically linked to immunobeads, an acrylamide/acrylic acid polymer matrix. In the first step, plasma MCH was immunoextracted by incubation of diluted plasma samples with anti-MCH immunobeads. In the second step, the washed polymer was incubated with radioiodinated MCH tracer for titration of non-occupied sites. This procedure made it possible to determine as little as 4 pg MCH per ml of plasma. Application of the radioimmunoassay to plasma levels of black or white background-adapted trout showed a marked difference in circulating MCH: while trout on a black background contained a mean value of 29 {plus minus} 5.6 pg/ml, animals on a white background had 106 {plus minus} 19 pg/ml.

  14. A new unextracted-sample radioimmunoassay method for hepatic endogenous nuclear L-tri-iodothyronine content

    International Nuclear Information System (INIS)

    Yagura, T.; Walfish, P.G.

    1982-01-01

    Endogenous L-tri-iodothyronine content in an hepatic nuclear extract was measured by a new unextracted-sample radioimmunoassay method using 8-anilinonaphthalene-1-sulphonic acid to inhibit the L-[ 125 I]tri-iodothyronine binding to the nuclear L-tri-iodothyronine receptor within the extract. The amount of endogenous L-tri-iodothyronine was 10-40 pg/0.2 ml of hepatic nuclear extract from euthyroid rats, compared with less than 3.125 pg/0.2ml from thyroidectomized rats. The results obtained were compared with a Sephadex G-25 column extracted-sample radioimmunoassay method and showed a good agreement. The values for the endogenous L-tri-iodothyronine content were utilized to correct for the L-tri-iodothyronine concentration within the binding assay mixture in order to accurately determine by Scatchard analysis the binding characteristics of the nuclear L-tri-iodothyronine receptor. The validity of the correction for endogenous L-tri-iodothyronine was demonstrated by using a nuclear extract from a thyroidectomized rat which was preincubated with a small known amount of L-tri-iodothyronine before determining the nuclear L-tri-iodothyronine receptor binding characteristics. It is concluded that the necessity and validity of using endogenous L-tri-iodothyronine corrections in the Scatchard analytical computations of the nuclear L-tri-iodothyronine receptor binding characteristics has been demonstrated, being particularly more important for affinity constant than maximum binding capacity. (author)

  15. Meta-genome-wide association studies identify a locus on chromosome 1 and multiple variants in the MHC region for serum C-peptide in type 1 diabetes.

    Science.gov (United States)

    Roshandel, Delnaz; Gubitosi-Klug, Rose; Bull, Shelley B; Canty, Angelo J; Pezzolesi, Marcus G; King, George L; Keenan, Hillary A; Snell-Bergeon, Janet K; Maahs, David M; Klein, Ronald; Klein, Barbara E K; Orchard, Trevor J; Costacou, Tina; Weedon, Michael N; Oram, Richard A; Paterson, Andrew D

    2018-05-01

    The aim of this study was to identify genetic variants associated with beta cell function in type 1 diabetes, as measured by serum C-peptide levels, through meta-genome-wide association studies (meta-GWAS). We performed a meta-GWAS to combine the results from five studies in type 1 diabetes with cross-sectionally measured stimulated, fasting or random C-peptide levels, including 3479 European participants. The p values across studies were combined, taking into account sample size and direction of effect. We also performed separate meta-GWAS for stimulated (n = 1303), fasting (n = 2019) and random (n = 1497) C-peptide levels. In the meta-GWAS for stimulated/fasting/random C-peptide levels, a SNP on chromosome 1, rs559047 (Chr1:238753916, T>A, minor allele frequency [MAF] 0.24-0.26), was associated with C-peptide (p = 4.13 × 10 -8 ), meeting the genome-wide significance threshold (p C>T, MAF 0.07-0.10, p = 8.43 × 10 -8 ). In the stimulated C-peptide meta-GWAS, rs61211515 (Chr6:30100975, T/-, MAF 0.17-0.19) in the MHC region was associated with stimulated C-peptide (β [SE] = - 0.39 [0.07], p = 9.72 × 10 -8 ). rs61211515 was also associated with the rate of stimulated C-peptide decline over time in a subset of individuals (n = 258) with annual repeated measures for up to 6 years (p = 0.02). In the meta-GWAS of random C-peptide, another MHC region, SNP rs3135002 (Chr6:32668439, C>A, MAF 0.02-0.06), was associated with C-peptide (p = 3.49 × 10 -8 ). Conditional analyses suggested that the three identified variants in the MHC region were independent of each other. rs9260151 and rs3135002 have been associated with type 1 diabetes, whereas rs559047 and rs61211515 have not been associated with a risk of developing type 1 diabetes. We identified a locus on chromosome 1 and multiple variants in the MHC region, at least some of which were distinct from type 1 diabetes risk loci, that were associated with C-peptide

  16. β2-microglobulin, albumin radioimmunoassay and its clinical appraisal

    International Nuclear Information System (INIS)

    Yu Yuming; Zhu Qiyuan; Cheng Guangliang

    1994-01-01

    The β 2 -MG, Alb RIA kits were made in the Radioisotope Department of China Institute of Atomic Energy. They may be used as new type kits inspecting the function indexes of kidney. In the report, these kits are considered to be of high quality by the data of 15 tests. The serum and urine β 2 -MG and urine Alb values of 82 normal subjects and 210 abnormal subjects of different kidney diseases are measured by radioimmunoassay. The results show that the values of β 2 -MG and Alb values of the patients are significantly higher than that of healthy subjects. It is suggested that the β 2 -MG and Alb values measured by radioimmunoassay are very useful and sensitive function indexes of kidney in the clinical diagnosis of different kidney diseases

  17. Radioimmunoassay for nortriptyline (and other tricyclic antidepressants) in plasma

    International Nuclear Information System (INIS)

    Maguire, K.P.; Burrows, G.D.; Norman, T.R.; Scoggins, B.A.

    1978-01-01

    The radioimmunoassay for nortriptyline described here can detect as little 1 μg/liter of plasma. Within-day precision and day-to-day precision (CV) were +-6 and +-11%, respectively, over the concentration range 100 to 200 μg/liter. The major metabolite hydroxy-nortriptyline does not cross react with the antiserum. Results so obtained correlate closely with results by a double-isotope derivative dilution technique. The major advantages of this technique over currently available methods are its sensitivity, convenience (many samples can be processed in one day), simplicity, and cost. Further, prior extraction of plasma samples is not required. Cross-reactivity studies have been carried out with all other available tricyclic antidepressants. The antiserum has the ability to bind these drugs, thus radioimmunoassay for all the tricyclic antidepressant drugs can be set up because concurrent use of more than one of these drugs is rare

  18. Production and use of thyroxine antisera in radioimmunoassay technique

    International Nuclear Information System (INIS)

    Abbas, Sumaia Hussein

    2000-06-01

    This study describes the production of antisera from sheep and its use in the determination of thyroxine hormone (T 4 ) level in serum using radioimmunoassay (RIA) technique. In this study two local sheep (Ovis aris) were subjected to immunization against human T 4 immunogen, sera obtained from both sheep after each injection were subjected to evaluation through titration in a purified and non purified form. The produced antibodies were used to assemble a kit for the determination of total human serum thyroxine. Different separation techniques were tried, (second antibody polyethylene glycol (PEG) assisted precipitation, polystyrene beads and magnetisable particles solid phases). For the PEG assisted precipitation, local antiserum and that produced by the North East Thamus Region Immunoassay (NETRIA donkey anti-sheep serum (DASS) as second antibodies) were tried. The final dilutions of the anti-T 4 antibody used were 1/4000 in a liquid phase using second antibody PEG assisted separation, 1/3000 using magnetizable particles and a dilution of 1/10,000 using polystyrene beads solid phase for separation. Optimization of T 4 assay conditions including incubation temperature and reaction time were done. Tests for T 4 assay validation (linearity, recovery and responsibility) were carried out. For linearity and recovery tests, the regression coefficient ranges were found to be from (0.8 to 0.9) and (0.88 to 0.98) respectively. The assay was found to be reproducible where the coefficients of variation within and between assays were less than 10%. The locally developed assay was found to be comparable with NETRIA assay as a reference method with a correlation coefficient of 0.88, 0.93 and 0.87 for PEG assisted separation, magnetizable particles and polystyrene beads techniques respectively. The clinical validation tests showed a reliable sensitivity, specificity and efficiency with values of 97%, 94% and 96% respectively. When the T 4 concentrations measured using the

  19. Radioimmunoassay of alpha-foeto-protein in hepatology. Observation of 151 cases

    International Nuclear Information System (INIS)

    Dao, Mouhamadou.

    1976-03-01

    Alpha-foeto-protein, although discovered several years ago, was considered as only able to exist in primary adult liver cancer. With progress in science and in research it was observed that AFP can be found in normal subjects, without any pathological significance. APF has been found moreover in illnesses other than primary liver cancer. This range of diseases, restricted at first, has continued to widen, a development due to the discovery of new AFP detection methods and radioimmunoassay. Our work, covering 151 cases discussed in detail in the 'Material and Methods' chapter, is interesting from two viewpoints: in hepatology it is useful to know whether the very sensitive radio-immunological method reveals abnormal AFP content variations in different liver diseases; given the large number of hepatomas in our series it is also interesting to have the value of this determination confirmed in primary liver cancer diagnosis. Radioimmunoassay now replaces other quantitative methods (MANCINI's radial immunodiffusion and LAURELL's elec. diffusion) and is the most accurate [fr

  20. Radioimmunoassay of insulin by the double antibody method. Evaluation of the technique in practice

    International Nuclear Information System (INIS)

    Wojckikowski, C.; Zakoslki, W.

    1974-01-01

    The aim of this study was to develop a simplified procedure for the radioimmunoassay of insulin by the double antibody method. Anti-insulin serum was obtained by immunizing guinea pigs with porcine insulin suspended in Freund's incomplete adjuvant supplemented with Hemophilus pertussis vaccine. After two injections, sera from four guinea pigs diluted 1:10,000 bound more than 70% of the 125 I-insulin added. Under the conditions of the method, the insulin binding reagent bound 43%+-5% (n=94) of added 125 I-insulin. Accuracy of the method in simultaneous series for insulin concentrations of 27 μU/ml and 49 μU/ml was +-5% and +-7% respectively; and in a nonsimultaneous series of determinations for insulin concentrations of 21 μU/ml and 77 μU/ml, +-11% and +-8%. Recovery of insulin added to human plasma was 104%. Concentrations of insulin in the plasma of healthy fasting subjects ranged from 5-22 μU/ml (m=13+-5 μU/ml; n=21). The results were in complete agreement with results obtained by the use of the Amersham radioimmunoassay insulin kit. (author)

  1. A specific radio-immunoassay for Gonadotrophin-releasing hormone

    International Nuclear Information System (INIS)

    Hendricks, S.; Millar, R.; Pimstone, B.

    1975-01-01

    A specific antiserum has been made to synthetic gonadotrophin-releasing hormone (GnRH) conjugated to keyhole limpet haemocyanin and appears to be directed against amino acids 6 - 8 of this decapeptide. This has allowed the development of a radio-immunoassay for GnRH sensitive to 5 picograms per tube. Although it is easily measurable in hypothalamic extracts, we have failed to detect GnRH in plasma and urine from normal subjects and menopausal women

  2. A micro-radioimmunoassay for measurement of rat luteinizing ...

    African Journals Online (AJOL)

    A sensitive and reproducible double antibody radio-immunoassay for rat LH measurement, which requires at most 50μl of serum or plasma per tube, is described for use with 125l and rabbit anti-rat LH serum. The assay has a scnsitivity of 16 ng LH/ml, and coefficients of inter-assay and intra-assay variations of +/-6,6% and ...

  3. Semiautomated radioimmunoassay for mass screening of drugs of abuse

    International Nuclear Information System (INIS)

    Sulkowski, T.S.; Lathrop, G.D.; Merritt, J.H.; Landez, J.H.; Noe, E.R.

    1975-01-01

    A rapid, semiautomated radioimmunoassay system for detection of morphine, barbiturates, and amphetamines is described. The assays are applicable to large drug abuse screening programs. The heart of the system is the automatic pipetting station which can accomplish 600 pipetting operations per hour. The method uses 15 to 30 μl for the amphetamine and combined morphine/barbiturate assays. A number of other drugs were tested for interference with the assays and the results are discussed

  4. Synthesis of iodobuprenorphine for use in radioimmunoassay. [Analgesic

    Energy Technology Data Exchange (ETDEWEB)

    Debrabandere, L.; Boven, M. van; Daenens, P. (Leuven Univ. (Belgium). Lab. of Toxicology)

    1992-08-01

    The synthesis of [[sup 125]I]iodobuprenorphine is described. This compound has been used as a tracer molecule in the development of a new radioimmunoassay for buprenorphine. The parameters that effect the direct iodination of buprenorphine using sodium [[sup 127]I]iodide, in the presence of either chloramine-T or Iodo-Beads, were studied. The structure of iodobuprenorphine was confirmed by mass spectrometry. (author).

  5. Preparation and characterization of reagents for epitestosterone radioimmunoassay

    International Nuclear Information System (INIS)

    Bilek, R.; Hampl, R.; Starka, L.; Putz, Z.

    1987-01-01

    The preparation of reagents, suitable for radioimmunoassay of 17α-hydroxy-4-androsten-3-one (epitestosterone) in body fluids is described. It includes a simplified synthesis of the immunogen, epitestosterone-3-(0-carboxymethyl)oxime coupled to bovine serumalbumin its characterization and preparation of the radioligand ( 125 I) iodohistaminyl derivative of epitestosterone. The assay protocol for epitestosterone detection in urine avoiding extraction is described and the reliability criteria of the method are given. (author)

  6. Proinsulin C-peptide potentiates the inhibitory action of insulin on glucose synthesis in primary cultured rabbit kidney-cortex tubules: metabolic studies.

    Science.gov (United States)

    Usarek, Michal; Jagielski, Adam Konrad; Krempa, Paulina; Dylewska, Anna; Kiersztan, Anna; Drozak, Jakub; Girstun, Agnieszka; Derlacz, Rafal Andrzej; Bryla, Jadwiga

    2014-02-01

    Effects of equimolar concentrations of proinsulin C-peptide and insulin on glucose synthesis were studied in primary cultures of rabbit kidney-cortex tubules grown in the presence of alanine, glycerol, and octanoate. The rhodamine-labeled C-peptide entered renal tubular cells and localized in nuclei, both in the presence and absence of insulin; preincubations with the unlabeled compound inhibited internalization. C-peptide did not affect glucose formation when added alone but potentiated the inhibitory action of insulin by about 20% due to a decrease in flux through glucose-6-phosphate isomerase (GPI) and (or) glucose-6-phosphatase (G6Pase). GPI inhibition was caused by: (i) increased intracellular contents of fructose-1,6-bisphosphate and fructose-1-phosphate, inhibitors of the enzyme and (ii) reduced level of the phosphorylated GPI, which exhibits higher enzymatic activity in the presence of casein kinase 2. A decrease in flux through G6Pase, due to diminished import of G6P by G6P-transporter from the cytoplasm into endoplasmic reticulum lumen, is also suggested. The data show for the first time that in the presence of insulin and C-peptide, both GPI and G6P-ase may act as regulatory enzymes of renal gluconeogenic pathway.

  7. Preoperative Fasting Plasma C-Peptide Levels as Predictors of Remission of Type 2 Diabetes Mellitus after Bariatric Surgery: A Systematic Review and Meta-Analysis.

    Science.gov (United States)

    Yan, Wenmao; Bai, Rixing; Yan, Ming; Song, Maomin

    2017-12-01

    The study evaluated the predictive role of preoperative fasting C-peptide, hemoglobin (Hb)A1c, fasting plasma glucose (FPG), and body mass index (BMI) levels on diabetes remission in patients with type 2 diabetes following bariatric surgery. Medline, PubMed, Central, and Google Scholar databases of up to September 7, 2016 were searched using the following terms: type 2 diabetes mellitus, gastric bypass, Roux-en-Y, anastomosis, C-peptide, weight loss, HbA/HbA1c, predictive/predictor. Meta-analysis of the pooled data indicated that fasting C-peptide was predictive of increased chance of remission of type 2 diabetes (pooled difference in means = 0.93, 95% confidence interval [CI] = 0.61 to 1.25, p fasting plasma C-peptide was associated with increased type 2 diabetes remission after bariatric surgery, whereas baseline HbA1c and FPG levels were associated with reduced chance of remission. These parameters may be used as a guideline in weighing the risks and benefits for surgical intervention in patients with type 2 diabetes.

  8. Placental ghrelin and leptin expression and cord blood ghrelin, adiponectin, leptin, and C-peptide levels in severe maternal obesity.

    Science.gov (United States)

    Allbrand, Marianne; Åman, Jan; Lodefalk, Maria

    2017-08-08

    The purpose of this study is to investigate placental ghrelin and leptin expression as well as cord blood ghrelin and adiponectin levels in maternal obesity and associations between placental ghrelin expression, cord blood ghrelin levels and maternal and infant variables. Placental ghrelin and leptin expression were analyzed by RT-PCR in 32 severely obese and 32 matched normal-weight women. Cord blood ghrelin, adiponectin, leptin, and C-peptide concentrations were analyzed by ELISA. Neither ghrelin nor leptin expression and neither cord blood ghrelin nor adiponectin levels differed between the groups. Placental ghrelin expression was associated with BMI at delivery in the obese women (r = 0.424, p = .016) and in the infants born to normal-weight women with their weight z-scores at six (r = -0.642, p = .010), nine (r = -0.441, p = .015), and 12 months of age (r = -0.402, p = .028). Placental ghrelin and leptin expression as well as cord blood ghrelin and adiponectin levels do not seem to be altered in severe maternal obesity. Placenta-derived ghrelin may influence the infants' postnatal weight gain, but possibly only when the mother has normal weight.

  9. A highly sensitive radioimmunoassay technique for subtyping the antibody to hepatitis B surface antigen

    International Nuclear Information System (INIS)

    Fang, C.T.; Nath, N.; Berberian, H.; Dodd, R.Y.

    1978-01-01

    A highly sensitive technique for determining the subtype specificity of antibody to hepatitis B surface antigen (anti-HBs) is described. Immunoadsorbent consisting of controlled pore glass coated with subtype specific HBsAg was used to remove homologous antibody from the test samples before testing them for residual antibody by a commercially available radioimmunoassay (RIA). A total of 73 anti-HBs-positive samples from asymptomatic blood donors were tested. In nearly 80% of these samples the subtype reactivity could be determined by this technique. Only 67% could be typed by conventional liquid phase absorption RIA and 22% by passive hemagglutination inhibition techniques. Among the samples with low anti-HBs titer, ad and ay subtypes were found with equal frequency; however, with the increase in anti-HBs titer, considerably higher proportion of ad specificity was detected. (Auth.)

  10. A sensitive and specific radioimmunoassay for 1-β-d arabino furanosylcytosine

    International Nuclear Information System (INIS)

    Shimada, Noriaki; Ueda, Takao; Yokoshima, Tetsuyoshi; Oh-ishi, Jun-inchi; Oh-oka, Tadaaki

    1984-01-01

    In order to determine the blood level of 1-β-D-arabinofuranosylcytosine (Ara-C), an antileukemic agent, a sensitive and specific radioimmunoassay (RIA) system using anti-Ara-C serum, (5- 3 H) Ara-C and a dextran-coated charcoal method has been developed. The anti-Ara-C serum obtained from a guinea pig was hardly cross-reactive with 1-β-D-arabinofuranosyluracil (Ara-U), tetrahydrouridine (THU) and other Ara-C analogues. The RIA system for Ara-C could detect concentrations as low as 60 pg/ml in plasma. Average of the intra- and inter-assay variancies at 5, 10, 20 ng/ml were 4.3% and 5.6% respectively. Ara-C in blood samples obtained from human patients who orally received N 4 -palmitoyl-1-β-D-arabinofuranosyl-cytosine (PL-AC) was determined by the present RIA system. (author)

  11. Clinical value of bile acids radioimmunoassay

    International Nuclear Information System (INIS)

    Breckwoldt, R.U.

    1981-01-01

    In 50 blood donors, 87 patients with various liver and bile disorders, 50 hemodialyse patients and 50 patients prior to and immediately after cardiac swigery, cholyl glycine (CG) and sulfolithocholyl glycine (SLCG) were determined. Long-term observations were carried out on a further 10 patients with non-A/non-B hepatitis and 10 patients without hepatitis. Correlations were found between the values of alkaline phosphatase, GPT, GOT and bilirubin. Consequently the determination of bile acid, here above all SLCG, constitutes a suitable means to detect subclinical functional liver disorders. The examination of the post-operative functional liver disorders following cardiac swigery showed that there is a distinct time shift between the mostly transitory increase in enzyme activity and the SLCG levels. Surprisingly, the long-term observations showed that increased bile acid levels are already measured during the hepatitis incubation period at normal enzyme activities. It was not possible, however to identify hepatitic patients already during incubation by assay of the bile acid level. Whereas the determination of standard laboratory parameters remains predominant in the description of liver cell damage, the importance of serum bile acid determination is seen in the description of functional liver disorders which are not characterized by increased enzyme activities. (orig.) [de

  12. Failure of ultracentrifugation as a means of separating plasma free insulin from immunoglobulin fraction prior to radioimmunoassay

    International Nuclear Information System (INIS)

    Escobar, L.J.; White, N.H.; Santiago, J.V.; Gingerich, R.L.

    1985-01-01

    It has been reported that ultracentrifugation of plasma will allow direct measurement of free insulin in the serum of diabetic subjects with insulin antibodies. To validate this method, the authors determined recovery of immunoreactive insulin and immunoglobulin G from the plasma of normal individuals after ultracentrifugation. The upper and middle fractions of plasma after ultracentrifugation were evaluated at several combinations of time and temperature. None of these conditions effectively removed all immunoglobulin G without causing concomitant loss of insulin. The authors conclude that ultracentrifugation of plasma prior to radioimmunoassay cannot be used to reliably determine free insulin concentration in the plasma from subjects with circulating insulin antibodies. (Auth.)

  13. Competitive radioimmunoassay of digoxin in serum

    International Nuclear Information System (INIS)

    Oslapas, Raymond; Herrin, T.R.

    1975-01-01

    The process described is for determining the digoxin level of a serum. To do so a mixture is made by adding to the serum sample an antidigoxin antibody and a suitable labelling quantity of O 3 -(hydroxy-4 phenethylcarbamoyl)digoxigenin for radioactive labelling. The mixture is allowed to incubate so that the digoxin of the sample and the radioactive labelling reagent joint to the antidigoxin antibody. A precipitating agent is added to the mixture to help the formation of a precipitate and thus separate the labelled digoxin taken up from the precipitate free digoxin. The liquid is separated from the precipitate formed and the residual radioactivity of the precipitate is measured [fr

  14. Setting-up and validation of two radioimmunoassay methods for determination of plasma progesterone concentration in mares, cows and rats; Padronizacao e validacao de dois metodos de radioimunoensaio (RIE) para dosagem da progesterona (P{sub 4}) no plasma de equinos, bovinos e ratos

    Energy Technology Data Exchange (ETDEWEB)

    Rosa e Silva, A.A.M.; Caldas, M.C.S.; Campos, L.M.A. [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Fac. de Medicina. Dept. de Fisiologia; Gradela, A. [UNESP, Jaboticabal, SP (Brazil). Faculdade de Ciencias Agrarias e Veterinarias

    1993-06-01

    Two reliable radioimmunoassay (RIA) methods which permits the measurement of progesterone (P{sub 4}) in plasma of equine, bovine and rats are described. After extraction of plasma with diethylic ether the RIA methods were performed. The first one utilizes {sup 125} I progesterone (double antibody method) and the other 1,2,6,7,16, 17 {sup 3} H progesterone (adsorption in charcoal/dextran). Both two methods were suitable in the valuation of plasma P{sub 4} concentration in different physiological reproductive conditions. The method of the double antibody showed higher sensibility beyond to be less expensive than the other method. Despite it, the two RIA methods were much less expensive than available commercial Kits in the market. (author) 14 refs., 2 figs., 1 tab.

  15. Specific and sensitive radioimmunoassay for 3-methoxy-4-hydroxyphenylethyleneglycol (MOPEG)

    Energy Technology Data Exchange (ETDEWEB)

    Keeton, T.K. (Univ. of Texas Health Science Center, San Antonio); Krutzsch, H.; Lovenberg, W.

    1981-02-06

    Antibodies that specifically bind the norepinephrine metabolite 3-methoxy-4-hydroxyphenylethyleneglycol (MOPEG) were produced in rabbits after injection of a derivative of MOPEG conjugated with bovine thyroglobulin. A sensitive radioimmunoassay was devised with this antiserum, in which as little as 0.5 nanogram of MOPEG can be accurately measured with a final antibody dilution of 1:180. The antibody appears to be specific for MOPEG, since tritiated MOPEG was not displaced from the antibodies by norepinephrine, epinephrine, dopamine, serotonin, or their major metabolites, including MOPEG-sulfate (333 nanograms each).

  16. Isotopic methods or immuno diagnosis: The Radioimmunoassay and immunoradiometric assay

    International Nuclear Information System (INIS)

    Caso, R.

    1997-01-01

    This work offers an explanation about the more used isotopic techniques for immuno diagnosis: the radioimmunoassay (RIA) and immunoradiometric assay (IRMA). It describes the basic principles of these assays, the antigen-antibody reaction, the radioiodination methods with I-125 for antigens and antibodies, the purification and characterization of labelled compounds. On the order hand they present work gives a review of the methods for separate the bound and free fractions. At the end it offers the principles of the quality control of immunoassay and the future lines of research in the field of RIA and IRMA

  17. An introduction to radioimmunoassay and related techniques. 3. rev. ed.

    International Nuclear Information System (INIS)

    Chard, T.

    1987-01-01

    This book is designed as an introductory text for the staff of clinical or research laboratories who conduct or intend to conduct radioimmunoassay and related immunoassay techniques, and will also be of great value to the clinicians who make use of such services. The emphasis is on general principles with practical illustrations rather than a detailed and encyclopaedic review of the literature. This 3rd revised edition places more emphasis on alternative labels (non-isotopic immunoassays), the use of labelled antibodies (immunometric assays), and the use of monoclonal antibodies. Both principles and practice are illustrated by diagrams and illustrations. (Auth.)

  18. Radioimmunoassay of serum β2-microglobulin in donor's blood

    International Nuclear Information System (INIS)

    Yin Shihua; Song Shiyun; Li Kelin; Chen Guanglian; Liu Fengmin

    1993-01-01

    Serum β 2 -microglobulin (β 2 -MG) was tested by radioimmunoassay in 149 donors' and 54 healthy volunteers' blood. The results were 203 +- 33.0 nmol/l and 176 +- 26.2 nmol/l, respectively. There was significant difference statistically between them (P 2 -MG content. In order to increase the quality of donated blood and to keep the health of blood donor, it is suggested that the high content of serum β 2 -MG is the indicator of too frequent blood donating. The results also showed that the content of β 2 -MG in donor's blood is not a normal reference value

  19. Chromatographic purification of tritiated steroids prior to use in radioimmunoassay

    International Nuclear Information System (INIS)

    Manlimos, F.S.; Abraham, G.E.

    1975-01-01

    The purity of tritiated steroids used as reagents in radioimmunoassay plays an important role in the reliability of the assay. These radioactive reagents should be assessed for purity upon receipt and the purity should be checked periodically afterward. For such purposes, we have used chromatographic purification on Celite microcolumns. By changing the polarity of the stationary and mobile phases, 20 different tritiated steroids with a wide range of polarity could be purified on these microcolumns. This approach is easy, rapid, economical, and reliable. (U.S.)

  20. Radioimmunoassay of somatostatin: methodological problems and physiological investigations

    International Nuclear Information System (INIS)

    Penman, E.; Wass, J.A.H.

    1981-01-01

    Somatostatin, a tetradecapeptide, has a wide distribution throughout the central nervous system and the gastrointestinal tract and a broad spectrum of biological actions. In order to investigate its various physiological roles in man, a radioimmunoassay was developed for somatostatin in human blood plasma, which is described here. This RIA was used to investigate possible factors influencing somatostatin secretion. Changes in somatin levels produced by changes in insulin, glucagon and growth hormone levels were studied via the response of plasma immunoreactive somatostatin to hormonal stimuli in normal man. The influence of fasting and food consumption was studied; and the site of origin of circulating immunoreactive somatostatin was investigated in patients. (Auth.)

  1. Radioimmunoassay of human muscle carbonic anhydrase III in dystrophic states

    International Nuclear Information System (INIS)

    Heath, R.; Jeffery, S.; Carter, N.

    1982-01-01

    A radioimmunoassay for the human isozyme carbonic anhydrase III (CAIII) has been developed. The assay can detect levels as low as 4μg/l of sample. Plasma CAIII levels in patients suffering from Duchenne muscular dystrophy were found to be up to 39 times greater than in a control group. Urine CAIII levels in patients suffering from Duchenne muscular dystrophy were not significantly different from the levels found in urine from normal adults. Measurement of plasma CAIII levels may be useful in prenatal diagnosis of Duchenne muscular dystrophy, and in investigation of adult skeletal muscle disease. (Auth.)

  2. Preparation and purification of 7-Iodoclonazepam for use in radioimmunoassay

    Energy Technology Data Exchange (ETDEWEB)

    Goddard, C.P.; Law, B.; Mason, P.A.; Stead, A.H.

    1986-04-01

    A method is described for the preparation and purification of 7-(/sup 125/I)-Iodoclonazepam (5-(o-Chlorophenyl)-2,3-Dihydro-7-(/sup 125/I)-Iodo-1H-1,4-Benzodiazepin-2-one). The structure was confirmed by mass spectrometry using 7-(/sup 127/I)iodoclonazepam prepared by the same method. 7-(/sup 125/I)-Iodoclonazepam binds well to a benzodiazepine antiserum. Although readily displaced by all the benzodiazepines commercially available in the UK, it is not displaced by structurally related nonbenzodiazepines except at very high concentrations. 7-(/sup 125/I) Iodoclonazepam should therefore be useful for the development of a screening radioimmunoassay (RIA) for benzodiazepines.

  3. Studies on digoxin derivatives in different biological media by radioimmunoassay

    International Nuclear Information System (INIS)

    Barmasch, Martha; Perez, L.N.; Altschuler, Noe.

    1978-05-01

    The fundamental aim of this study was to develop a methodology to be applied to pharmacological studies, directed to demonstrate the passage of digitalic compounds through the blood-brain barrier. This study was a comparative one between β methyl digoxin (βMD) and digitoxin (Dt). A methodology of radioimmunoassay was developed for different biological media: serum (S), plasma (P) and cerebro spinal fluid (CSF). In addition, the immunochemical behaviour (affinity, displacement, etc.) of βMD was studied when reacted with digoxin (D) and digoxin-antisera, supplied by the commercial kits utilized in these studies. (author) [es

  4. Radioimmunoassay test system for detection of anti-insulin antibodies

    International Nuclear Information System (INIS)

    Dudko, N.V.; Piven', N.V.; Ibragimova, G.V.; Kasatkin, Yu.N.

    1995-01-01

    A radiodiagnostic test system has been developed and commercial kit for radioimmunoassay of anti-insulin antibodies in human blood serum created. Clinical trials of the kit in patients (150 diabetics with types 1 and 2 condition) and normal subjects (n=100) demonstrated the possibility of using this kit for the detection of preclinical forms of diabetes and for distinguishing groups at risk of diabetes among children and adults, for the detection of insulin resistance, for the differential diagnosis of diabetes, and for monitoring the efficacy of insulin therapy. 9 refs.; 1 tab

  5. Radioimmunoassay and radioenzymatic assay of a new aminoglycoside antibiotic, netilmicin

    International Nuclear Information System (INIS)

    Broughton, A.; Strong, J.E.; Pickering, L.K.; Knight, J.; Bodey, G.P.

    1978-01-01

    A radioimmunoassay and a radioenzymatic assay for netilmicin, a new aminoglycoside, were developed in our laboratories to assist in the study of the pharmacology of the drug and establish values for use in its monitoring. The assays are sensitive, precise, and rapid, giving results that correlate (r = 0.90) with each other and with those of a microbiological assay in which Klebsiella pneumoniae is used as the test organism. Preliminary pharmacological studies show the drug to have a biological half-life of 135 min, which is comparable to that for other aminoglycosides

  6. Radioimmunoassay of total testosterone in urine of men

    International Nuclear Information System (INIS)

    Bilek, R.; Chundela, B.; Hampl, R.; Starka, L.

    1985-01-01

    The results are described and evaluated of the radioimmunoas radioimmunoassay of total testosterone in the urine in a sample of five men of the ages between 18 and 21 years. The levels of testosterone were related to creatinine in the urine in order to eliminate the effect of urine dilution. The analysis of the results showed that there exists a statistical difference between the levels of total testosterone related to creatinine in dependence on the time of sampling. The average value with standard deviation of total testosterone was 109 +- 41 ng testosterone/1 ml urine, 24.07 +- 8.33 pmol testosterone/1 μmol creatinine. (author)

  7. Use of progesterone radioimmunoassay techniques for improving reproduction performances in dary cattles

    International Nuclear Information System (INIS)

    Benyoucef, M.T.; Benabdelaziz, A.; Khelili, R.

    1990-07-01

    This report deals with the first measurements of progesterone, by radioimmunoassay (P4-PIA) in blood samples, to assess fertility in livestock (cattle) in Algeria, by improvement of the level of reproduction management. For this purpose, the results obtained throughout first analysis of P4 on a sample of 15 bovines females, composed by 12 heifers and 3 cows confirm the efficiency of the techniques in improving dary cattle reproduction performances. Ovarian activity can be determined for cows at the moment of post partum and for heifers before breeding as well as, pregnancy confirmation on breeding heifers. It is interesting to extend the experiments using these techniques to a higher number of livestocks (breeds and species) and to develop new research subjects in this field

  8. Comparison of different standards used in radioimmunoassay for atrial natriuretic factor (ANF)

    DEFF Research Database (Denmark)

    Rasmussen, Peter Have; Nielsen, M. Damkjær; Giese, J.

    1991-01-01

    , estimates of the ANF content in human plasma samples with different standard preparations as the reference showed a considerable variability. With the international standard as the gold reference (plasma ANF concentration 100%) the apparent plasma ANF concentrations measured with the other reference......Six different standards for determination of atrial natriuretic factor (ANF) in human plasma samples have been compared using our radio-immunoassay for ANF: International standard 85/669, National Biological Standard Boards, UK; Bachem standard, Torrance, USA; Bachem standard, Bubendorf......, Switzerland; Bissendorf standard, Wedemark, Germany; Peninsula standard, Belmont, USA; UCB-Bioproducts standard, Brussels, Belgium, Standard curves obtained with different preparations were in parallel but showed considerable quantitative differences. Standard curves referring to the Bissendorf standard...

  9. A simple and sensitive radioimmunoassay of insect juvenile hormone using an iodinated tracer

    International Nuclear Information System (INIS)

    Baehr, J.C.; Pradelles, Ph.; Lebreux, C.; Cassier, P.; Dray, F.

    1976-01-01

    Juvenile hormones (JH) + are acyclic sesquiterpenes involved in the growth and reproduction of insects. They are secreted by the 'corpus allatum', a small paired or fused gland located behind the brain. Ecdysone, a moulting hormone, initiates the moulting process and induces a larval molt with a high JH titer while the absence of JH is followed by an adult molt. In the adult, JH is secreted again and acts as a gonadotropic hormone by stimulating vitellogenesis and activities of the accessory glands. Bioassays and physicochemical assays have been developed to test for JH activity. The clear-cut success of the radioimmunological techniques should encourage the development of radioimmunoassay for juvenile hormone. The first tentative study using an homologous tritiated tracer did not permit a sensitive assay of JHsub(I). The production of specific JHsub(I) antibodies is reported as well as the synthesis of iodinated tracer which allows a simple and sensitive determination of this hormone in biological fluids

  10. The usefulness of serum LH radioimmunoassay in the diagnosis of male hypogonadism

    International Nuclear Information System (INIS)

    Sobieszczyk, S.

    1975-01-01

    Serum LH was determined in a group of 56 males with gandal insufficiency. In this group were included 20 cases of Klinefelter's syndronme, 14 patients with total anterior pituitary insufficiency and 22 patients with eunuchoidism. Serum LH was also performed in a group of 50 healthy men. In the presented studies the LH radioimmunoassay with double antibodies was applied. In most cases of Klinefelter's syndrome the concentration of LH in serum was increased but in four subjects was normal. In total hypopituitarism serum LH was undetectable. Among patients with eunuchoidism the results of serum LH concentrations were different. Three cases with anorchia as well as four patients with testicular atrophy had elevated serum LH. In the other fifteen subjects serum LH was undetectable; hypogonadotropic eunuchoidism was diagnosed in these patients. (author)

  11. Specificity and sensitivity of binding proteins in the radioimmunoassay of cortisol

    International Nuclear Information System (INIS)

    Gijzen, A.H.J.

    1977-01-01

    A comparison concerning avidity towards cortisol and 10 other steroids was made between several binding proteins either in solution or bound to cellulose as so called ''solid phase'' reagent. Human blood cortisol binding protein (CBP, transcortin), and two distinctly different cortisol-binding rabbit antisera and the isolated immunoglobulins thereof were compared in their avidity to bind cortisol and several other steroids. The antisera were harvested from rabbits immunized with either cortisol-21-succinyl-albumin (CSA) or cortisol-3-oxim-albumin (COA). The latter antiserum, having the highest titre in cortisol titration, showed the greatest specificity and was most useful as a binding reagent in cortisol radioimmunoassay when used as a solid phase reagent. The determination of cortisol in micro samples of blood serum is possible without steroid extraction or serum protein denaturation and with only minor influence of steroid impurities in the sample to be analyzed. Affinity constants for all compared binding reagents and steroids are given

  12. Radioimmunoassay (RIA) technique of steroid hormones in the laying hens, Gallus domesticus

    International Nuclear Information System (INIS)

    Ramli bin Abdullah

    1990-01-01

    The principle of radioimmunoassay (RIA) has been applied to many organic compounds of biological interest. In this work, commercially available antisera developed for various steroid hormones were used in the analysis of steroid hormones in the laying hens. The RIA procedure for plasma steroid hormones was divided into three phases: sample preparation, incubation of the antibody-3H-steroid complex with prepared samples and a standard curve and separation of antibody bound 3H-steroid from free 3H-steroid. Results showed that it is possible to use commercially available antiserum source for the determination of steroid hormones in this species. This approach has the advantage of savings in both time and money, by eliminating time losses in screening potential animals producing steroid antiserum and the costs of maintaining these animals

  13. A rapid radioimmunoassay for insulin suitable for testing pancreatic tissue prior to transplantation

    International Nuclear Information System (INIS)

    Besch, W.; Kohnert, K.-D.; Hahn, H.-J.; Ziegler, M.; Lorenz, D.

    1984-01-01

    One way of diabetes mellitus treatment is the transplantation of insulin-producing tissue. As islet or pancreas transplantation has made progress, testing of the tissue for its vitality, insulin content and insulin secretory response prior to transplantation became necessary. Apart from problems of rejection of allografted tissue, improvement of the patients metabolic control partly depends on the insulin content of the tissue transplanted. It was the aim of the present work to establish a radioimmunoassay which ensures rapid determination of immunoreactive insulin concentrations (IRI) either intracellularly-stored or released upon stimulation of human pancreas or islet with glucose, and to demonstrate the useful application of this assay for the assessment of transplantable tissue. (Auth.)

  14. Radioimmunoassay for progesterone in bovine milk; Radioinmunoensayo para progesterona en leche bovina

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz, Miriam [Instituto Superior de Ciencias y Tecnologia Nucleares, La Habana (Cuba)]. E-mail: mirian@fctn.isctn.edu.cu; Figueredo, Nancy; Castillo, Sonia; Pizarro [Centro de Isotopos, La Habana (Cuba)

    2002-07-01

    A system for the measurement of progesterone in bovine milk by radioimmunoassay has been developed and validated. This assay includes an iodine tracer purified by HPLC, the standard prepared in fat-free milk and an antibody anti-progesterone combined with second antibody. The detection limit of the assay is at 0.2 nmol/L calculated from the maximum binding menus two standard deviations and the precision is satisfactory. In the recovery assay was used 4 milk different samples and the result was 98% of recuperation. The progesterone was determinate in milk samples from post-partum animals taking samples three times per week for 40 days. The assay is simple, rapid and possibility the progesterone measurement without sample dilution, distinguish the cyclic changes of this hormone that reflect the ovarian activity in the animals. (author)

  15. Human epidermal growth factor: molecular forms and application of radioimmunoassay and radioreceptor assay

    International Nuclear Information System (INIS)

    Hirata, Y.; Orth, D.N.

    1981-01-01

    Epidermal growth factor (EGF), a 53 amino acid polypeptide, was first isolated by Cohen. EGF's growth-promoting activity is not limited to epidermal cells, but is expressed on a wide variety of tissues derived from a number of different species. Human EGF (hEGF) was isolated and subsequently purified from human urine. Unexpectedly, a close structural relationship was recognized between mEGF and human β-urogastrone. The authors recently developed both an homologous hEGF radioimmunoassay (RIA) and a radioreceptor assay (RRA) using a human placental membrane fraction. Using these assays, the molecular size of hEGF in human body fluids and tissues was evaluated, and partial characterization of a high molecular weight form of hEGF isolated from human urine was carried out. The concentrations of immunoreactive hEGF were also determined in human tissues and plasma after extraction either with cationic exchange chromatography or with immunoaffinity chromatography. (Auth.)

  16. Significance of tear β2-MG radioimmunoassay in herpes simplex keratitis

    International Nuclear Information System (INIS)

    Feng Zhuxu; Zhao Suzhen; Zhang Qiliang; Chen Fengfen; Tang Baoyi

    1994-01-01

    Levels of tear and serum β 2 -MG are determined with radioimmunoassay in 35 patients with herpes simplex keratitis and 40 normal subjects. The results show that tear β 2 -MG levels of patients with herpes simplex keratitis (13.21 +- 6.15 mg/l) and normal subjects (8.43 +- 1.52 mg/l) are significantly different (P 2 -MG levels of tear and that of serum in normal subjects (P 2 -MG levels of tear and that of serum in patients with herpes simplex keratitis (P 2 -MG levels of patients with herpes simplex keratitis and that of normal subjects (P>0.05). The β 2 -MG levels of tear is higher than that of serum in normal subjects which reflects more correctly immune condition of patients with herpes simplex keratitis than that of serum

  17. Radioimmunoassay of plasma vasopressin. Technique and applicaton to some clinical cases

    International Nuclear Information System (INIS)

    Granier, Francoise.

    1978-01-01

    The object of this work was to develop a sensitive and reliable radioimmunological determination of plasma vasopressin for routine use. Part one is devoted to an outline of the physiological aspects of antidiuretic hormone with emphasis on the vasopressin regulation and secretion mechanisms, especially osmotic regulation. Part two describes our analysis technique by successive stages and gives, for each point considered, a comparative review of the methods described in the literature. Part three reports our results obtained on normal subjects during dehydration tests and in some pathological cases. Our radioimmunoassay is similar to that of Robertson. In 2 observations of diabetes insipidus no detectable amount of vasopressin was measured in contradiction with the results obtained by most authors. On the whole our purpose has been fulfilled. However this work contains inadequacies which are underlined and will have to be corrected in later studies [fr

  18. Development of a solid phase technic for radioimmunoassay of triiodothyronine (T3) in serum

    International Nuclear Information System (INIS)

    Hamada, M.M.; Mesquita, C.H.; Silva, C.P.G. da.

    1988-10-01

    We have developed a solid phase radioimmunoassay (RIA) system for triiodothyronine (T 3 ), by immobilizing triiodothyronine antibodies on the inner wall of reaction tubes. The antibody-coated tubes were made via reaction of antibody with glutaraldeyde residue pre coated on the inner wall of the tubes by alkaline self-polimerization. The quality of the coated tubes was tested through its performance in the RIA methodology, by analysing the following RIA parameters: minimum detectable dose (MDD), nonspecific binding (NSB), ''X 50% '', slope of the standard curve, intra and inter-assay precision, accuracy of the method and figure of merit. The serum levels of T 3 in hypothyroid and hyperthyroid patients and the normal values range were determined for the solid phase RIA system. The results are in agreement with found in the literature. (author) [pt

  19. Programs for data processing in radioimmunoassay using the HP-41C programmable calculator

    International Nuclear Information System (INIS)

    1981-09-01

    The programs described provide for analysis, with the Hewlett Packard HP-41C calculator, of counting data collected in radioimmunoassays or other related in-vitro assays. The immediate reason for their development was to assist laboratories having limited financial resources and serious problems of quality control. The programs are structured both for ''off-line'' use, with manual entry of counting data into the calculator through the keyboard, and, in a slightly altered version, for ''on-line'' use, with automatic data entry from an automatic well scintillation counter originally designed at the IAEA. Only the off-line variant of the programs is described. The programs determine from appropriate counting data the concentration of analyte in unknown specimens, and provide supplementary information about the reliability of these results and the consistency of current and past assay performance

  20. Radioimmunoassay, acetylating radio-enzymatic assay, and microbioassay of gentamicin: a comparative study

    International Nuclear Information System (INIS)

    Stevens, P.; Young, L.S.; Hewitt, W.L.

    1975-01-01

    Gentamicin is an aminoglycoside antibiotic widely used to treat gram-negative bacillary infections. Because it has a low therapeutic index, monitoring of serum levels may help to insure adequacy of dosage and avoid toxicity. Microbiological assays are relatively slow and can be complicated by the presence of other antimicrobials. Radioimmunoassay (RIA) and acetylating radio-enzymatic assay (ARA) are new methods for gentamicin assay which offer the following advantages: rapidity (less than 3 hours); no interference by other antibiotics; RIA is extremely sensitive and ARA is versatile (being useful in the measurement of other aminoglycosides). Correlation coefficients determined by linear regression analysis of assays on 36 patient samples performed in duplicate on 2 different days demonstrated no significant difference in measurement of gentamicin by each of the methods. Factors such as numbers of specimens, cost, and time involved will affect the decision of the method to be applied in individual laboratories. (U.S.)

  1. 125I-radioimmunoassay of amikacin and comparison with a microbioassay

    International Nuclear Information System (INIS)

    Stevens, P.; Young, L.S.; Hewitt, W.L.

    1976-01-01

    A radioimmunoassay (RIA) has been developed using 125 I-amikacin. Amikacin was iodinated by a modified Bolton and Hunter method. Dextran-charcoal was used to separate bound from free drug. The standard curve was linear on a logit-log plot in the range of 0.5 ng to 4 ng amikacin per tube. There was no cross-reactivity of amikacin antisera to the aminoglycosides gentamicin, tobramycin, netilmicin, and sisomicin but a 70% cross-reaction was observed with kanamycin, the compound from which amikacin is synthetically derived. Correlation of the RIA with a microbioassay for the determination of serum amikacin levels in 18 patient samples was excellent (r=0.94). This new RIA technique is more sensitive, rapid, versatile, and less costly than the RIA using 3 H-amikacin, and is far more sensitive and faster than microbioassay. (auth.)

  2. Somatostatin signaling system as an ancestral mechanism: Myoregulatory activity of an Allatostatin-C peptide in Hydra.

    Science.gov (United States)

    Alzugaray, María Eugenia; Hernández-Martínez, Salvador; Ronderos, Jorge Rafael

    2016-08-01

    The coordination of physiological processes requires precise communication between cells. Cellular interactions allow cells to be functionally related, facilitating the maintaining of homeostasis. Neuropeptides functioning as intercellular signals are widely distributed in Metazoa. It is assumed that neuropeptides were the first intercellular transmitters, appearing early during the evolution. In Cnidarians, neuropeptides are mainly involved in neurotransmission, acting directly or indirectly on epithelial muscle cells, and thereby controlling coordinated movements. Allatostatins are a group of chemically unrelated neuropeptides that were originally characterized based on their ability to inhibit juvenil hormone synthesis in insects. Allatostatin-C has pleiotropic functions, acting as myoregulator in several insects. In these studies, we analyzed the myoregulatory effect of Aedes aegypti Allatostatin-C in Hydra sp., a member of the phylum Cnidaria. Allatostatin-C peptide conjugated with Qdots revealed specifically distributed cell populations that respond to the peptide in different regions of hydroids. In vivo physiological assays using Allatostatin-C showed that the peptide induced changes in shape and length in tentacles, peduncle and gastrovascular cavity. The observed changes were dose and time dependent suggesting the physiological nature of the response. Furthermore, at highest doses, Allatostatin-C induced peristaltic movements of the gastrovascular cavity resembling those that occur during feeding. In silico search of putative Allatostatin-C receptors in Cnidaria showed that genomes predict the existence of proteins of the somatostatin/Allatostatin-C receptors family. Altogether, these results suggest that Allatostatin-C has myoregulatory activity in Hydra sp, playing a role in the control of coordinated movements during feeding, indicating that Allatostatin-C/Somatostatin based signaling might be an ancestral mechanism. Copyright © 2016 Elsevier Inc. All

  3. Nutritional factors and preservation of C-peptide in youth with recently diagnosed type 1 diabetes: SEARCH Nutrition Ancillary Study.

    Science.gov (United States)

    Mayer-Davis, Elizabeth J; Dabelea, Dana; Crandell, Jamie L; Crume, Tessa; D'Agostino, Ralph B; Dolan, Lawrence; King, Irena B; Lawrence, Jean M; Norris, Jill M; Pihoker, Catherine; The, Natalie

    2013-07-01

    To test the novel hypothesis that nutritional factors previously associated with type 1 diabetes etiology or with insulin secretion are prospectively associated with fasting C-peptide (FCP) concentration among youth recently diagnosed with type 1 diabetes. Included were 1,316 youth with autoantibody-positive type 1 diabetes who participated in the SEARCH for Diabetes in Youth study (baseline disease duration, 9.9 months; SD, 6.3). Nutritional exposures included breastfeeding and age at introduction of complementary foods, baseline plasma long-chain omega-3 fatty acids including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), vitamin D, vitamin E, and, from a baseline food frequency questionnaire, estimated intake of the branched-chain amino acid leucine and total carbohydrate. Multiple linear regression models were conducted to relate each nutritional factor to baseline FCP adjusted for demographics, disease-related factors, and other confounders. Prospective analyses included the subset of participants with preserved β-cell function at baseline (baseline FCP ≥0.23 ng/mL) with additional adjustment for baseline FCP and time (mean follow-up, 24.3 months; SD, 8.2; n = 656). FCP concentration was analyzed as log(FCP). In adjusted prospective analyses, baseline EPA (P = 0.02), EPA plus DHA (P = 0.03), and leucine (P = 0.03) were each associated positively and significantly with FCP at follow-up. Vitamin D was unexpectedly inversely associated with FCP (P = 0.002). Increased intake of branched-chain amino acids and long-chain omega-3 fatty acids may support preservation of β-cell function. This represents a new direction for research to improve prognosis for type 1 diabetes.

  4. Comparison of radioimmunoassay and gas chromatographic mass spectrometric assay for d-amphetamine

    International Nuclear Information System (INIS)

    Powers, K.H.; Ebert, M.H.

    1979-01-01

    Quantification of low levels of psychotropic drugs (10 -7 to 10 -9 g ml -1 ) in small volumes of plasma requires sensitive and accurate methods. Validation of these methods is best achieved by comparing results obtained using several techniques. In this study, amphetamine levels in plasma were measured using gas chromatography mass spectrometry and radioimmunoassay. Correlation of the results obtained by the two methods was found to be positive and high (R = 0.9822). The average coefficient of variation between assays for gas chromatography mass spectrometry was 5.8% and for radioimmunoassay was 12.3%, while the average coefficient of variation within assays for gas chromatography mass spectrometry was 4.9% and for radioimmunoassay 6.9%. Although gas chromatography mass spectrometry was 1.9 times more sensitive than radioimmunoassay, for most purposes, the convenience of the radioimmunoassay method outweighs the technical superiority of gas chromatography mass spectrometry. (author)

  5. Non-equilibrium method for the radioimmunoassay of clozapine in the presence of metabolites

    International Nuclear Information System (INIS)

    Rosenthaler, J.; Nimmerfall, F.; Sigrist, R.; Munzer, H.

    1977-01-01

    Cross-reactions with metabolites are an ever-recurring problem encountered in the use of radioimmunoassay techniques to determine active compounds in biological material. Metabolites may interfere with the assay of the parent drug to a variable extent. Taking 8-chloro-11-(4-methyl-1-piperazinyl)-5H-dibenzo[b,e][1,4]diazepine (clozapine) as an example, it was shown that the extent to which the antiserum produced interacts with the parent drug and the metabolites can be estimated by determining the equilibrium constants and the kinetics. In the present case, therefore, it was advantageous to carry out the radioimmunoassay in disequilibrium, i.e. in order to differentiate the metabolites from the parent drug, the sample was incubated with the antiserum for 10 min, after which the labelled antigen was added and the reaction mixture again incubated for a brief, exactly timed interval. It was shown that cross-reactions did not occur in mixtures of clozapine and its N-demethyl and N-oxide metabolites in the proportions 1 : 1 : 2 over a range of concentration of 1.5-48 ng clozapine per 100 μl human plasma. The equilibrium constants measured with the clozapine goat antiserum were as follows: clozapine 1.2 x 10 8 M -1 , the N-demethyl metabolite 4.6 x 10 7 M -1 and the N-oxide 3.7 x 10 7 M -1 (pH 7.5 and 20 0 C). (orig.) [de

  6. Local production of donkey anti-rabbit's sera for human prolactin radioimmunoassay

    International Nuclear Information System (INIS)

    Hassan, Ammar Mohamed Elamin

    2001-11-01

    Pure Rabbit's IgG was used in this study to raise donkey anti rabbit's sera to be used as separating agent in radioimmunoassay. Two healthy donkeys have been immunized. The anti rabbit's sera have been titrated as (i) crude, (ii) purified and dialysed coupled to magnetic particles. Then this antibody was used as separating agent in a radioimmunoassay for measurement of human prolactin (PRL). Coupled Sudanese donkey and rabbit's sera (Sud-DARS) was used as 1/8 titre using chelsea RIA kit for human prolactin while 1/200 of liquid Sud-DARS was found to be the best titre using the Chinese kit. The best condition for estimation of the prolactin were optimized by determining the suitable incubation time and temperature. The assay can be done at room temperature but it should be incubated for 6 hours as recommended by the Chinese kit. Validity tests were done. The regression coefficients were 0.994 and 0.999 for linearity and recovery tests respectively. Measurement of human PRL wa found to be reproducible using Sud-DARS as separating agent since the coefficient of variation (C.V. %) was found to be less than 15% for both within batch and between assays. Comparing Sud D ARS to the Chinese kit, separating agent as reference agent, regression coefficient was found to be 0.977 which indicate that Sud-DARS can be used as separating agent. Prolactin in Sudanese subject was determined using the Chinese kit the Sud-DARS as separating agent. The ranges were 74-398 mIU/L in males and 102-414 mI/L in the preovulatory phase for the females while in the post ovulatory phase it was 114-442 mIU/L. Ovulation was confirmed by measurement of progesterone level 7 days before the next suspected mensuration. (Author)

  7. Radioimmunoassay of tumor markers in serum of patients with renal carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Cordoni-Voutsas, M.; Glaubitt, D.; Wagner, W.; Lichtenberg, T.

    1984-01-01

    Having noted an increased serum level of TPA and CEA in patients with renal carcinoma the authors extended these studies by using a larger number of tumor markers. In 15 patients (11 men and 4 women after menopause) aged 33 to 74 years who had renal carcinoma, among them 3 with tumor metastases, the serum concentration of TPA, CA 12-5, CEA, AFP, ferritin, prolactin, ..beta..-HCG, and ..beta../sub 2/-microglobulin was measured by radioimmunoassay. Monoclonal antibodies were used in the determination of serum CA 12-5 and CEA. In all patients surgical treatment, irradiation, or cytostatic therapy had not been performed. In serum the normal range was exceeded by TPA in 7 patients, CA 12-5 in 3, CEA and AFP in one each, ferritin in 12, prolactin in 2, and ..beta../sub 2/-microglobulin in 10 patients. In one man serum prolactin was reduced. Serum ..beta..-HCG was normal in all patients. According to these results serum ferritin, TPA, and ..beta../sub 2/-microglobulin are of great value as tumor markers in patients with renal carcinoma. In several patients the increase of serum ..beta../sub 2/-microglobulin may be ascribed partly to deterioration of renal function. As no consistent patterns of tumor markers in serum were observed it is recommended to determine several tumor markers and not only one of them during the follow-up of patients. Radioimmunoassays for measuring the serum level of tumor markers, especially ferritin, TPA, and ..beta../sub 2/-microglobulin, may considerably assist in the management of patients with renal carcinoma by providing early information about tumor recurrence or metastases.

  8. Radioimmunoassay of tumor markers in serum of patients with renal carcinoma

    International Nuclear Information System (INIS)

    Cordoni-Voutsas, M.; Glaubitt, D.; Wagner, W.; Lichtenberg, T.

    1984-01-01

    Having noted an increased serum level of TPA and CEA in patients with renal carcinoma the authors extended these studies by using a larger number of tumor markers. In 15 patients (11 men and 4 women after menopause) aged 33 to 74 years who had renal carcinoma, among them 3 with tumor metastases, the serum concentration of TPA, CA 12-5, CEA, AFP, ferritin, prolactin, β-HCG, and β/sub 2/-microglobulin was measured by radioimmunoassay. Monoclonal antibodies were used in the determination of serum CA 12-5 and CEA. In all patients surgical treatment, irradiation, or cytostatic therapy had not been performed. In serum the normal range was exceeded by TPA in 7 patients, CA 12-5 in 3, CEA and AFP in one each, ferritin in 12, prolactin in 2, and β/sub 2/-microglobulin in 10 patients. In one man serum prolactin was reduced. Serum β-HCG was normal in all patients. According to these results serum ferritin, TPA, and β/sub 2/-microglobulin are of great value as tumor markers in patients with renal carcinoma. In several patients the increase of serum β/sub 2/-microglobulin may be ascribed partly to deterioration of renal function. As no consistent patterns of tumor markers in serum were observed it is recommended to determine several tumor markers and not only one of them during the follow-up of patients. Radioimmunoassays for measuring the serum level of tumor markers, especially ferritin, TPA, and β/sub 2/-microglobulin, may considerably assist in the management of patients with renal carcinoma by providing early information about tumor recurrence or metastases

  9. Radioimmunoassay of serum digoxin levels. Clinical exploration

    International Nuclear Information System (INIS)

    Galland, F.; Geslin, P.; Kerjean, J.; Six, P.; Tadei, A.; Jallet, P.

    1982-01-01

    This work undertakes, in a second part, the clinical exploration of 947 serum digoxin levels of 281 hospitalized patients on a cardiology ward. Our results, which coincide with those of other researchers, have led us to draw certain practical conclusions: the posology is determined first of all according to kidney function, weight and age of the patient. When the treatment is insufficient or, on the other hand, poorly tolerated, a serum digoxin level is performed permitting thus: in the case of ineffective treatment: to be sure of the patient's cooperation, to increase the posology if the serum digoxin level is not in the toxic zone, to discover an eventual pharmacokinetic problem; to establish the responsability of digitalis (when there are signs of intolerance or of intoxication), in case of arrhythmia, in patients with pacemakers, when associated drugs are capable of causing similar adverse effects; to better manage a digitalis treatment in a high risk patient (unstable renal function, advanced myocardial disease, chronic obstructive disease) [fr

  10. The development of a general solid-phase radioimmunoassay method. Application to follicle stimulating hormone and to luteinizing hormone radioimmunoassays

    International Nuclear Information System (INIS)

    Fleury, B.

    1981-10-01

    A solid phase method of radioimmunoassay utilizing a second antibody adsorbed onto tubes was developed. Polyethylene tubes were selected for their adsorption capacity. The following topics were emphasized: the rate of labelled antigen uptake on the second antibody adsorbed on the tubes through the medium of the first antibody; the influence of the second antibody on the antigen-first antibody reaction and comparison with the immunoprecipiting technique; the various factors able to influence the calibration curve and applications to assay optimization; the performances of hFSH AND hLH assays [fr

  11. Dessert Formulation Using Sucralose and Dextrin Affects Favorably Postprandial Response to Glucose, Insulin, and C-Peptide in Type 2 Diabetic Patients

    OpenAIRE

    Argyri, Konstantina; Sotiropoulos, Alexios; Psarou, Eirini; Papazafiropoulou, Athanasia; Zampelas, Antonios; Kapsokefalou, Maria

    2013-01-01

    BACKGROUND: Dessert compositions may conform to diabetic diet when it contains low sugar or artificial sweetener to replace sugar. However, it is still questionable whether glycemic control in type 2 diabetes patients is improved by the use of diet-conforming dessert compositions. OBJECTIVE: To compare, in type 2 diabetes patients, the glycemic, insulin, and C-peptide responses to seven modified dessert compositions for diabetics (D-dessert) with the response to seven similar desserts of non-...

  12. Structural basis for distinctive recognition of fibrinogen [gamma]C peptide by the platelet integrin [alpha][subscript IIb][beta]3

    Energy Technology Data Exchange (ETDEWEB)

    Springer, Timothy A.; Zhu, Jianghai; Xiao, Tsan (Harvard-Med)

    2009-01-12

    Hemostasis and thrombosis (blood clotting) involve fibrinogen binding to integrin {alpha}{sub IIb}{beta}{sub 3} on platelets, resulting in platelet aggregation. {alpha}{sub v}{beta}{sub 3} binding fibrinogen via an Arg-Asp-Gly (RGD) motif in fibrinogen's {alpha} subunit. {alpha}{sub IIb}{beta}{sub 3} also binds to fibrinogen; however, it does so via an unstructured RGD-lacking C-terminal region of the {gamma} subunit ({gamma}C peptide). These distinct modes of fibrinogen binding enable {alpha}{sub IIb}{beta}{sub 3} and {alpha}{sub v}{beta}{sub 3} to function cooperatively in hemostasis. In this study, crystal structures reveal the integrin {alpha}{sub IIb}{beta}{sub 3}-{gamma}C peptide interface, and, for comparison, integrin {alpha}{sub IIb}{beta}{sub 3} bound to a lamprey {gamma}C primordial RGD motif. Compared with RGD, the GAKQAGDV motif in {gamma}C adopts a different backbone configuration and binds over a more extended region. The integrin metal ion-dependent adhesion site (MIDAS) Mg{sup 2+} ion binds the {gamma}C Asp side chain. The adjacent to MIDAS (ADMIDAS) Ca{sup 2+} ion binds the {gamma}C C terminus, revealing a contribution for ADMIDAS in ligand binding. Structural data from this natively disordered {gamma}C peptide enhances our understanding of the involvement of {gamma}C peptide and integrin {alpha}{sub IIb}{beta}{sub 3} in hemostasis and thrombosis.

  13. A specific and sensitive radioimmunoassay for human choriogonadotropin

    International Nuclear Information System (INIS)

    Muralidhar, K.; Chaudhuri, G.; Lippes, J.; Bahl, O.P.

    1983-01-01

    A specific and sensitive radioimmunoassay for human choriogonadotropin (hCG) has been developed using rabbit antiserum to chemical analogs of beta subunit of human chorionic gonadotropin prepared by controlled reduction and S-alkylation of its disulfied linkages. The assay was highly specific for hCG as the binding of [ 125 1]-hCG to the antibody was not affected by standard human lutropin, by human male serum, postpartum serum from women, serum from post-menopausal women and human menopausal gonadotropin (Pergonal). The assay was highly sensitive, the minimal detection limit in terms of highly purified hCG (L-129, 12.500 IU/mg) being 1 ng/ml or 0.2 ng/tube (or 12 mlU/ml in terms of WHO 2nd international reference preparation of hCG). Using this assay we were unable to detect any immunoreactive hCG in human tissues like lung, liver and colon. The high specificity, sensitivity, accuracy and reproducibility of the assay make this a highly desirable radioimmunoassay for human choriogonadotropin. (orig.)

  14. Secretin-radioimmunoassay, physiology and pathophysiology in man

    International Nuclear Information System (INIS)

    Haecki, W.H.

    1978-01-01

    Production of antibodies to secretin for radioimmunoassay is straightforward. Secretin is iodinated by weak oxydation with lactoperoxydase and subsequent purification by ionexchange chromatography (Sephadex C25). The specific activity of fresh label is between 650 and 900 mCi x mol -6 . The label is highly purified and may be used in radioimmunoassay for several months. In order to eliminate plasma interference sepharose-beads with covalently coupled secretin antibodies are used to produce secretin-free standard plasma samples. Delay in the separation of plasma from fresh blood samples can lead to erronous results, even to falsely elevated secretin levels. - Duo-denal acidification only leads to physiological increases of secretin plasma levels. This may happen by intraduodenal instillation of acid, or by an acidic oral drink, or to a lesser extent after a meal. Secretin is distributed throughout the plasma volume and has a short halflife of around 3 minutes. Impaired release of secretin is found in children with coeliac disease. The role of secretin in peptic ulcer however is not clear. Chronic pancreatitis and renal insufficiency are without effect on plasma secretin levels. (orig.) [de

  15. Radioimmunoassay of alpha-foetoprotein in the eluate of dried blood. A method for antenatal screening of neural tube defects

    International Nuclear Information System (INIS)

    Travert, G.; Herlicoviez, M.; Laroche, D.

    1979-01-01

    A radioimmunoassay for alpha-foetoprotein (AFP) in dried blood spots is reported. The main technical characteristics (reproducibility, sensitivity, recovery of exogenous AFP added and AFP stability in dried blood) are evaluated. They indicate that this method is feasible and well adapted to AFP measurement during pregnancy. AFP determination in maternal serum allows early detection of at least 80% of neural tube defects. The use of dried blood spots as samples for AFP assay makes our method a possible mass screening test for these malformations, which occur with an incidence of 12 for 10,000 [fr

  16. Isolation and purification of G immunoglobulin from guinea-pig for the production of a second antibody for radioimmunoassay

    International Nuclear Information System (INIS)

    Silva, S.R.; Borghi, V.C.; Bellini, M.H.; Wajchenberg, W.A.J.

    1992-01-01

    The IgG of guinea-pig was isolated and purified by precipitation with caprylic acid and the batch absorption with DEAE-cellulose. The efficiency of the operating was verified by the determination of total proteins, during the purification stages. The purity of the end product was proved by immuno electrophoresis face to rabbit serum total antiserum of guinea-pig. it was obtained 240 mg of purity IgG to be used in the production of second specific antibody for radioimmunoassay. (C.G.C.)

  17. Development of a double-antibody radioimmunoassay for detecting ovarian tumor-associated antigen fraction OCA in plasma

    International Nuclear Information System (INIS)

    Knauf, S.; Urbach, G.I.

    1978-01-01

    Ovarian tumor-associated antigen isolated from human tumor tissue was shown to have a different mobility from that of carcinoembryonic antigen (CEA) in both acrylamide gel electrophoresis and immunoelectrophoresis in agarose. The ovarian tumor antigen is composed of six species with different electrophoretic mobility in acrylamide gel electrophoresis. Three of these species were detected in Sephadex G-100 ovarian fraction OCA (from the void volume peak) and the other three species of lower apparent molecular weight were detected in fraction OCD (from the second peak). Fractions OCA and OCD did not share common antigenic determinants as determined by immunodiffusion. CEA was shown to share antigenic determinants with both OCA and OCD. A double-antibody radioimmunoassay capable of detecting nanogram quantities of plasma OCA was developed. In a preliminary study of ovarian cancer patients, OCA appeared to be a more sensitive marker for ovarian cancer than CEA. There was virtually no correlation (r 2 = 0.1) between OCA and CEA levels in these patients, as determined by radioimmunoassay

  18. Radioimmunoassay method suitable for analysis of salivary cortisol in patients with breast cancer in treatment by teletherapy - a preliminary study

    International Nuclear Information System (INIS)

    Souza, Kellen Verena S.; Santos, Jane Lima dos

    2011-01-01

    Determination of salivary cortisol using radioimmunoassay and the relationship between stress levels were investigated before and after of the psychological intervention of 21 patients during teletherapy treatment of breast cancer. The benefits of psychological intervention during cancer treatment has been observed in some studies and evidence show that the patient's emotional state directly influences adherence to treatment, good prognosis and under stress. Thus, in present study 21 patients aged 50-70 years, females in the treatment of breast cancer at the Radiotherapy Service of Santa Casa de Misericordia in Belo Horizonte, were divided randomly into two groups: control (without psychological intervention) and Group TCC (with psychological intervention). Salivary cortisol concentrations are reportedly about 5.10% of those in serum, the levels has been used as an objective marker of hypothalamic-pituitary-adrenal (HPA) axis activity and avoided the confounding effects of venepuncture stress on cortisol levels. The assessment of cortisol in saliva has proven a valid and reliable measure of unbound steroid in the circulation. The salivary cortisol measured by radioimmunoassay in control patients and TCC showed no significant differences. The radioimmunoassay method show be suitable for analysis of salivary cortisol because allows measure low detection limits and have high sensibility. The values of TCC group and Control group were higher than reference values, except for one patient of the control group. At the beginning of treatment, both groups were homogeneous for Teletherapy. Both the TCC group as the control group had . 80% of participants in phase with stress. It was observed in the TCC group after radiotherapy showing a reversal 60% of participants without stress. The data show that cognitive-behavioral therapy has benefits for the control of psychological stress and enhance relevance of the psychologist to provide reduction or stress control during

  19. Radioimmunoassay method suitable for analysis of salivary cortisol in patients with breast cancer in treatment by teletherapy - a preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Kellen Verena S. [Departamento de Engenharia Nuclear. Universidade Federal de Minas Gerais, Pampulha, MG (Brazil); Santos, Jane Lima dos [Departamento de Ciencias Biologicas, Universidade Estadual de Santa Cruz, Ilheus, BA (Brazil)

    2011-07-01

    Determination of salivary cortisol using radioimmunoassay and the relationship between stress levels were investigated before and after of the psychological intervention of 21 patients during teletherapy treatment of breast cancer. The benefits of psychological intervention during cancer treatment has been observed in some studies and evidence show that the patient's emotional state directly influences adherence to treatment, good prognosis and under stress. Thus, in present study 21 patients aged 50-70 years, females in the treatment of breast cancer at the Radiotherapy Service of Santa Casa de Misericordia in Belo Horizonte, were divided randomly into two groups: control (without psychological intervention) and Group TCC (with psychological intervention). Salivary cortisol concentrations are reportedly about 5.10% of those in serum, the levels has been used as an objective marker of hypothalamic-pituitary-adrenal (HPA) axis activity and avoided the confounding effects of venepuncture stress on cortisol levels. The assessment of cortisol in saliva has proven a valid and reliable measure of unbound steroid in the circulation. The salivary cortisol measured by radioimmunoassay in control patients and TCC showed no significant differences. The radioimmunoassay method show be suitable for analysis of salivary cortisol because allows measure low detection limits and have high sensibility. The values of TCC group and Control group were higher than reference values, except for one patient of the control group. At the beginning of treatment, both groups were homogeneous for Teletherapy. Both the TCC group as the control group had . 80% of participants in phase with stress. It was observed in the TCC group after radiotherapy showing a reversal 60% of participants without stress. The data show that cognitive-behavioral therapy has benefits for the control of psychological stress and enhance relevance of the psychologist to provide reduction or stress control during

  20. Production of biological reagents for radioimmunoassay second antibody

    International Nuclear Information System (INIS)

    Borghi, V.C.; Silva, S.R. da; Bellini, M.H.; Lin, L.H.

    1992-02-01

    The experimental production of second antibody to be used in hormonal assays, in which the first antibody is raised in rabbits, is described. Four sheep were immunized with the rabbit immunoglobulin prepared at IPEN-CNEN laboratory. Their antisera were evaluated by the human thyrotropin radioimmunoassay employing materials provided by the National Hormone and Pituitary Program (USA), in comparison with a reference antiserum of known quality, produced in goat by the Radioassay Systems Laboratories - RSL (USA). From the fourth booster injection the animals developed antiserum with titer similar to that exhibited by the commercial product, even presenting higher values. These antisera are now being examinated for the optimal conditions of precipitation before be packed for future use and distribution. (author)

  1. Development of a heterologus radioimmunoassay for human prolactin (hprl)

    International Nuclear Information System (INIS)

    Kothari, K.K.; Meera, V.; Soman, P.D.; Lal, R.; Sivaprasad, N.

    1991-01-01

    The development of a heterologous radioimmunoassay for the measurement of human prolactin in serum is reported. The assay uses the less expensive ovine prolactin for the preparation of 125 I labelled prolactin and anti prolactin serum while the human prolactin in used as standard. The assay is based on a double antibody- polyethylene glycol separation system for the separation of the antibody bound antigen from the free antigen. The optimized assay has a preincubation of the antibody with the cold antigen for 18 hours followed by a post incubation of 3 hours with the tracer. The sensitivity of this assay is 2ng/mL. The inter and intra assay variations are less than 9%. The values of the serum samples analysed by this method compares well with immunoradiometric assay. (author). 12 refs. , 6 figs., 2 tabs

  2. Development and characterization of a homologous radioimmunoassay for equine prolactin

    International Nuclear Information System (INIS)

    Roser, J.F.; Chang, Y.S.; Papkoff, H.; Li, C.H.

    1984-01-01

    A specific and sensitive homologous radioimmunoassay has been developed for equine prolactin, suitable for measuring prolactin concentrations in serum of horses. The sensitivity of the assay ranged from 0.4 to 0.6 ng/ml and the intra- and inter-assay coefficients of variation averaged 6.9 and 15.4%, respectively, for five doses of hormone. Cross-reactivity with other mammalian and nonmammalian prolactins and growth hormones was less than 20 and 0.3%, respectively. Cross-reactivity with equine growth hormone was less than 0.07%. Equine serum and pituitary extracts showed parallel dilution-response curves with equine prolactin. The percentage recovery of exogenous equine prolactin in serum was 89%. Preliminary analysis of several physiological samples (stallions, pregnant, and nonpregnant mares) yielded values from 0.6 to 12.0 ng/ml

  3. The milk samples collected with filter paper for progesterone radioimmunoassay

    International Nuclear Information System (INIS)

    Zhang Jiahua; Geng Guoxia; Zhang Huaiyu

    1985-01-01

    The cow milk was collected with filter paper treated with ethanol during eastrus-day (0 day) and 22th and 24th day after mating. Then it was dried and stored in room temprature until analysis for progesterone by means of radioimmunoassay. The sensitivity is 13.62 pg/bule (n = 4), the coefficients of variation within a group and between groups are 8.8% (n = 10) and 16.65% (n = 8) respectively, and the recovery is 91.23% (n = 4). The average progesterone level for 22th and 24th day in the pregnant cows (6.28 +- 1.28 ng/ml) was much higher than that in the non-pregnant cow (2.00 +- 1.18 ng/ml), the difference being significant (P < 0.001). The judgement based on progesterone level (5 pregnant and 5 non-pregnant cows) faily agreed with the clinical diagnosis

  4. Farm application of radioimmunoassay technology in dairy cattle management

    International Nuclear Information System (INIS)

    Alejandrino, A.L.; Asaad, C.O.; De Vera, A.C.; Deocaris, C.C.; Ignacio, L.M.; Herrera, M.S.; Mateo, A.B.

    1996-01-01

    Monitoring of progesterone concentrations in milk or blood plasma of farm animals, using radioimmunoassay technology is presented in this report. This was instituted among 103 dairy cows managed by dairy cooperatives under smallholder level in Sta. Cruz-Pagsanjan, Laguna and Sariaya, Quezon (n=103), and under communal level Pontevedra, Capiz (n=48). The authors observed that the measurement of progesterone in milk/plasma was proven useful as a diagnotic aid in dairy cattle production studies such as: (a) early pregnancy diagnosis; (b) identification of fertile and abnormally cycling/subestrus or anestrous cows, and (c) appropriate timing for breeding services especially at post-partum stage. This information is relevant where appropriate management intervention measures are indicated to improve dairy cattle production in the country. (author)

  5. Radioimmunoassay data processing program for IBM PC computers

    International Nuclear Information System (INIS)

    1989-06-01

    The Medical Applications Section of the International Atomic Energy Agency (IAEA) has previously developed several programs for use on the Hewlett-Packard HP-41C programmable calculator to facilitate better quality control in radioimmunoassay through improved data processing. The program described in this document is designed for off-line analysis using an IBM PC (or compatible) for counting data from standards and unknown specimens (i.e. for analysis of counting data previously recorded by a counter), together with internal quality control (IQC) data both within and between batch. The greater computing power of the IBM PC has enabled the imprecision profile and IQC control curves which were unavailable on the HP-41C version. It is intended that the program would make available good data processing capability to laboratories having limited financial resources and serious problems of quality control. 3 refs

  6. Provision of radioimmunoassays for reproductive hormones in developing countries

    International Nuclear Information System (INIS)

    Sufi, S.B.; Donaldson, A.; Jeffcoate, S.L.; Goncharov, N.P.

    1986-01-01

    The Special Programme of Research, Development and Research Training in Human Reproduction of the World Health Organization (WHO) has, for the last eight years, distributed sets of matched assay reagents for the radioimmunoassay of hormones to approximately 75 laboratories in 45 countries. The Matched Reagent Programme has enabled these centres to carry out research that would otherwise have been difficult, if not impossible, for them to undertake. Between-centre comparability, as judged by WHO External Quality Assurance Scheme data, has improved and at least five hundred scientific papers have been published as a consequence of the availability of WHO reagents. National and regional reagent programmes and associated schemes are being encouraged. These activities should help to improve the availability of research and diagnostic facilities for patient care in developing countries, which is consistent with the WHO policy of technology transfer. (author)

  7. Radioimmunoassay for chlorpromazine in plasma. [/sup 3/H tracer technique

    Energy Technology Data Exchange (ETDEWEB)

    Midha, K.K.; Loo, J.C.K.; Hubbard, J.W.; Rowe, M.L.; McGilveray, I.J.

    1979-01-01

    A radioimmunoassay for chlorpromazine in plasma is described. The antiserum was obtained by immunizing rabbits with a conjugate of bovine serum albumin and N-(2-carboxyethyl)desmethylchlorpromazine. It is specific for chlorpromazine and its minor active metabolite, N-desmethylchlorpromazine. Other known active or inactive chlorpromazine metabolites and other psychotropic drugs tested do not cross react with the antiserum. Less than 34 pg of the drug can be detected in 200 ..mu..L of plasma. As many as 100 samples can be processed in a day by one technician. Concentrations of chlorpromazine can be measured in 200-..mu..L samples of plasma collected as late as 48 h after a single oral 25-mg dose.

  8. Radioimmunoassay for human plasma 8-arginine-vasopressin

    International Nuclear Information System (INIS)

    Conte-Devolx, B.; Rougon-Rapuzzi, G.; Millet, Y.

    1977-01-01

    A radioimmunoassay for human plasma vasopressin (AVP) which permits the estimation of antidiuretic hormone (ADH) level as low as 0.8pg/ml, was developed. The average plasma level of AVP after overnight water restriction was found to be 14.3pg/ml (sd=4.4pg/ml) in normal subjects. They provoked a hypersecretion of ADH by the intravenous injection of 1-2mg of nicotine. In 11 volunteer normal subjects this stimulation by nicotine provoked ADH hypersecretion which reached a maximum between 2nd and 15th minutes after injection. In 3 cases of diabetes insipidus, nicotine injection did not induce ADH hypersecretion: in 1 case of potomania this response was weak; in 2 cases of syndrome of inappropriate ADH secretion, AVP plasma levels were elevated and the response after nicotine stimulation was exaggerated [fr

  9. Production of Anti-triiodothyronine sulfate antibody for radioimmunoassay applications

    International Nuclear Information System (INIS)

    Elbanna, I.M.; Ragab, M.T.

    2000-01-01

    Triiodothyronine sulfate (T3S) may be an obligatory intermediate metabolic of the metabolism of thyroid gland hormones invertebrates in peripheral during the process of deiodination of the inactive form of the thyroid gland hormones, thyroxine(T4), into the active form triiodothyronine (1,2). Construction of a reliable procedure for the estimation of T3S accurately in blood serum will be of great importance for medical, biochemical and physiological investigations. In this work we developed a robust method for the production of anti-triiodothyronine sulfate polyclonal antiserum with good specifications using a derivatized immuno gen and a modified immunization process and a sensitive radioimmunoassay system was designed and developed

  10. The measurement of platelet activation by radioimmunoassay in asthma

    International Nuclear Information System (INIS)

    Wu Guoxin; Sun Jian; Li Jianyong; Ruan Changgeng

    1992-02-01

    Radioimmunoassay with specific monoclonal antibody was used to evaluate the platelet activation in 14 cases of acute bronchial asthma. The result showed that the number of molecules of alpha-granule membrane protein (GMP-140) which was exposed on the surface of platelet following secretion significantly increased on the surface of platelet and in plasma, while the number of molecules of glycoprotein (GP) I b and GPIII a did not change significantly; the concentration of thromboxane B 2 in plasma was raised, while the concentration of 6-keto-PGF 1a was within the normal limits; the concentrations of β-thromboglobulin (β-TG) and platelet factor 4(PF 4 ) in plasma increased significantly; the number of platelets decreased. These results strongly confirmed that the degree of platelet activation was enhanced during acute asthmatic attack. The significance of platelet activation in the pathogenesis of asthma should be further investigated

  11. An improved radioimmunoassay for urinary Tamm-Horsfall glycoprotein

    International Nuclear Information System (INIS)

    Dawnay, A.B. St. J.; Thornley, C.; Cattell, W.R.

    1982-01-01

    A rapid specific radioimmunoassay has been used to measure Tamm-Horsfall glycoprotein (TH glycoprotein) in urine, and the method described. The apparent concentration increased with increasing dilution of urine in water, reaching a plateau at 1 in 20. This increase was greater the higher the osmolality and TH glycoprotein concentration and the lower the pH of the original sample. The apparent concentration of TH glycoprotein in neat or diluted urine was not affected by freezing or by storage at 4 0 C or room temperature for at least 2 days. A physiological range for the urinary excretion rate was established as 22-56 mg/24h, (considerably higher than the amount present in serum) based on samples from 29 individuals with normal renal function, as defined by their creatinine clearance. There was no significant correlation between serum concentrations of TH glycoprotein and its urinary excretion rate, nor between urinary excretion rate and creatinine clearance. (author)

  12. Recombinant-derived chicken growth hormone used for radioimmunoassay

    International Nuclear Information System (INIS)

    Proudman, J.A.

    1984-01-01

    The use of recombinant-derived chicken growth hormone (rcGH) in an avian growth hormone (GH) radioimmunoassay (RIA) procedure is described. Antiserum to turkey GH bound 125 I-labeled rcGH, and unlabeled rcGH or turkey GH displaced binding in a dose-related manner. The dose-response curves of sera and pituitary extract from chickens and turkeys were parallel to the rcGH standard curve. Sera from hypophysectomized (hypox) chickens and turkeys produced no dose-response and did not inhibit binding of labeled rcGH. Recovery of rcGH added to hypox sera was quantitative. Modification of the homologous turkey GH RIA protocol of Proudman and Wentworth (1) to use rcGH made possible either an increase in assay sensitivity or a 3-day reduction in incubation time

  13. High molecular somatostatin, an interfering factor in radioimmunoassay

    International Nuclear Information System (INIS)

    Diel, F.; Schneider, E.; Baumann, H.

    1977-01-01

    Cyclic Tyr 1 -somatostatin (Tyr 1 -SRIF) is radioiodinated by the lactoperoxidase method. Purification is achieved by Sephadex G-25 adsorption chromatography. Specific anti-SRIF serum (FA1) has been raised in rabbits. A dose response curve is obtained in the range of 5 - 5,000 pg per tube using an antiserum dilution of 1:2,000. There is little cross-reaction with linear somatostatin and none with ocytocin, (lys-, arg-) vasopressin, valinomycin, polymyxin, insulin, glucagon, human growth hormone (hGH), and thyrotropin-releasing hormone (TRH). For recovery tests, extraction procedures are necessary. Thin-layer chromatography (TLC) and polyacrylamide-disc-electrophoresis (Disc-PAGE) are performed to identify the presumed high molecular 125 I-Tyr 1 -SRIF associate. This high molecular associate may represent an interfering factor in the radioimmunoassay for cyclic SRIF. (orig./AJ) [de

  14. Engineering of radioimmunoassay (RIA) IP10.1

    International Nuclear Information System (INIS)

    Hari Nurcahyadi

    2010-01-01

    Engineering of Radioimmunoassay (RIA) IP10.1 is an innovative by PRPN - BATAN in 2010. Innovations made to the device IP10.1 RIA is the sample changer system, sample changer system on the device RIA IP10.1 applied 2 linear axis system (X, Z) with AC servo motor. In the RIA IP10.1 also use 5 pieces of the detector, so the enumeration process 50 (Fifty) sample is expected to be faster. Like its predecessor, The whole enumeration, data collection procedures and mechanisms operating within this system is entirely controlled by a PC via an electronic module. Electronics module consists of a high voltage module, amplifier and signal processor module, the module enumerators, low-voltage module, the module driver motor controller and a USB interface. The data acquisition and communication system using a USB port with the computer. (author)

  15. Radioimmunoassay for phencyclidine: application to kinetic analysis in the rat

    International Nuclear Information System (INIS)

    Ward, D.P.; Trevor, A.J.

    1980-01-01

    We report the development of a radioimmunoassay for phencyclidine (PCP) that is simple, rapid and sensitive to 0.5 ng/ml. Antibodies were raised in rabbits against the hapten, N-succinyl-3-aminophencyclidine. These antibodies proved to be very specific for PCP and exhibited less than 4% cross reactivity with the drug's two major metabolites. The assay was used for kinetic analysis of PCP in the rat following subcutaneous injection of 5 mg/kg of the drug. Serum and brain tissues were analyzed for PCP and the respective half lives were calculated to be 36 and 29 min for the α phase and 130 and 121 min for the β phase. The accuracy of the method was verified by concomitant assay of a number of kinetic samples by gas chromatography employing a nitrogen-phosphorus detector

  16. Effect of radioimmunoassay procedures on therapeutic drug monitoring

    International Nuclear Information System (INIS)

    Kampa, I.S.

    1985-01-01

    Methods for the measurement of therapeutic drugs have covered every aspect of analysis from extraction to derivatization. In general, published methods were modified to shorten drug extractions and overall analysis time. The use of different standards, as well as the frequent omission of internal standards, often produced large and clinically unacceptable analytical variations. As a result, physicians would adjust drug dosages according to the physiological response to a standard dose. The introduction of radioimmunoassay techniques for the quantitation of therapeutic drugs have made a significant impact on the clinical chemistry laboratory. The similarities of the various assay methods and the technologists' familiarity with the assay protocols have produced clinically relevant results. Clinical laboratories are now able to frequently analyze a large number of samples with acceptable accuracy and precision. The esoteric test once performed infrequently is today a routine analytical assay often performed STAT. Therapeutic drug monitoring has become a major activity in many clinical laboratories

  17. Development of a radioimmunoassay for triamcinolone acetonide in horse plasma

    International Nuclear Information System (INIS)

    Gylstorff, B.

    1982-01-01

    A radioimmunoassay (RIA) was developed for the detection of triamcinolone acetonide (TAAc) in equine blood plasma. These antibodies exhibited cross reactions of 0,015% with cortisol and of 0,1% with other endogenous glucocorticoids. Four different synthetic corticosteroids interfered in a range of 0,21 to 0,93%. In vitro 86 of TAAc could be recovered. This method proved sufficient reproducibility down to a limit of 131,7 fmol/ml = 57,2 pg/ml. The TAAc RIA is suitable for the detection of a TAAc application particularly during the 1st day p.i. The results may obtain a higher limit of confidence by the simultaneous demonstration of cortisol suppression. By the use of this test more detailed conclusions may be drawn about presence and duration of a pharmacodynamic action originating from the TAAc depot. (orig./TRV) [de

  18. Radioimmunoassay of parathormone in human blood serum. Radioimmunologische Bestimmung von Parathormon im menschlichen Serum. Optimierung der Methodik, pathophysiologische Aspekte und klinische Anwendung

    Energy Technology Data Exchange (ETDEWEB)

    Leicht, E.

    1982-01-01

    A radioimmunoassay for immune reactive PTH in human blood serum has been developed and optimized. The method described is capable of largely safely discriminating increased PTH concentrations from normal values. For the group of patients suffering from hypoparathyroidism, the PTH values in the blood serum have been found to be generally lower, but quite an overlapping of lower values and values at the lower normal limit has been stated at the same time. Subsequent to an oral administration of phosphate in an acute experiment, so following a calcium-deficient diet taken over 24 hours, an increase in immune reactive PTH in the serum could be detected. The part of this thesis dealing with the method of treatment thoroughly discussed the various steps of optimization of the assay on the basis of extensive experimental data collected by the author. It presents a detailed assessment of current knowledge on, efficiency of and problems involved in PTH determination by radioimmunoassay.

  19. The Effects of Omega 3 Fatty Acids Supplementation on Serum Lipid Profiles, C-Peptide and Fasting Blood Glucose in Obese Volunteers

    Directory of Open Access Journals (Sweden)

    Majid Mobasseri

    2013-12-01

    Full Text Available Background: Obese patients are at high risk of numerous chronic diseases including diabetes, hypertension, heart disease, dyslipidemia and stroke. Recently researchers focused on complementary medicine along with routine treatments to reduce obesity complications. Therefore we aimed to investigate the effects of omega 3 fatty acids supplementation on serum lipid profiles, C-peptide and fasting blood glucose in obese individuals.   Methods: In this randomized clinical trial 56 obese volunteers with the mean age of 33.94±8.15 years were assigned into the supplemented (n=30 and placebo (n=26 groups, given two omega 3 fatty acids soft gel (360 mg EPA and 240 DHA or placebo respectively for 4 weeks. At the onset and the end of the intervention, blood samples were collected after overnight fasting and serum lipid profiles, C-peptide and fasting blood glucose were measured. Data were analyzed with SPSS program and p-value less than 0.05 considered as significant.   Results: In comparison with placebo group, omega 3 supplementation resulted in a significant decrease in the mean triglyceride (108.37±11.22 mg/dl vs 148.84±59.40 mg/dl. After 4 weeks, the mean C-peptide concentrations increased in both groups but elevation in omega 3 group was more dramatic (p<0.01. However, we didn’t find any significant changes in the mean total cholesterol, LDL-C and HDL-C levels.   Conclusion: Our finding indicated that 4 weeks Omega 3 supplementation leads to amelioration in some of serum lipid profiles indices and insulin secretion in   obese individuals. Although, further studies are needed to achieve precise results.

  20. The use of diatomite microcolumns for the chromatographic separation of steroids prior to radioimmunoassay

    International Nuclear Information System (INIS)

    Abraham, G.E.

    1975-01-01

    Since most anti-steroid antibodies are not usually specific enough to permit direct radioimmunoassay of these compounds, chromatographic purification is required to achieve reliability Celite microcolumns were used for the separation of a wide range of steroids prior to radioimmunoassay. Depending on the polarity of the steroids to be separated, various mixtures of solvents are used as stationary and mobile phases. This system is rapid, easy, economical and reliable

  1. Miniaturized technique for the rapid extraction of plasma glucagon for radioimmunoassay

    International Nuclear Information System (INIS)

    Flatt, P.R.

    1981-01-01

    Radioimmunoassay of glucagon is hampered by interference from non-specific factors introduced into the incubation mixture by the plasma sample. The proteolytic destruction of glucagon must be minimized by using proteolytic enzyme inhibitors or plasma extraction techniques. The present report, which describes a miniaturized technique for the quantitative extraction of glucagon from plasma, is aimed at increasing the popularity of this approach to the plasma glucagon radioimmunoassay. (Auth.)

  2. Two-step ion-exchange chromatographic purification combined with reversed-phase chromatography to isolate C-peptide for mass spectrometric analysis.

    Science.gov (United States)

    Kabytaev, Kuanysh; Durairaj, Anita; Shin, Dmitriy; Rohlfing, Curt L; Connolly, Shawn; Little, Randie R; Stoyanov, Alexander V

    2016-02-01

    A liquid chromatography with mass spectrometry on-line platform that includes the orthogonal techniques of ion exchange and reversed phase chromatography is applied for C-peptide analysis. Additional improvement is achieved by the subsequent application of cation- and anion-exchange purification steps that allow for isolating components that have their isoelectric points in a narrow pH range before final reversed-phase mass spectrometry analysis. The utility of this approach for isolating fractions in the desired "pI window" for profiling complex mixtures is discussed. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Association between age, IL-10, IFN¿, stimulated C-peptide and disease progression in children with newly diagnosed Type 1 diabetes

    DEFF Research Database (Denmark)

    Kaas, A; Pfleger, Claudia Christina; Kharagjitsingh, A V

    2012-01-01

    Aims: The relation of disease progression and age, serum interleukin 10 (IL-10) and interferon gamma (IFN¿) and their genetic correlates were studied in paediatric patients with newly diagnosed Type 1 diabetes. Methods: Two hundred and twenty-seven patients from the Hvidoere Study Group were...... classified in four different progression groups as assessed by change in stimulated C-peptide from 1 to 6 months. CA repeat variants of the IL-10 and IFN¿ gene were genotyped and serum levels of IL-10 and IFN¿ were measured at 1, 6 and 12 months. Results: IL-10 decreased (P...

  4. Dessert formulation using sucralose and dextrin affects favorably postprandial response to glucose, insulin, and C-peptide in type 2 diabetic patients.

    Science.gov (United States)

    Argyri, Konstantina; Sotiropoulos, Alexios; Psarou, Eirini; Papazafiropoulou, Athanasia; Zampelas, Antonios; Kapsokefalou, Maria

    2013-01-01

    Dessert compositions may conform to diabetic diet when it contains low sugar or artificial sweetener to replace sugar. However, it is still questionable whether glycemic control in type 2 diabetes patients is improved by the use of diet-conforming dessert compositions. To compare, in type 2 diabetes patients, the glycemic, insulin, and C-peptide responses to seven modified dessert compositions for diabetics (D-dessert) with the response to seven similar desserts of non-modified composition, used as control desserts (C-dessert). Seventy type 2 diabetes patients were allocated to seven groups of ten. On three occasions, each patient received either the meal which consisted of bread and cheese, or the meal and D-dessert, or the meal and the respective C-dessert. Differences in postprandial glucose, insulin, and C-peptide were evaluated using analysis of repeated measures at 0, 30, 60, 90, and 120 min after consumption. D-cake and D-pastry cream resulted in lower glucose levels (8.81 ± 0.32 mmol/l and 8.67 ± 0.36 mmol/l, respectively) and D-strawberry jelly in lower insulin levels (16.46 ± 2.66 μU/ml) than the respective C-desserts (9.99 ± 0.32 mmol/l for C-cake, 9.28 ± 0.36 mmol/l for C-pastry cream, and 27.42 ± 2.66 μU/ml for C-strawberry jelly) (p pastry cream increased glucose to a lesser extent than C-pastry cream (p < 0.05). Similar effects were reported for D-milk dessert, D-millefeuille, and D-chocolate on glucose, insulin, and C-peptide at specific timepoints. D-crème caramel showed no effect. Some desserts formulated with sugar substitutes and soluble fiber may have a favorable effect on postprandial levels of glucose, insulin, and C-peptide in type 2 diabetic patients.

  5. Fasting c-peptide and insulin-like growth factor-binding protein-1 levels help to distinguish childhood type 1 and type 2 diabetes at diagnosis.

    Science.gov (United States)

    Katz, Lorraine E Levitt; Jawad, Abbas F; Ganesh, Jaya; Abraham, Máire; Murphy, Kathryn; Lipman, Terri H

    2007-04-01

    Children with new onset diabetes (n = 175) were evaluated over 12-months. Patients were presumptively diagnosed with type 2 diabetes mellitus (T2DM) (n = 26) based on obesity, a relative with T2DM, the ability to wean from insulin, and absence of glutamic acid decarboxylase-65 (GAD-65) antibodies. We hypothesized that markers of insulinization at diagnosis, including fasting C-peptide and insulin-like growth factor-binding protein (IGFBP)-1, in addition to initial CO(2) levels and urine ketones, would help in distinguishing type 1 diabetes mellitus (T1DM) from T2DM. Children with T1DM (84 male, 65 female) had a mean age of 8.7 +/- 4.3 yr and a racial background of 78% white, 19% black, and 3% other. In contrast, children with T2DM (13 female, 13 male) had a mean age of 14.2 +/- 3.1 yr with a racial background of 58% black, 27% white, and 15% other. Fasting C-peptide level was 0.38 +/- 0.37 ng/mL in T1DM vs. 2.66 +/- 2.14 ng/mL in T2DM; a C-peptide of 0.85 ng/mL had 83% sensitivity in distinguishing T1DM from T2DM. Fasting IGFBP-1 level was 38.1 +/- 39.1 ng/mL (T1DM) vs. 3.6 +/- 4.5 ng/mL (T2DM); a value of 3.6 ng/dL could distinguish the two types of diabetes with 93% sensitivity. Urinary ketones were found in 79% of children with T1DM compared with 56% of those with T2DM, and the magnitude was associated with type of diabetes. Initial CO(2) level for T1DM was 17.9 +/- 6.9 mmol/L vs. 22.7 +/- 5.7 mmol/L for T2DM; a value of 21.5 mmol/L could distinguish the two types of diabetes with 83% sensitivity. In addition to obesity, family history of T2DM, and absence of GAD-65 antibodies, children with new-onset T2DM may be distinguished from those with T1DM by a combination of biochemical parameters (C-peptide, IGFBP-1, CO(2), and urine ketones).

  6. The development and application of radioimmunoassay methods for the serodiagnosis of intrauterine and congenital virus infections

    International Nuclear Information System (INIS)

    Kangro, H.O.

    1980-01-01

    The development of indirect solid-phase radioimmunoassay (RIA) procedures for qualitative and quantitative determinations of immunoglobulin (Ig) class-specific antibodies against rubella and cytomegalovirus (CMV) is described. RIA for the detection of virus-specific IgG class antibodies was found to be on average 40-130 times more sensitive than the conventional tests and could easily be adapted to provide simple and reliable screening tests for immunity to rubella and CMV. It was shown that IgG class antibodies do not significantly interfere with virus-specific IgM class antibody determinations by RIA and therefore this technique could be used for testing serum samples without prior fractionation. The detection of rubella-specific IgM class antibody determinations by RIA was found to be a practical, sensitive and specific procedure which could provide a reliable method for the diagnosis of recent rubella infection. Results are also presented which show that RIA for rubella IgM antibodies is as specific as the conventional fractionation procedures currently used for the diagnosis of congenital rubella but much more sensitive. A preliminary evaluation of RIA for CMV-specific IgM class antibodies strongly indicated that this technique may also prove to be superior to current methods for the serodiagnosis of recent and congenital CMV infections. (author)

  7. Serum and urine analysis of the aminoterminal procollagen peptide type III by radioimmunoassay with antibody Fab fragments.

    Science.gov (United States)

    Rohde, H; Langer, I; Krieg, T; Timpl, R

    1983-09-01

    A radioimmunoassay based on antibody Fab fragments was developed for the aminoterminal peptide Col 1-3 of bovine type III procollagen. This assay does not distinguish the intact aminopropeptide Col 1-3 from its globular fragment Col 1. Parallel inhibition profiles were observed with human serum and urine allowing the simultaneous quantitative determination of intact and fragmented antigens in these samples. Most of the material has a size similar to that of fragment Col 1 indicating that the aminopropeptide is degraded under physiologic conditions. The concentration of aminopeptide in normal sera was in the range 15-63 ng/ml. Daily excretion was found to be in the range 30-110 micrograms. More than 50% of patients with alcoholic hepatitis and liver cirrhosis showed elevated serum levels of aminopropeptide by the Fab assay. Elevated concentrations were detected more frequently with an antibody radioimmunoassay which measures mainly the intact form of the aminopropeptide. It is suggested that analysis of patients material by both assays could improve their diagnostic application.

  8. Immune complex detection and complement activity in rheumatoid arthritis: a comparative study of a radioimmunoassay using monoclonal rheumatoid factor, gel diffusion techniques and C4 activity

    International Nuclear Information System (INIS)

    Halla, J.T.; Volanakis, J.E.; Hardin, J.G.; Schrohenloher, R.E.

    1978-01-01

    Paired sera and synovial fluids from 49 patients with rheumatoid arthritis and 25 with other forms of arthritis were tested for immune complexes by a radioimmunoassay using monoclonal rheumatoid factor and gel diffusion procedures with monoclonal rheumatoid factor and Clq. Synovial fluid hemolytic C4 and C4 adjusted for IgG concentration were determined in both groups of patients. Immune complexes were detected at similar high frequencies in the rheumatoid synovial fluids by precipitin formation with monoclonal rheumatoid factor (68%) and Clq (71%). In contrast, immune complexes in rheumatoid sere were detected in low frequency by precipitin reactions with monoclonal rheumatoid factor (10%) and Clq (0%). Using the monoclonal rheumatoid factor radioimmunoassay, thirty-one (63%) synovial fluids exceeded the mean non-RA binding activity by one standard deviation. Synovial fluid C4 adjusted for IgG as well as IgG alone distinguished between the two groups of patients whereas the C4 did not. The C4/IgG value showed a strong negative correlation with the monoclonal rheumatoid factor radioimmunoassay and Clq precipitin formation. (author)

  9. Quality control of radioimmunoassays and validation of beta-2-microglobulin radioimmunoassay

    International Nuclear Information System (INIS)

    Garcin-Rambaud, M.-J.

    1980-04-01

    The aim of this work was to devise a quality check procedure for radioimmunological analyses, easily applicable in all laboratories. The parameters most commonly analysed during such a test are: non-specific activity; total binding capacity; reproducibility; sensitivity; accuracy; specificity; specific activity of the labelled substance; affinity constant of the antigen towards its specific antibody. In the method proposed the calibration curve of any series of measurements is established by Rodbard's method. For the reproducibility study the use of Ekins' method, modified by Grillet and Marchand, was preferred. From the results obtained it is possible to plot the error-response relationship (ERR) and to establish the accuracy profile which gives a good idea of the sensitivity of the analysis method. For the specificity study this method matches the usual operational conditions as closely as possible. The determination is made on the following mixture: a half-volume (with respect to the usual volume) of biological liquid studied and previously analysed for cold antigen Ag 0 ; a half-volume of one of the dilutions prepared with the substance X liable to interfere during the Ag 0 determination. Any interferences between the substance X and the antigen are then plotted on a graph representing: as abscisse, the concentration of substance X; as ordinates, the difference between the measured and theoretical Ag 0 concentrations. This very simple representation shows the interference threshold of each substance X; accounting for its physiopathological concentration [fr

  10. Validation of a direct radioimmunoassay of melatonin in the blue fox

    International Nuclear Information System (INIS)

    Forsberg, M.; Madej, A.

    1987-01-01

    A direct radioimmunoassay procedure for the determination of melatonin in the blood of blue fox has been validated and applied. The assay required 50 μl of sample and standard, 100 μl of antiserum and 100 μl of ( 3 H)melatonin. After overnight incubation at 4 deg. C the antibody bound melatonin was separated from the free hormone with dextran-coated charcoal. Following centrifugation the antibody bound ( 3 H)melatonin was determined in a beta scintillation counter. The antiserum bound 30-35 % of the ( 3 H)melatonin at a final dilution of 1:36000. The non specific binding represented less than 5 % of the total radioactivity in all assays. The lowest detectable amount of melatonin was 2.6 fmol/tube, corresponding to 52.5 pmol/l. The inter-assay coefficient of variation at 178 and 510 pmol/l was 15.6 and 8.8 %, respectively. The precision profile, calculated from a 10-replicate standard curve, showed that the coefficient of variation decreased from 43 % at 84 pmol/l to 15 % at 336 pmol/l, and remainded at or below 10 % for concentrations exceeding 670 pmol/l. Plasma was collected from 2 male blue foxes at about hourly intervals during a 24 h period in September and assayed for melatonin. Maximum (421 pmol/l) and minimum (97 pmol/l) concentrations of the hormone were inversely related to light intensity. (author)

  11. Enzyme-linked immunosorbent assay and radioimmunoassay of serum pepsinogen A

    Energy Technology Data Exchange (ETDEWEB)

    Pals, G.; Meuwissen, S.G.M.; Frants, R.R.; Kostense, P.J.; Eriksson, A.W.; Raesaenen, V.

    1987-02-01

    The determination of serum pepsinogen A (=pepsinogen I) levels is of clinical importance in the study of duodenal ulcer, atrophic gastritis and gastric cancer. In the present study two different quantitative immunological techniques for serum pepsinogen A were compared: a radioimmunoassay (RIA) (Helsinki) and an enzyme-linked immunosorbent assay (ELISA) (Amsterdam). Serum samples of 177 subjects with various gastric diseases were tested in a double blind study. The correlation was excellent (r=0.954 in the range 0-760 ..mu..g/l and r=0.971 in the range 0-100 ..mu..g/l). The functional relationship between ELISA (x) and RIA (y), determined by weighted model II regression, was y=1.12x-0.54. Initially the use of goat anti-PGA in the ELISA resulted in falsely high values in about 10% of the individuals. This was caused by circulating antibodies cross-reacting with goat IgG. This artefact was eliminated by pre-incubation of all samples with non-immune goat serum.

  12. Enzyme-linked immunosorbent assay and radioimmunoassay of serum pepsinogen A

    International Nuclear Information System (INIS)

    Pals, Gerard; Meuwissen, S.G.M.; Frants, R.R.; Kostense, P.J.; Eriksson, A.W.; Raesaenen, Vesa

    1987-01-01

    The determination of serum pepsinogen A (=pepsinogen I) levels is of clinical importance in the study of duodenal ulcer, atrophic gastritis and gastric cancer. In the present study two different quantitative immunological techniques for serum pepsinogen A were compared: a radioimmunoassay (RIA) (Helsinki) and an enzyme-linked immunosorbent assay (ELISA) (Amsterdam). Serum samples of 177 subjects with various gastric diseases were tested in a double blind study. The correlation was excellent (r=0.954 in the range 0-760 μg/l and r=0.971 in the range 0-100 μg/l). The functional relationship between ELISA (x) and RIA (y), determined by weighted model II regression, was y=1.12x-0.54. Initially the use of goat anti-PGA in the ELISA resulted in falsely high values in about 10% of the individuals. This was caused by circulating antibodies cross-reacting with goat IgG. This artefact was eliminated by pre-incubation of all samples with non-immune goat serum. (author)

  13. The detection of rubella-specific IgM antibodies by radioimmunoassay

    International Nuclear Information System (INIS)

    Kangro, H.O.; Pattison, J.R.; Heath, R.B.

    1978-01-01

    An indirect solid-phase radioimmunoassay (RIA) has been developed for the detection of immunoglobulin (Ig) class-specific rubella antibodies. A commercial rubella haemagglutinin is dried and fixed on to the wells of flexible microtitre plates and allowed to react with serial dilutions of whole or fractionated human sera. Class-specific rubella antibodies are then detected by determining the specific binding of 125 I-labelled anti-human IgG or IgM. The RIA was first evaluated by comparison with the heamagglutination-inhibition (HI) test for the detection of rubella-specific IgM in gel-filtration fractions. RIA was found to be as specific as HI but 50-150 times more sensitive. Rubella-specific IgG antibodies did not interfere in specific IgM determinations by RIA and therefore the latter technique applied to unfractionated sera. The results obtained indicate that RIA on unfractionated sera is a practical, sensitive and specific technique which could provide a reliable method for the diagnosis of rubella. The rubella-specific IgM titres obtained by RIA were not increased by the removal of IgG by pretreatment of sera with Staphylococcal Protein A. (author)

  14. A new solid-phase sandwich radioimmunoassay and its application to the detection of snake venom

    International Nuclear Information System (INIS)

    Coulter, A.R.; Cox, J.C.; Sutherland, S.K.; Waddel, C.J.

    1978-01-01

    A solid-phase sandwich radioimmunoassay is described which can be used for the detection and quantitative estimation of crude snake venom and a snake neurotoxin in clinical and experimental situations. Rabbit IgG antivenom or antineurotoxin, covalently coupled to a solid phase (CH-Sepharose 4B) is incubated with sample of unknown venom concentration. Venom bound by the solid-phase antibody is detected by reaction with 125 I-labelled rabbit IgG antivenom or antineurotoxin ([ 125 I]IgG). The resultant count, T, is the total (specific and non-specific) uptake of [ 125 I]IgG. Non-specific binding N, is similarly determined, but with normal rabbit IgG antivenom or antineurotoxin ([ 125 I]IgG). The resultant count, T, is the total (specific and non-specific) uptake of [ 125 I]IgG. Non-specific binding N, is similarly determined, but with normal rabbit IgG bound to the solid phase. A T:N value greater than 1.8 for human serum or urine indicates the presence of venom in a sample (P>0.95). Positive samples are assayed at several dilutions and the venom present estimated from the specific count (T-N). Levels of 0.4 ng/ml of crude tiger snake venom (TSV) and 0.1 ng/ml of neurotoxin can be reliably detected by this procedure. (Auth.)

  15. The studies on aldosterone secretion rate by radioimmunoassay

    International Nuclear Information System (INIS)

    Takenouchi, Takahiko

    1974-01-01

    The aldosterone secretion rate was measured by radioimmunoassay in 12 normal subjects and 47 hypertensive patients. The values ranged from 25.0 to 60.2 ng/day with a mean of 39.6+-10.7 (S.D.) in 8 normal males and from 30.2 to 85.4 ng/day with a mean of 62.6+-26.8 (S.D.) in 4 normal females. The mean value in 21 cases with benign essential hypertension was found to be within normal range. No significant difference was found in the aldosterone secretion rate between the group of benign essential hypertension with suppressed renin activity and with nonsuppressed renin activity. Metabolic clearance rate in benign essential hypertension was observed to be within normal range. The aldosterone secretion rate in a few cases of benign essential hypertension failed to increase normally in response to sodium restriction (<50 mEq/day). The values in 11 cases of primary aldosteronism were found to be clearly higher, when compared with the values of normal subjects and subjects with benign essential hypertension. High values were found in patients suffering from malignant hypertension and in 3 with unilateral renal artery stenosis. The values in cases of bilateral renal artery stenosis, of pheochromocytoma, and of acromegaly with hypertension were within normal range. Low values in the aldosterone secretion rate were found in 3 cases each of 17α-hydroxylase deficiency and Cushing's syndrome. (JPN)

  16. Radioimmunoassay for progesterone in human saliva during the menstrual cycle

    Energy Technology Data Exchange (ETDEWEB)

    Luisi, M.; Franchi, F.; Kicovic, P.M.; Silvestri, D.; Cossu, G.; Catarsi, A.L.; Barletta, D.; Gasperi, M. (Pisa Univ. (Italy))

    1981-10-01

    A sensitive, specific and accurate radioimmunoassay of progesterone in human saliva is described, using /sup 3/H. The assay had a sensitivity of 8 pg/tube and blanks were negligible. The intra- and inter-assay coefficients of variation were 5.2 and 9.4%, respectively. The mean recovery from 60 samples was 93.2 +- 6.3%. Results obtained from nine healthy, normally menstruating women showed that salivary progesterone rose from the 4th day before ovulation to a mean peak (+- SD) of 1.14 +- 0.17 ng/ml on the 8th day after ovulation, followed by a gradual decline. Correlation of salivary and simultaneously obtained plasma progesterone levels was good (r = 0.47; P < 0.001), although the maximum percent increase in salivary progesterone was more than 10 times greater than that of plasma progesterone. Salivary progesterone is thought to reflect the unbound fraction of plasma progesterone and this non-invasive technique can be used for serial investigations in which frequent samplings are required.

  17. Labelling and standardizing some pituitary hormones for radioimmunoassay

    International Nuclear Information System (INIS)

    Kim, Y.S.

    1976-11-01

    Optimum conditions for efficient 125 I labelling of human follicle stimulating hormone (FSH) and human chorionic gonadotropin (HCG) using chloramine-T have been established for radioimmunoassay (RIA). The amount of the hormone, chloramine-T, 125 I, and the reaction time were, respetively, controlled evaluating the yield and the bindability of the labelled hormone to its antibody. To measure the bindability, the labelled hormone was incubated together with its antibody for a definite temperature. In the separation of the free hormone (F) from the antibody bound (B), a double antibody technique was applied comparing with the chromatoelectrophoresis. For the efficient separation of the labelled hormone, two methods of separation such as gel filtration and gel electrophoresis were compared in the sensitivity and in the immunological activity points of view. Experiments for the production of HCG antibody were also conducted. The produced antisera were tested in two ways; i.e., the incubation test with the labelled hormone, and the Ouchterlony test. Using the produced anti-HCG serum and the purchased anti-FSH serum, standard dose-response curves were plotted correlating with the international standard preparation of the hormones

  18. Radioimmunoassay for plasma corticotropin in frogs (Rana esculenta L.)

    International Nuclear Information System (INIS)

    Vaudry, H.; Vague, P.; Dupont, W.; Leboulenger, F.; Vaillant, R.

    1975-01-01

    A radioimmunoassay technique has been developed for measuring frog plasma corticotropin (ACTH) without prior extraction. Using synthetic porcine ACTH as a reference standard, 131 I-labeled synthetic human ACTH (sp act greater than 500 mCi/mg) as tracer and rabbit anti-porcine ACTH serum, the lower measurable value was estimated at about 4 pg ACTH. Only human and porcine ACTH, ACTH, and frog pituitary ACTH reacted with the rabbit anti-porcine ACTH serum. No cross-reactivity has been found with synthetic ACTH, αMSH, and bovine βMSH. Appearance of damaged 131 I-h ACTH components after storage in plasma solutions was followed for 7 days. The conditions making it possible to reduce ACTH damage have been ascertained. The average plasma corticotropin level (+- CI) was found to be 38.8 +- 7.8 pg/ml without any significant difference between males and females. These results suggest that frog ACTH secretion has much in common with mammalian secretions

  19. Radioimmunoassay of angiotensin-II: methodology and standardization.

    Science.gov (United States)

    Lall, S B; Peshin, S S; Seth, S D

    1995-12-01

    The study was planned to set up and standardize the radioimmunoassay of Ang-II and to validate the procedure in terms of precision, sensitivity, specificity and recovery. The application of the developed assay was studied in normal healthy volunteers and in patients of renovascular hypertension (RVHT) and renal hypertension (RH). Synthetic human Ang-II was coupled to BSA by carbodimide condensation to get the hapten carrier conjugate which was injected in rabbits to raise the antibodies. The titre of 1:250 showed significant binding (56.79%) and was used for the assay. The sensitivity of the assay was 2 pg/ml and cross-reactivity with analogues of Ang-II was minimum. Mean Ang-II levels in normal subjects was 16 +/- 3.6 pg/ml. In patients of RVHT and RH, the peripheral blood Ang-II levels were found to be 876 +/- 8.6 and 108 +/- 2.3 pg/ml respectively. In patients of unilateral RVHT, renal vein Ang-II levels of the affected side were significantly higher than the unaffected side (P < 0.001). The results indicate that unextracted samples can be successfully utilized to estimate Ang-II levels.

  20. An Interlaboratory study of lipid effects on steroid radioimmunoassay

    International Nuclear Information System (INIS)

    Bolelli, G.F.; Franceschetti, F.; Mimmi, P.; Malvano, R.; Pilo, A.; Zucchelli; Rota, G.

    1986-01-01

    The lipid effects on the performances of routine steroid radioimmunoassay (RIA) have been assessed using the scheme of the CNR interlaboratory quality control program. Cortisol, estradiol, progesterone and testosterone assays have been considered. In the study, ca 80 laboratories were supplied with two sets of control plasma samples with different triglyceride contents (pool N, ca 120 mg/dl; pool L, ca 310 mg/dl), each corresponding to three steroid levels (level 0: charcoaldeprived samples; levels 1 and 2: the same added with increasing steroid amounts). A comparison of the neat results obtained by partecipants for both levels 1 and 2 of N and P panels - after subtraction of the concentrations estimated for level 0 - gave a direct information on lipid effects (triglycerides being assumed as an index of lipemia). In no case the abnormality high triglyceride content proved effective in practical terms, though significant differences were observed for testosterone and progesterone (ca 10% underestimation in pool L) and for estradiol (ca 10% overestimation in pool L)

  1. Measurement of guinea pig eosinophil major basic protein by radioimmunoassay

    International Nuclear Information System (INIS)

    Wassom, D.L.; Loegering, D.A.; Gleich, G.J.

    1979-01-01

    Guinea pig eosinophil major basic protein (MBP) was measured by radioimmunoassay (RIA) using 131 I-MBP. Two critical features of the assay were: (1) alkylation of the MBP with iodoacetamide prior to radioiodination and (2) inclusion of another basic protein, either protamine or histone, in the phosphate buffer. Freshly isolated non-alkylated MBP was immunologically deficient when compared to alkylated or reduced MBP, but its reactivity could be redtores by reduction with dithiothreitol and alkylation. Reduction and alkylation also restored the immunoreactivity of polymerized MBP. MBP levels were not elevated in sera from guinea pigs parasitized with Trichinella spiralis and having peripheral blood eosinophilia. Muscle extracts from Trichinella infected animals showed significantly higher levels of MBP activity than normal controls. MBP was measurable in extracts of untreated eosinophils, but reduction and alkylation of these extracts increased MBP activity several fold. The RIA permits detection of MBP in body fluids and tissues at levels as low as 2 ng./ml. The RIA is useful in assessing increased or decreased levels of MBP activity in samples from experimental animals when compared to samples from controls. (author)

  2. Precision of radioimmunoassays by various types of data processing systems

    International Nuclear Information System (INIS)

    Ujiie, Morimichi

    1979-01-01

    The following are the result of the investigation of the precision of radioimmunoassays by various types of data processing systems presently performed in Japan. Chose 50 facilities, where 10 facilities of clinical laboratories were included. Tested 334, 485 cases per month, which corresponds to 40% of the total number of the cases treated all over the country. It was known that the data of 74% of all facilities and 94% of all tests were being processed by computing machines. In 66 times of data processing of insulin and T3 measurements, 32 were performed by the hyperbola method, 11 by the log-logit curve method of secondary degree, 9 by the logistic curve method and 8 by the log-logit curve method of first degree. Practically in more than 90% of all cases were processed by these 4 types of curve methods. In insulin measurements of many standard points (8 points), favourable results could be obtained by the logistic curve method. On the contrary, in T3 measurements of fewer standard points (5 points), the results from the method of log-logit curve of secondary degree were good. Favourable results of both insulin and T3 measurements could be obtained by the hyperbola method. While, in the insulin measurement by the method of log-logit curve of first degree, the values were a bit lower in the higher and lower concentration ranges, and 3 -- 4% higher than the actual values in the middle concentration range. (author)

  3. Specific radioimmunoassay of human. beta. -endorphin in unextracted plasma

    Energy Technology Data Exchange (ETDEWEB)

    Wiedemann, E. (Univ. of California, Berkeley); Saito, T.; Linfoot, J.A.; Li, C.H.

    1979-09-01

    With an antiserum against human ..beta..-endorphin (..beta..-EP) crossreacting <2% with human ..beta..-lipotropin (..beta..-LPH) by weight we have developed a radioimmunoassay that can detect 1 pg ..beta..-EP in diluted raw plasma. In a.m. fasting plasma of 14 normal subjects ..beta..-EP ranged from <5 to 45 pg/ml. ..beta..-EP was elevated in untreated, but normal in successfully treated Cushing's disease; undetectable in a patient with adrenal adenoma; extremely high in Nelson's syndrome; and elevated in a patient with bronchogenic carcinoma before, but undetectable after tumor resection. In subjects with intact hypothalamic-pituitary-adrenal axis, ..beta..-EP was undectectable after dexamethasone and increased after metyrapone administration and insulin-induced hypoglycemia. ..beta..-EP concentration was considerably lower in serum than in simultaneously collected plasma, but increased in serum left unfrozen for several hours after clot removal. Thus, ..beta..-EP behaves like a hormone responding to the same stimuli as ACTH and ..beta..-LPH and blood appears to contain enzymes both generating and destroying immunoreactive ..beta..-EP.

  4. Solid phase radioimmunoassays for human C-reactive protein

    International Nuclear Information System (INIS)

    Shine, B.; Beer, F.C. de; Pepys, M.B.

    1981-01-01

    Two new, rapid and sensitive radioimmunoassays for human C-reactive protein (CRP) have been established using antiserum coupled to magnetizable cellulose particles, which facilitate phase separation. A single antibody method, using solid phase anti-CRP, provides a sensitivity of 50 μg/l with a 1-h incubation time and intra- and inter-assay coefficients of variation of 10%. A double antibody method, using fluid phase rabbit anti-CRP serum and solid phase sheep anti-rabbit IgG serum, provides a sensitivity of 3 μg/l with an overnight incubation and intra- and inter-assay coefficients of variation of 10%. Among 468 sera from normal adult volunteer blood donors the median CRP concentration was 800 μg/l, interquartile range 340-1700 μg/l and range 70-29,000 μg/l. Ninety percent of samples contained less than 3 mg/l and 99% less than 10 mg/l. Low levels (14-650 μg/l) of CRP were detected both in amniotic fluids and in cerebrospinal fluids. (Auth.)

  5. Detection of myocardial infarct extension by CK-B radioimmunoassay

    International Nuclear Information System (INIS)

    Rothkopf, M.; Boerner, J.; Stone, M.J.; Smitherman, T.C.; Buja, L.M.; Parkey, R.W.; Willerson, J.T.

    1979-01-01

    Myocardial infarct extension after the acute event was defined as a second rise in the myocardial isoenzyme of serum creatine kinase (CK-B) after the initial return of CK-B to normal values. In 43 patients with acute myocardial infarct, CK-B was measured by radioimmunoassay every 12 hrs for 14 days. Nineteen patients had anterior transmural myocardial infarcts (AMI), 14 had inferior transmural myocardial infarcts (IMI), and 10 had subendocardial myocardial infarcts (SEMI). Infarct extension as detected by a second rise in serum CK-B occurred in six patients (32%) with AMI, two (14%) with IMI, and two (20%) with SEMI. Four patients with AMI also had clinically evident infarct extension. In the other six, the infarct extension was undetected clinically. The measurement of serum CK-B values with a quantitative and sensitive assay suggests that myocardial infarct extension occurs more commonly than clinically recognized, but the frequency of extension may be less than that reported in patients in whom precordial mapping and total serum CK values were measured to identify this phenomenon

  6. Laboratory training manual on radioimmunoassay in animal reproduction

    International Nuclear Information System (INIS)

    1984-01-01

    Reproduction must always be regarded as one of the major limiting factors in animal production and many of the modern methods for improving reproduction rely heavily on the ability to measure hormone levels in blood and milk. This has produced a world-wide demand for laboratory facilities to carry out hormone assays and the need for specialist training to allow these assays to be undertaken. The need to measure nanogram and picogram quantities and the use of radionuclides require a good deal of skill and care and this Manual has been prepared to aid training and provide the sort of information that rarely appears in scientific papers. It represents a further step in the Joint FAO/IAEA Division's series of Laboratory Training Manuals, and has been designed to aid training programmes of the type carried out during the Joint FAO/IAEA Interregional Training Course on Radioimmunoassay and its Application in Research on Animal Reproduction at Cornell University in July 1982. Many of the laboratory exercises described in this Manual are based on those conducted during the course

  7. An Evaluation by TSH Radioimmunoassay on Familial Thyroid Disorders

    International Nuclear Information System (INIS)

    Kim, Ji Yeul

    1989-01-01

    The occurrence of thyroid disorders is connected with iodine deficiency, defective synthesis or releasing of thyroid hormone and endemicity. Genetic factors are known as a single gene defects, interaction of multiple genes with environmental factors, as well as chromosomal aberrations. Diofnosis thyroid disorders is enforced by 13I uptake test, thyroid scanning with 131 I or 99m Tc and serum radioimmunoassays of T3, T4, free T4 and TSH. They were largely classified as hypothyroidism, hyperthyroidism, simple goiter and normal. The pedigree of 58 families was drawn by propositus, and then the correlation between thyroid disorders and TSH levels was analyzed. The results are as follows: 1) The offsprings and their mothers of 15 families were hypothyroidism, THS level was 5 folds for offsprings and 4 folds for mothers in comparison with control group. 2) 13 families were hyperthyroidism in siblings but their mothers were normal in thyroid function, TSH level of the siblings was lower than control group. 3) Though the offsprings and their mothers of 10 families were similar to TSH level of control group, they are all simple goiter, familial thyroid disorders, in other thyroid function test. The familial thyroid disorders suggested that these transmitted from mothers to offsprings with X-linked dominant or autosomal dominant inheritance.

  8. Radioimmunoassay of steroids in homogenates and subcellular fractions of testicular tissue

    International Nuclear Information System (INIS)

    Campo, S.; Nicolau, G.; Pellizari, E.; Rivarola, M.A.

    1977-01-01

    Radioimmunoassays for testosterone (T), dihydrotestosterone (DHT) and 5alpha-androstan-3alpha, 17beta-diol (DIOL) in homogenates of whole testis, interstitial tissue and seminiferous tubules as well as subcellular fractions of the latter were developed. Steroids were extracted with acetone, submitted to several solvent partitions and isolated by a celite: propylene glycol: ethylene glycol column chromatography. Anit-T serum was used for the assay of T and DTH, and a specific anti-Diol serum for DIOL. Subcellular fractions were separated by differential centrifugation. The nuclear fraction was purified by centrifugation in a dense sucrose buffer followed by several washings. Losses were corrected according to recovery of DNA. Optimal conditions for purification of acetone extracts at minimal losses were established. Validation of the method was studied testing linear regression of logit-log transformations of standard curves and parallelism with unknowns. T was the steroid present in higher concentrations in all samples studied. It is concluded that the present method for determination of endogenous androgen concentrations in testicular tissue is valid and might be useful in studing testicular function. (orig.) [de

  9. Insulin radioimmunoassay kit (125I) using polyethyleneglycol (PEG) and a double antibody separation method

    International Nuclear Information System (INIS)

    Borza, Virginia; Chariton, Delfina; Neacsu, Elena

    1997-01-01

    Insulin is a polypeptide hormone formed from proinsulin in the b-cells of the islets of Langerhans in the pancreas. It has a widespread effect on carbohydrate, lipid and protein metabolism. Diabetes mellitus is the result of an insulin deficiency brought about either by insufficient insulin secretion or by rapid insulin catabolism. The determination of the insulin level is important for differential etiologic diagnosis and subsequent therapy and prognosis. Insulin radioimmunoassay kit provides a sensitive, precise and specific assay for insulin concentration in serum. Standard and insulin in the patient sample compete with tracer for binding sites on an insulin antibody. The antigen-antibody combination, which forms during incubation time, will be separated from free insulin by different methods. The separation technique using the double antibody technique combined with Polyethyleneglycol (PEG) is presented. The results are compared with the separation method using PEG alone and with double antibody technique. Antiserum to insulin was produced in rats immunized with porcine insulin, while rabbits immunized with rat-g globulin were used as a source for the second antibody.The tested PEG was PEG 6000. The best results were obtained using the double antibody at a 1/50 dilution combined with 7.5 PEG solutions. The time for precipitating the antibody bound fraction by this technique was established to be 30 minutes. The results obtained using this method as separation technique for insulin - antibody complex were better than those obtained using the double antibody techniques or PEG as precipitating agent alone. (authors)

  10. Localization by immunoperoxidase and estimation by radioimmunoassay of carcinoembryonic antigen on colonic polyp

    International Nuclear Information System (INIS)

    Sharkey, R.M.; Hagihara, P.F.; Goldenberg, D.M.

    1977-01-01

    A 3-layer immunoperoxidase technique was used to demonstrate carcinoembryonic antigen (CEA) in colonic polyps from patients with or without previous or concurrent malignancy. CEA was demonstrated in a higher percentage of the polyps received as fresh specimens that were rapidly frozen and fixed in ethanol, than in formalin-fixed, paraffin-embedded sections. Tissue CEA content of both colonic carcinomas and polyps was determined by radioimmunoassay, and it was found that benign colonic tumours had levels of tissue CEA comparable to colonic cancer, indicating that CEA concentration in a tumour does not reflect its grade of malignancy. In fact, in one case in which both colonic cancer and polyps were removed, the polyps has the higher quantities of tissue CEA. Further, tissue CEA concentration of a polyp was not dependent on its size or location. Studying the titres of circulating CEA in these patients revealed an elevation of plasma CEA in one-third of the patients with only colonic polyps, whilst the patients with cancer all had increased titres. (author)

  11. Quantitative human chorionic gonadotropin analysis. I. Comparison of an immunoradiometric assay and a radioimmunoassay

    International Nuclear Information System (INIS)

    Shapiro, A.I.; Wu, T.F.; Ballon, S.C.; Lamb, E.J.

    1984-01-01

    An immunoradiometric assay (IRMA) for the quantitative analysis of human chorionic gonadotropin (hCG) was evaluated for specificity, sensitivity, accuracy and precision. The results were compared with those of the conventional radioimmunoassay (RIA) used in our laboratory. The IRMA is a solid-phase, double-antibody immunoassay that sandwiches the intact hCG molecule between the two antibodies. It has specificity, accuracy, and precision which are similar to those of the RIA. The RIA is based upon the assumptions that the antigenicity of the tracer is not altered by the iodination process and that the antibody reacts equally with all of the antigens, including the radiolabeled antigen. The IRMA does not use radiolabeled antigens and thus is free of the assumptions made in the conventional RIA. The IRMA may be more accurate at the lower limits of the assay because it does not require logarithmic transformations. Since the IRMA does not measure the free beta-subunit of hCG, it cannot be endorsed as the sole technique to quantitate hCG in patients with gestational trophoblastic neoplasia until the significance of the free beta-subunit in these patients is determined

  12. Basic studies on the radioimmunoassay of serum carcinoembryonic antigen and its clinical application

    International Nuclear Information System (INIS)

    Araki, Akio

    1976-01-01

    A two antibody system for radioimmunoassay of carcinoembryonic antigen (CEA) was established, and the specificity of the method was verified with respect to two non-specific cross-reacting antigens (NCA and NCA-2) of von Kleist and Hirsch-Marie. Diagnostic significance was evaluated by determining serum CEA levels in neoplastic and non-neoplastic diseases. In 66% of the patients with colo-rectal cancer, 40% of those with gastric cancer and 47 to 69% of those with cancers of the pancreas, liver and the lung, abnormal increases of CEA were found. In a few patients with atrophic gastritis and miscellaneous liver diseases, slightly elevated values were observed. Significantly higher levels of serum CEA were found in stage III and IV of gastric cancer, and a remarkable increase of the levels was noted in patients with liver metastasis. CEA increase was well correlated with the grade of anemia, with serum haptoglobin concentration, and with the grade of immunologic functions in patients with gastric cancer. In patients who responded well to chemotherapy and/or surgical treatment, serum CEA levels were definitely decreased, while in the majority of patients whose diseases state had progressed, the levels were clearly increased. The serum CEA level may not be useful for the early detection of cancer, but may be useful for monitoring cancer patients, especially for the evaluation of treatment and for conjecturing metastasis in the liver. With respect to its molecular size and isoelectric point the immunoreactive CEA examined in cancer sera was heterogenous. (Evans, J.)

  13. Mechanized sephadex LH-20 multiple column chromatography as a prerequisite to automated multi-steroid radioimmunoassays

    International Nuclear Information System (INIS)

    Sippell, W.G.; Bidlingmaier, F.; Knorr, D.

    1977-01-01

    In order to establish a procedure for the simultaneous determination of all major corticosteroid hormones and their immediate biological precursors in the same plasma sample, two different mechanized methods for the simultaneous isolation of aldosterone (A), corticosterone (B), 11-deoxycorticosterone (DOC), progesterone (P), 17-hydroxyprogesterone (17-OHP), 11-deoxycorticol (S), cortisol (F), and cortisone (E) from the methylene chloride extracts of 0.1 to 2.0 ml plasma samples have been developed. In both methods, eluate fractions of each of the isolated steroids are automatically pooled and collected from all parallel columns by one programmable linear fraction collector. Due to the high reproducibility of the elution patterns both between different parallel columns and between 30 to 40 consecutive elutions, mean recoveries of tritiated steroids including extraction are 60 to 84% after a single elution and still over 50% after an additional chromatography on 40cm LH-20 colums, with coefficients of variation below 15%. Thus, the eight steroids can be completely isolated from each of ten plasma extracts within 3 to 4 hours, yielding 80 samples readily prepared for subsequent quantitation by radioimmunoassay. (orig./AJ) [de

  14. Antibody binding constants from Farr test and other radioimmunoassays. A theoretical and experimental analysis

    International Nuclear Information System (INIS)

    Engel, J.; Schalch, W.

    1980-01-01

    For the reaction of monovalently reacting antibody (116-700pIEF) with its antigen (streptococcal group A-variant polysaccharide), an apparent binding constant Ksub(a) was derived by the ammonium sulfate precipitation technique (Farr assay) which was 40 times larger than the true binding constant K = 10 6 M -1 determined by fluorescence titration and equilibrium dialysis. For monovalently reacting antibodies the time needed for re-equilibration of the binding reaction is short as compared to the time of ammonium sulfate incubation. A thermodynamic analysis was therefore performed for the case of complete equilibration of all components in solution and in the ammonium sulfate precipitate. It was found that in this limiting case Ksub(a)/K is equal to the ratio of the solubilities of the antibody and the antibody complex corrected by the activity coefficients of the components in the precipitate. For other antibody-antigen reactions in which the antibody reacts with both binding sites to the same antigen molecule, re-equilibration of the binding reaction in solution is much slower. For such systems a disturbance of the binding reaction by the precipitation is less likely and correct binding constants may be obtained by the Farr technique or other radioimmunoassays involving precipitation. (author)

  15. Characterization of tumour virus proteins. I. radioimmunoassay of the P27 protein of avian viruses

    International Nuclear Information System (INIS)

    Higuchi, T.

    1977-01-01

    The major structural protein of avian oncornaviruses, a core component of about 27000 daltons, has been measured by radioimmunoassay. The purified protein was labelled with 125 Iodine by chloramine-T method. The immune serum titer was defined as the highest serum dilution able to precipitate 50% of the labelled antigon present in the system. Standard competition curve was constructed in order to determine the equivalents of protein, in a system with limiting antibody concentration. In the experimental conditions used, 0.14 ng of AMV-P27 inhibited 50% of 125 I-AMV-P27 (1.0 ng) precipitation. The 125 I-AMV-P27 vs anti-AMV-P27 system was used to study the competition of normal cells, purified virus suspension, productive cells and supernatant fluids. Most of the chicken ombryo fibroblast showed expression of this viral component. The phenomena of cell transformation, the increase in total protein, and the expression of P27 were studied in rapid transformation of CEF by RSV-SR sub(A) [pt

  16. Radioimmunoassay of extracted glucagon compared with three non-extraction assays

    International Nuclear Information System (INIS)

    Schenck, H. von; Nilsson, O.R.

    1981-01-01

    Radioimmunoassay of glucagon was performed with three different antisera, i.e. E7, 30K and 4305, all directed against the carboxyl-terminal region of glucagon and thus avoiding co-determination of glucagon-like polypeptides from the gut. Plasma samples from five healthy people subjected to various A-cell stimulation and suppression tests were used and immunoreactive glucagon assessed with the three antisera. Aliquots from all plasma samples were also extracted with acetone and glucagon re-assessed with antiserum E7. Even though all four baseline glucagon concentrations obtained were different, the glucagon profiles were comparable after superimposing the baselines. The differences in baseline concentrations of immunoreactive glucagon seem due to the interference of 'big plasma glucagon', a still unidentified factor in the E7 and 30K assays that can be precipitated by acetone. Since acetone extraction yielded the lowest baselines without altering the glucagon profiles, it is suggsted that the baseline glucagon concentrations of acetone-extracted plasma reflect the physiological level of the biologically active hormone. Using antiserum E7, our own antiserum, the normal range of glucagon values in acetone-extracted plasma samples from 22 healthy, fasting people of both sexes was 42+-16 ng/l (mean +- 2 S.D.). These values agree well with those obtained by other assay techniques. (Auth.)

  17. Radioimmunoassay of vasoactive intestinal polypeptide (VIP) in plasma. [/sup 125/I tracer techniques

    Energy Technology Data Exchange (ETDEWEB)

    Fahrenkrug, J.; Schaffalitzky de Muckadell, O.B.

    1977-06-01

    A sensitive and specific radioimmunoassay for vasoactive intestinal polypeptide (VIP) has been developed, which can detect 3.3 pmol x L/sup -1/ of the peptide in plasma. Antisera to highly purified porcine VIP coupled to albumin were raised in eight rabbits. The final dilution, the avidity, and the specificity of each antiserum were determined. /sup 125/I-VIP served as label, and highly purified porcine VIP was used as standard. Separation of antibody-bound and free VIP was achieved by plasma-coated charcoal. Nonspecific interference with the assay system was excluded by extraction of plasm samples with ethanol. The reliability of the assay was investigated by recovery experiments, by serial dilution of plasma samples with high concentration of endogenous VIP, and by immunosorption. The within-and between assay reproducibility at a concentration of 18.3 pmol x L/sup -1/ was 1.6 and 2.3 pmol x L/sup -1/ (1 S.D.), respectively. Median fasting concentration of VIP in plasma from 74 normal subjects was 7.3 pmol x L/sup -1/ (range: 0 to 20.0 pmol x L/sup -1/).

  18. Studies on radioimmunoassay diagnosis of cow pregnancy at an early period by milk sample communication

    International Nuclear Information System (INIS)

    Wu Meiwen

    1986-01-01

    Cow pregancy was diagnosed at an early period by milk sample communication and radioimmunoassay (RIA). Liquid milk samples were converted into solid forms on filter paper and mailed to the laboratory from appointed locations, and concentrations of progesterone in milk samples were then determined by RIA method. Milks were sampled 19 and 23 days after mating. Criterion used for the judgement of cow pregnancy was as follows: When the progesterone content in milk was 5 ng/ml or less, the cow was not pregnant; when progesterone content was between 5-11 ng/ml, it was doubtful; when progesterone content was 11 ng/ml or more, it was pregnant. According to this criterion, among 215 cows, 131 were pregnant, 73 were not pregnant, and 11 were doubtful. The results were further checked by palpation 3 months after inseminations. The unpregnancy and pregnancy accuracies were 97.6% and 89.2%, respectively. Forther milk samples were collected on 44 days for above cows that had been diagnosed on 19 and 23 days showing pregnancy to diagnose embryo forming. Among 91 cows, 74 had embryo. 7 had none, and the other 10 were doubtful. The embryo and unembryo accuracies were 94.6% and 100% respectively checking by palpation 3 months after inseminations

  19. Enzymatic tracer damage during the gonadotropin releasing hormone radioimmunoassay: analytical and immunological assessment

    International Nuclear Information System (INIS)

    O'Conner, J.L.; Lapp, C.A.; Clary, A.R.

    1985-01-01

    Hypothalamic supernatants from 60 day female rats were fractionated from Sephadex G-200 columns. The radioimmunoassay (RIA) for gonadotropin releasing hormone (GnRH) detected an apparently cross-reacting high molecular weight substance. The substance caused apparent displacement of iodinated GnRH binding in dose response fashion; however, no biological activity was observed in pituitary cell cultures. In order to determine whether the depressed binding might be caused by enzymatic degradation of iodinated GnRH during the RIA incubation, iodinated GnRH was preincubated under RIA conditions with either buffer or increasing concentrations of the GnRH cross-reacting material. Aliquots were subjected to polyacrylamide gel electrophoresis (PAGE) and the gels slices counted. Identical aliquots were subsequently used as iodinated hormone in the RIA of known quantities of synthetic GnRH. Tracer damage during the RIA-like preincubation period was reflected in the subsequent PAGE studies as decreased counts per minute in the intact GnRH peak and in the RIA studies as over-estimated quantification of the GnRH standards. This report describes such damage during the GnRH RIA and the data misinterpretations which result. 30 references, 6 figures, 1 table

  20. Correlative study of radioreceptor assay and radioimmunoassay of serum growth hormone (GH)

    International Nuclear Information System (INIS)

    Igarashi, Noboru; Minami, Satoshi; Kajiwara, Sohei; Sato, Tamotsu

    1987-01-01

    The radioreceptor assay (RRA) of human growth hormone (hGH) was developed using liver microsomal fraction from estrogen-treated female rats. The method allows measurement of physiological amounts of hGH (1.5 - 100 ng/ml) in unfractionated serum. Cross-reactivity with human prolactin was 4.6 %. Native hGH, recombinant methionyl-hGH, and methionine-free hGH showed a similiar binding to the receptors. Simultaneous determinations of serum hGH concentration with the RRA and radioimmunoassay (RIA) were performed in samples after the administration of GH-releasing hormone (GRH) (1 - 44) from 15 normal short children and 25 patients with hGH deficiency. Overall RRA/RIA ratio in 146 samples was 0.84 ± 0.31 (SD). Of 15 normal short children, one showed a significantly reduced RRA/RIA ratio of 0.13 ± 0.03 in comparison with that of the other (0.70 ± 0.40) (p < 0.001). His growth rate was accelerated by exogenous hGH administration, indicating that he secreted a biologically inactive hGH. The present RRA provides a useful method for screening bioinactive hGH in a large number of serum samples from children with short stature. (author)

  1. Diagnostic evaluation of serum FSH and LH in primary amenorrhea by radioimmunoassay

    International Nuclear Information System (INIS)

    Hong, I.S.; Kim, G.E.; Yoo, H.S.; Lee, J.T.; Park, C.Y.

    1980-01-01

    The usefulness of single, random measurements of serum FSH and LH in the diagnosis of primary amenorrhea by radioimmunoassay was investigated. The 16 patients were divided into 3 groups by the level of serum FSH and LH. The first group with increased level of serum FSH and LH is five patients, all of these are related to the acquired or congenital abnormality of the ovary. Further studies indicated include buccal smear, chromosome analysis, gynecography and laparoscopy. The second group with normal serum FSH and LH is nine patients, four patients of these are related to the developmental anomaly of the Mullerian duct and five patients are undetermined origin. Further studies indicated include laparoscopy and gynecography. The third group with decreased serum FSH and normal or decreased serum LH is two patients, one of these is related to the pituitary function, isolated FSH deficiency, the other is undetermined origin. Further studies indicated include the pituitary function test, LH-RH stimulation test, skull radiography. Determination of serum FSH and LH levels does not permit a specific etiologic diagnosis of promary amenorrhea. However the serum levels of FSH and LH can be used to differentiate the principal area of the investigation and can be of assistance in choosing more specific testing procedures. (Author)

  2. Quantitative autoradiography of TRH receptors and radioimmunoassay of TRH in the cat central nervous system

    International Nuclear Information System (INIS)

    Bogin, R.M.; Kreider, M.S.; Caine, S.B.; Pack, A.I.; Winokur, A.

    1986-01-01

    In the cat, microinjection of Thyrotropin-Releasing Hormone (TRH) into certain areas of the central nervous system (CNS) changes ventilation and cardiovascular variables. To initiate a more systematic investigation of these effects, they undertook a study to determine the location of TRH and its receptors in the cat CNS. Using techniques previously described from the laboratory, quantitative autoradiograms for TRH receptors of the cat brain were produced; additional specimens were dissected, and radioimmunoassay for TRH was performed. Heterogeneous distribution of receptors was observed in the cat brain. In the forebrain, large quantities of TRH receptors were found in amygdala, hippocampus, claustrum, pyriform nucleus, and tuberculum olfactorium. In the brainstem, high concentrations were localized to the dorsal motor nucleus of the vagus, the hypoglossal nucleus, and the periaqueductal grey. The cerebellum contained few receptors. The largest quantities of the TRH tripeptide were noted in the hypothalamus and septum, with substantial amounts also obtained from the olfactory bulb, corpus striatum, and thalamus. The results demonstrate that the distribution of TRH and TRH receptors in the cat brain is very similar to that previously described in the rat and human brain. They provide a basis for exploring the physiological and pharmacological effects of TRH in cats

  3. Specificity of direct radioimmunoassays of unconjugated estrone and estradiol-17β in plasma

    International Nuclear Information System (INIS)

    Grenier, J.; Strauss, N.; Scholler, R.

    1977-01-01

    Procedures for radioimmunoassay of estrone and estradiol-17β in plasma, which do not include a chromatographic step or even plasma extractions are now described in the literature and are recommended in most commercially available kits. Besides leading often to a systematic overestimation of estrogen concentrations, such techniques are liable to give results which are volume-dependent. Since this defect might be due to the type of antiserum used or the mode of separation of free and antibodybound steroid, the influence of plasma volume was studied, either with a modification of Castanier and Scholler method - i.e. suppression of Sephadex LH-20 chromatography -, using antisera of different types, or with estrogen kits. The separation step was a toluene extraction in the modified method, and dextran-coated charcoal or polyethylene glycol in procedures of commercial kits. The volume effect was always found, with varying degrees, according to the plasma sample. It was most marked in plasmas of hyperlipidemic patients. The addition of fatty acids, at an upper physiological dose, led to a modification of the standard curve, with over-estimation at low levels and under-estimation at high levels, resulting in calculated estrogen concentrations depending on volume. The use of highly specific antiserum as determined by cross-reaction studies with authentic steroids does not necessarily imply the possibility of performing direct assays which ought to pass the test of plasma volume effect before being accepted. (orig.) [de

  4. Radioimmunoassay of serum antibodies with B-streptococcus specificity in pregnant women and infants

    International Nuclear Information System (INIS)

    Frey, C.W.

    1980-01-01

    In a specific competitive radioimmunoassay of purified rabbit antibodies, labeled with iodine 125 against group- and type-antigens of streptococcus agalactiae (streptococci type B), we investigated the amount of serum anti-bodies providing specificity of streptococci type B in not preselected pregnant women, newborn and babies with colonies of streptococci type B or with diseases due to streptococci type B and in some of their mothers. These antibodies could be detected in 26 of 45 pregnant women and in 3 of 7 children with colonies of streptococci type B. 5 of 18 newborn with the ''early-onset'' type of infection and 6 of 7 of their mothers provided antibodies with specificity of streptococci type B as did one of two newborn with the ''late onset'' type of infection. Contrary to the supposition of Baker and Kasper and in accordance with the findings of Wilkinson, the ''risk group'' cannot be determined only by detecting the antibodies against streptococci type B. The risk group comprises those persons in whom the colonisation of streptococci agalactiae leads to the frequently life-threatening infecton of neonatals with streptococci type B. (orig.) [de

  5. Development of an in-house radioimmunoassay for human growth hormone.

    Science.gov (United States)

    Wan Nazaimoon, W M; Satgunasingam, N; Khalid, B

    1990-06-01

    A simple and sensitive double-antibody radioimmunoassay for human growth hormone (HGH) was developed, optimised and validated. The anti-hGH sera raised in 2 rabbits were highly specific with low cross-reactions of 0.19% and 0.3% with human placental lactogen and 0.21% and 0.13% with human prolactin. The mean sensitivity of the assay determined from 28 assays was found to be 0.4 +/- 0.2 mIU/L. Mean recovery of added exogenous hGH was 98.8 +/- 6.8%. Linearity studies of samples diluted at 1:2, 1:4 and 1:8 gave values of 101.3 +/- 5.3%, 109.6 +/- 13.4% and 97.3 +/- 13% respectively of those expected. The reproducibility of the assay was good; within assay coefficient of variation for serum samples with GH concentrations of 2.7, 13.6 and 28.2 mU/l ranged from 5.1 to 8.3% while the inter-assay precision varied from 4.9 to 10.3%. The in-house assay showed good correlation (r = 0.96, p less than 0.001) with a commercial HGH RIA kit (Dainabot, Japan). A reference normal adult fasting GH level of less than 7 mIU/l was established from 95 samples assayed by this method.

  6. Skim Milk, Whey, and Casein Increase Body Weight and Whey and Casein Increase the Plasma C-Peptide Concentration in Overweight Adolescents12

    DEFF Research Database (Denmark)

    Arnberg, Karina; Mølgaard, Christian; Michaelsen, Kim Fleischer

    2012-01-01

    In adults, dietary protein seems to induce weight loss and dairy proteins may be insulinotropic. However, the effect of milk proteins in adolescents is unclear. The objective was to test whether milk and milk proteins reduce body weight, waist circumference, homeostatic model assessment, plasma...... insulin, and insulin secretion estimated as the plasma C-peptide concentration in overweight adolescents. Overweight adolescents (n = 203) aged 12–15 y with a BMI of 25.4 ± 2.3 kg/m2 (mean ± SD) were randomized to 1 L/d of skim milk, whey, casein, or water for 12 wk. All milk drinks contained 35 g protein....../L. Before randomization, a subgroup of adolescents (n = 32) was studied for 12 wk before the intervention began as a pretest control group. The effects of the milk-based test drinks were compared with baseline (wk 0), the water group, and the pretest control group. Diet and physical activity were registered...

  7. Quantification of the adrenal cortex hormones with radioimmunoassay

    Energy Technology Data Exchange (ETDEWEB)

    Badillo A, V.; Carrera D, A. A.; Ibarra M, C. M., E-mail: vbadillocren@hotmail.co [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Calle Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

    2010-10-15

    The pathologies of the adrenal cortex -adrenal insufficiency and Cushing syndrome- have their origin on the deficit or hypersecretion of some of the hormones that are secreted by the adrenal cortex, which is divided in three zones anatomically defined: the external zone, also called the zona glomerulosa, which is the main production site of aldosterone and mineralocorticoids; the internal zone, or zona reticularis, that produces androgens; and the external zone, or zone 1 orticotrop, which is responsible for producing glucocorticoids. In this work, a quantitative analysis of those hormones and their pathologic trigger was made; the quantification was made in the laboratory by means of highly sensitive and specific techniques, in this case, the radioimmunoassay, in which a radioisotope I-125 is used. This technique is based on the biochemical bond-type reaction, because it requires of a substance called the linker, which bonds to another called ligand. This reaction is also known as antigen-antibody (Ag-Ab), where the results of the reaction will depend on the quantity of antigen in the sample and on its affinity for the antibody. In this work, a 56 patients (of which 13 were men and 43 women) study was made. The cortisol, the ACTH, the androsterone and the DHEA values were very elevated in the majority of the cases corresponding to women, predominating cortisol; while in men, a notorious elevation of the 17 {alpha}-OH-PRG and of the DHEA-SO{sub 4} was observed. Based on that, we can conclude that 51 of them did not have mayor complications, because they just went to the laboratory once, while the remaining 5 had a medical monitoring, and they visited the laboratory more than one occasion, tell about a difficulty on their improvement. According to the results, an approximate relation of 8:2 women:men, respectively, becomes clear to the hormonal pathologies of the adrenal cortex. (Author)

  8. The reproductive performance in female Damascus goats using progesterone radioimmunoassay

    International Nuclear Information System (INIS)

    Zarkawi, M.; Al-Masri, M. R.

    1998-12-01

    An experiment was conducted on Damascus goats' female kids and does to study the reproductive performance by identifying some reproductive parameters such as age and weight at puberty, start of the breeding season, duration of pregnancy and other related parameters. The above objectives were met by means of the measurement of progesterone levels in blood sera using radioimmunoassay. The results could be summarized as follows: 1- Average weight of female kids at age of 7-8 months was 30.2 kg, at puberty was 35.6 ky and at mating was 41.6 kg. 2- There were individual differences in the age at puberty ranging from 266 to 653 days. 3- At age of 7-8 months, progesterone level was 0 n mol/1 in 8, and 0.1 and 0.2 n mol/1 in the 2 remaining female kids. This level increased to an average of 6.81 n mol/1 at puberty. 4- Average duration of pregnancy was 149.0 days, overall kids' birth weight was 3.73 kg, for singles was 4.43 kg, whereas for twins was 3.21 kg, for the kids produced by the female kids. Average kids' birth weight produced by the does was: overall 4.63 kg, singles 4.02 kg and for twins was. 4.18 kg. 5- Average progesterone e level on day 21 post-mating was 23.02 n mol/1. Therefore, the accuracy of early pregnancy diagnosis was 100%. 6- The breeding season for the experimental does started in September. (author)

  9. Development of a Radioimmunoassay for Bovine Chymosin B

    Directory of Open Access Journals (Sweden)

    Borceux, JP.

    2007-01-01

    Full Text Available The present study was conducted to develop and validate a specific radioimmunoassay system for measurement of bovine chymosin B (bChyB concentrations in plasma samples. Bovine ChyB was used for immunization of rabbits and as standard and tracer. Chymosin B concentrations were measured in plasma samples from two groups of calves (Group 1: calves sampled from birth to 24 hours; Group 2: calves sampled from Day 1 to 21 after birth and from one cow during the peri-partum period. Detection limit of the assay was 9.0 ng/ml. Recovery was higher than 89.3%. Repeatability and reproducibility ranged from 1.52% to 5.23% and from 1.52% to 12.57% respectively. No cross-reaction was found with pepsinogen A from bovine, porcine or human origins. In Group 1, bChyB concentrations increased from 47.3 ± 45.1 ng/ml (5 min after birth to 325.5 ± 161.2 ng/ml (12 hours after birth, then no significant change was observed till 24 hours after birth (293.0 ± 161.5 ng/ml. In Group 2, concentrations decreased from Day 1 (455.3 ± 191.1 ng/ml to Day 21 (117.9 ± 85.1 ng/ml. In adult cow, mean concentration was 136.0 ± 32.3 ng/ml. In conclusion, bChyB is able to cross the stomach basal membrane and to reach the blood circulation at detectable levels in both young calves and adult cows.

  10. Development of reagents for radioimmunoassay of: triiodothyronine, thyroxine and thyrotrophin

    International Nuclear Information System (INIS)

    Delgado S, B.; Lavalley E, C.; Ruiz J, A.; Garcia F, C.; Zamorano A, F.

    1991-12-01

    The radioimmunoassay (RIA) of thyroid hormones it is the but it frequents of all the studies carried out by RIA in the laboratories of Nuclear Medicine, these essays are carried out with imported reagents. In the ININ the reagents and the necessary methodology have been developed for the triiodothyronine (T3), thyroxine (T4) and thyrotrophin (TSH). The good titles of the antibodies (Ac) primary for each hormone were of 1:4,000; 1:750 and 1:1,500. The used separation system was of double Ac with PEG to 10%, with titles of 1:10 for the second Ac of lamb. The specific activity for 125-I-T3 and 125-I-T4 oscillate between 850 at 900 μCi / μ g: being this of 90 μ Ci /μg for TSH. To the first two hormones they were added 1-8 aniline naftalen sulfonic acid (ANS) to concentrations of 3 and 2 mg/ml respectively. As buffer for T3 and T4 it was used Tris-HCl pH 8.6 and PBS with normal serum of rabbit (SNC) for TSH. The standards got ready in buffer or free serum of thyroid hormones. The slope of the standard curves varied between -2.3 to -2.7 and the variation intra and inter assay among 4 to 10%. It is had at the moment in the ININ with standardized reagents for the RIA of T3, T4 and TSH, it is hoped to carry out tests in other laboratories and to establish the conditions of stability more appropriate to begin the preparation of pilot reagents. (Author)

  11. Low-cost production of proinsulin in tobacco and lettuce chloroplasts for injectable or oral delivery of functional insulin and C-peptide.

    Science.gov (United States)

    Boyhan, Diane; Daniell, Henry

    2011-06-01

    Current treatment for type I diabetes includes delivery of insulin via injection or pump, which is highly invasive and expensive. The production of chloroplast-derived proinsulin should reduce cost and facilitate oral delivery. Therefore, tobacco and lettuce chloroplasts were transformed with the cholera toxin B subunit fused with human proinsulin (A, B, C peptides) containing three furin cleavage sites (CTB-PFx3). Transplastomic lines were confirmed for site-specific integration of transgene and homoplasmy. Old tobacco leaves accumulated proinsulin up to 47% of total leaf protein (TLP). Old lettuce leaves accumulated proinsulin up to 53% TLP. Accumulation was so stable that up to ~40% proinsulin in TLP was observed even in senescent and dried lettuce leaves, facilitating their processing and storage in the field. Based on the yield of only monomers and dimers of proinsulin (3 mg/g leaf, a significant underestimation), with a 50% loss of protein during the purification process, one acre of tobacco could yield up to 20 million daily doses of insulin per year. Proinsulin from tobacco leaves was purified up to 98% using metal affinity chromatography without any His-tag. Furin protease cleaved insulin peptides in vitro. Oral delivery of unprocessed proinsulin bioencapsulated in plant cells or injectable delivery into mice showed reduction in blood glucose levels similar to processed commercial insulin. C-peptide should aid in long-term treatment of diabetic complications including stimulation of nerve and renal functions. Hyper-expression of functional proinsulin and exceptional stability in dehydrated leaves offer a low-cost platform for oral and injectable delivery of cleavable proinsulin. © 2010 The Authors. Plant Biotechnology Journal © 2010 Society for Experimental Biology, Association of Applied Biologists and Blackwell Publishing Ltd.

  12. A method of quality control in continuous for the thyroid hormones radioimmunoassay

    International Nuclear Information System (INIS)

    Savoie, J.C.; Kawadry, G.; Leger, F.A.; Hantour, Z.; Baulieu, J.L.

    1980-01-01

    The exploration of the thyroid function requires nowadays the T4, T3 and TSH radioimmunoassays. These assays, performed several times each week, raise the problem as to how control the quality of every new series and of every result. The authors describe the principle features of a program devised to automatically control 'in continuous' the quality of the radioimmunoassays. This program was developed on a SIMIS 3-INFORMATEK system. It is derived from Rodbard's work, uses Logit-Log transformation and ensures the consistent interseries control of many characteristic parameters. No series nor individual results are exploited i.e. edited without prior control of quality a decision from which is made to validate or reject. This program is but one solution -among many others possible- corresponding to a necessity: the need presently felt and perhaps to-morrow requested for some permanent quality control of the results of radioimmunoassays [fr

  13. Process for preparation of a solid-phase radioimmunoassay support and use thereof

    International Nuclear Information System (INIS)

    Meriadec, B.; Roubertie, P.

    1979-01-01

    A process is described for the preparation of a support useful in radioimmunoassay chromatographic columns. The process involves the preparation of a chromatographic gel capable of selectively retaining one or more components contained in an antigen-antibody-containing solution. The gel is bound to the appropriate antiserum, then freeze-dried, pulverized and compressed into a tablet. The tablet support swells upon contact with an antigen-antibody-containing solution to conform to the shape of the columns. An example of the application of this support in the radioimmunoassay of thyroid-stimulating hormone is described. This type of support is also particularly useful in second antibody solid phase radioimmunoassays since there is no limit to the size of the antigen to which this technology may be applied. (U.K.)

  14. Detection and purification of rat and goat immunoglobulin G antibodies using protein G-based solid phase radioimmunoassays

    International Nuclear Information System (INIS)

    Nilson, B.; Aakerstroem, B.; Bjoerck, L.

    1986-01-01

    Using the newly described streptococcal surface protein, protein G, which has powerful immunoglobulin G binding properties, solid-phase radioimmunoassays were developed for the quantitation of goat and rat immunoglobulin G bound to the plastic surface of microtiter plates. The binding of goat immunoglobulin G to the surface via a specific antigen (guinea pig alpha 1 -microglobulin) permitted the determination of antigen-specific antibodies with a detection limit of 50-100 ng. Optimum assay conditions were established and the whole assay procedure could be brought to completion at room temperature in less than a working day. The value of the assays was illustrated by monitoring rat and goat immunoglobulin G antibodies during their purification from whole sera by classical chromatographic procedures. (Auth.)

  15. Radioimmunoassays for lg classes G, A, M, D, and E in spinal fluids: normal values of different age groups

    International Nuclear Information System (INIS)

    Nerenberg, S.T.; Prasad, R.

    1975-01-01

    Radioimmunoassay procedures of sufficient sensitivity (lgG, 0.5 μg per 100 μl; lgA, 25.0 ng. per 100 μl; lgM, 10.0 ng. per 100 μl; lgD, 0.5 U.* per 100 μl; and lgE, 1.0 U.* per 100 μl) were developed to detect and quantitate all 5 immunoglobulin classes in the cerebrospinal fluid on small aliquots (1 ml.) of unconcentrated cerebrospinal fluid. All 5 immunoglobulin classes were routinely detected in normal individuals for the first time, the levels varying with different age groups for lgG and A but not for the remaining immunoglobulin classes. Race and sex had no effect. Standardization of techniques and establishment of normal values for different age groups sets the stage for determination of immunoglobulin changes related to central nervous system disease

  16. Easy and reliable radioimmunoassay of serum androstenedione: age-related normal values in 252 females aged 2 to 70 years

    Energy Technology Data Exchange (ETDEWEB)

    Hummer, L.; Nielsen, M.D.; Christiansen, C. (Glostrup Hospital (Denmark))

    1983-06-01

    A simple, non-chromatographic radioimmunoassay for the measurement of androstenedione (A-dione) in serum and based on a commercially available antiserum is described. The antibody-bound fraction was separated from the free fraction by a gel-centrifugation procedure. The method was used to establish reference values for normal females, based on determination in 252 normal females from 2 to 70 years of age. The data support the statement that the decline with age after puberty in the overall production of A-dione is mainly caused by a reduction in the adreno-derived A-dione, since the mean concentration of A-dione in age-matched pre- and postmenopausal women was very similar.

  17. Assessment of plasminogen synthesis in vitro by mouse tumor cells using a competition radioimmunoassay for mouse plasminogen

    International Nuclear Information System (INIS)

    Roblin, R.O.; Bell, T.E.; Young, P.L.

    1978-01-01

    A sensitive, specific competition radioimmunoassay for mouse plasmin(ogen) has been developed in order to determine whether mouse tumor cells can synthesize plasminogen in vitro. The rabbit anti-BALB/c mouse plasminogen antibodies used in the assay react with the plasminogen present in serum from BALB/c, C3H, AKR and C57BL/6 mice, and also recognized mouse plasmin. The competition radiommunoassay can detect as little as 50 ng of mouse plasminogen. No competition was observed with preparations of fetal calf, human and rabbit plasminogens. A variety of virus-transformed and mouse tumor cell lines were all found to contain less than 100 ng mouse plasminogen/mg of cell extract protein. Thus, if the plasminogen activator/plasmin system is important in the growth or movement of this group of tumor cells, the cells will be dependent upon the circulatory system of the host for their plasminogen supply. (Auth.)

  18. Acute viral hepatitis in adults. Comparison of the radioimmunoassay and counterimmunoelectrophoresis methods of detecting HB/sub s/Ag

    International Nuclear Information System (INIS)

    Wenzel, R.P.; Teates, C.D.; Galapon, Q.; Barczak, R.; Ling, C.M.; Overby, L.R.

    1975-01-01

    The radioimmunoassay (RIA) and counterimmunoelectrophoretic (CIE) methods were compared in detecting hepatitis B antigen (HB/sub s/Ag) in 407 acute and 336 convalescent sera of adults with viral hepatitis. The CIE method demonstrated that 41 percent of acute and 28 percent of 14- to 17-day serum specimens were HB/sub s/Ag-positive. The RIA method demonstrated seropositivity in 60 percent of acute and 56 percent of convalescent specimens (P less than .001). Eighty-four percent of coded specimens initially positive for HB/sub s/Ag by RIA were found to have subtype antigenic determinants d or y; 92 percent of the HB/sub s/Ag-negative controls were negative for subtype antigens, confirming the specificity of the RIA test. RIA subtyping data corroborated earlier work with immunodiffusion techniques. (U.S.)

  19. Development of a heterologous radioimmunoassay for the measurement of human prolactin in serum

    International Nuclear Information System (INIS)

    Vieira, J.G.H.; Russo, E.M.K.; Lengyel, A.M.J.; Maciel, R.M.B.

    1981-01-01

    The development of a heterologous radioimmunoassay method is described for the measurement of human prolactin in serum. Antisera were produced in rabbits using ovine prolactin as the immunogen; the best antiserum produced enebled the development of a simple and rapid method, with sufficient sensitivity (2ng/ml). The cross reactivity with human growth hormone and with placental lactogen was inferior to 0.03%. The labelling of human prolactin was done using the Lactoperoxidase method, followed by a column chromatography purification in a Sephadex G-100. Using 153 sera, the described method was compared with a homologous radioimmunoassay for human prolactin, and no significant difference was shown. (Author) [pt

  20. Development and characterization of a homologous radioimmunoassay for deer mouse (Peromyscus maniculatus bairdii) prolactin

    International Nuclear Information System (INIS)

    Marr, G.A.; Colosi, P.; Desjardins, C.; Talamantes, F.

    1983-01-01

    A highly specific and sensitive homologous radioimmunoassay has been developed for the secreted form of prolactin from the deer mouse Peromyscus maniculatus bairdii. Peromyscus serum and pituitary homogenates displayed paralled dilution response curves, and no cross reaction was seen with either mouse prolactin, mouse growth hormone or rat prolactin. The assay was sensitive to 25 picograms per tube and the intra- and inter-assay coefficients of variation were 5 and 3.6%, respectively. In addition, the authors have demonstrated that Peromyscus prolactin does not show parallel displacement in a homologous radioimmunoassay utilized for measuring prolactin in the common laboratory mouse

  1. Heterophilic antibodies interfering with radioimmunoassay. A false-positive pregnancy test

    Energy Technology Data Exchange (ETDEWEB)

    Vladutiu, A.O.; Sulewski, J.M.; Pudlak, K.A.; Stull, C.G.

    1982-11-19

    A young woman with amenorrhea had a consistently positive pregnancy test result (serum radioimmunoassay measurement of ..beta..-human chorionic gonadotropin hormone). No fetal or placental tissue was found after uterine curettage and exploratory laparotomy. The false-positive pregnancy test result was due to heterophilic antibovine and antigoat antibodies in the patient's serum. These antibodies interfered with radioimmunoassays using goat antibodies. This case shows that serum heterophilic antibodies can interfere with immunoassays and result in unnecessary diagnostic procedures and/or unnecessary treatment.

  2. Heterophilic antibodies interfering with radioimmunoassay. A false-positive pregnancy test

    International Nuclear Information System (INIS)

    Vladutiu, A.O.; Sulewski, J.M.; Pudlak, K.A.; Stull, C.G.

    1982-01-01

    A young woman with amenorrhea had a consistently positive pregnancy test result (serum radioimmunoassay measurement of #betta#-human chorionic gonadotropin hormone). No fetal or placental tissue was found after uterine curettage and exploratory laparotomy. The false-positive pregnancy test result was due to heterophilic antibovine and antigoat antibodies in the patient's serum. These antibodies interfered with radioimmunoassays using goat antibodies. This case shows that serum heterophilic antibodies can interfere with immunoassays and result in unnecessary diagnostic procedures and/or unnecessary treatment

  3. What type of statistical model to choose for the analysis of radioimmunoassays

    International Nuclear Information System (INIS)

    Huet, S.

    1984-01-01

    The current techniques used for statistical analysis of radioimmunoassays are not very satisfactory for either the statistician or the biologist. They are based on an attempt to make the response curve linear to avoid complicated computations. The present article shows that this practice has considerable effects (often neglected) on the statistical assumptions which must be formulated. A more strict analysis is proposed by applying the four-parameter logistic model. The advantages of this method are: the statistical assumptions formulated are based on observed data, and the model can be applied to almost all radioimmunoassays [fr

  4. The use of the radioimmunoassay for detection of diethylstilbestrol in fecal samples of fattened calves

    International Nuclear Information System (INIS)

    Agthe, O.

    1980-01-01

    A radioimmunoassay for diethylstilbestrol (DES) in fecal samples of fattened calves is described. The antibody used in this test showed no cross reactions with natural estrogens or other steroids. Blank values (fecal samples without DES) varied between 0 an 4,9 ng DES-equivalent/g sample. The distribution of blank values shows the significant proof of existence of DES in concentrations above 10 ng/g sample. The method has been applied for the control of living calves at the producer. Examples of illegal DES applications are given. The described radioimmunoassay is suitable for routine analysis as a control for illegal estrogen treatment. (orig.) [de

  5. Labelling of human follicle stimulant hormone with 125I, for radioimmunoassay

    International Nuclear Information System (INIS)

    Pinto, H.; Werner, R.S.; Lerario, A.C.; Toledo e Souza, I.T. de; Wajchenberg, B.L.; Pieroni, R.R.

    1976-01-01

    An efficient labeling of human Follicle Stimulant Harmone is essential to development of sensitive radioimmunoassays. Iodination by Chloramine T method frequently is subject to severe iodination damage and some preparations are unaccetable for radioimmunoassays. Modifications to the Hunter method, changing incubation time, reaction temperature and reducing Chloramine T amount used in the reaction, were performed in obtaining a more effective labeling. FSH-125 I fraction obtained from Sephadex G-75 column purification presented excellent immunoreactivity and quality control of the steps of the reaction demonstrated a high percentage (90%) of intact Follicle Stimulant Hormone [pt

  6. CA 125 radioimmunoassay for the diagnosis and assessment of the effectiveness of therapy of ovarian cancer

    International Nuclear Information System (INIS)

    Sagan, D.L.; Chebotareva, Eh.D.; Evtushenko, G.V.

    1989-01-01

    The paper is concerned with the results of CA-125 radioimmunoassay in 163 patients (584 tests) with benign and malignant ovarian diseases and other small pelvic diseases which were diagnosed before operation as ovarian tumors. CA-125 radioimmunoassay can be used in combination with other methods for investigation of patients with suspected ovarian cancer and for differential diagnosis of malignant ovarian tumors to distinguish them from other malignant tumors of the small pelvis. The investigation of CA-125 indices in the course of disease was indicative of the effectiveness of antitumor therapy

  7. Measurement of plasma 11-deoxycorticosterone levels by radioimmunoassay in man

    International Nuclear Information System (INIS)

    Fukuchi, Soitsu; Nakajima, Katsuo; Takenouchi, Takahiko; Nishisato, Koji

    1974-01-01

    A radioimmunoassay procedure has been developed to measure 11-deoxycorticosterone (DOC) in human peripheral plasma. DOC-oxime was coupled with porcine gamma globulin and antibodies produced in rabbits. One to 3 ml of plasma, with 1, 2 3 H-DOC added for recovery, was extracted with dichloromethane and purification achieved by a silica gel column and by one paper chromatograph. After overnight incubation of the antibody-steroid mixture at 4 0 C, bound and free fractions were separated using ammonium sulfate. The mean recovery of 3 H-DOC, after extraction and chromatography, was 84.6 +- 7.4%. The method showed adequate specificity, precision and accuracy. Normal plasma DOC levels were found to be 4.4 +- 2.5 ng/100 ml (n=8). Plasma DOC levels were almost normal (0.3 - 26.8 ng/100 ml) in fifteen patients with benign essential hypertension. The mean level of 8.1 +- 8.2 ng/100 ml obtained in hypertensive patients with suppressed plasma renin activity, was not significantly different from normal. Plasma DOC showed a high level, 3.0 - 30.5 (11.4 +- 7.5) ng/100 ml, in 9 patients with primary aldosteronism. Four out of 8 patients with Cushing's syndrome were found to have elevated plasma DOC levels. Higher levels of 21.2 +- 15.8 ng/100 ml were found in 5 patients with adrenal hyperplasia than those of 12.3 +- 8.0 ng/100 ml in 3 with adrenal adenoma. Plasma DOC levels were high, 113 - 176 ng/100 ml, in 2 patients with 17α-hydroxylase deficiency. ACTH administered to 5 subjects produced a mean increase in plasma DOC from 4.8 to 25.8 ng/100 ml. Angiotensin II infused at a rate of 10 ng/kg/min for 30 min into 4 subjects did not increase mean plasma DOC. Similarly, dietary sodium restriction or postural change did not increase plasma DOC. (auth.)

  8. The radioimmunoassay of plasma oxytocin in pregnancy and at parturition

    International Nuclear Information System (INIS)

    Kogure, Satohisa

    1976-01-01

    The titer of the antiserum obtained by inoculating oxytocin-bovine serum albumin antigen into mature male rabbits was 1:64,000 in the final dilution, and the rate of conjugation with labeled-oxytocin was 34%. The cross reaction rate of the antiserum was 0.01% or below, both for lysine vasopressin and arginine vasopressin. The sensitivity of the radioimmunoassay using this antiserum was 5μIU. When a known quantity of oxytocin was added to plasma for measurement, the mean recovery rate was about 93%. The blood oxytocin concentration was 6.1+-2.5μIU/ml (ml omitted hereafter) in the early stage of pregnancy, 12.5+-6.0μIU in the middle stage, and 27.0+-7.5μIU in the terminal stage. The oxytocin concentration in the maternal blood was 34.1+-4.9μIU in the second stage, the concentration in the umbilical arterial blood immediately after delivery 3.5+-5.3μIU, and that in the umbilical venous blood 30.0+-4.2μIU. In cases of caesarean section not in labor, the oxytocin concentration in the maternal blood was 27.1+-6.6μIU, that in the umbilical arterial blood 25.1+-5.4μIU, and that in the umbilical venous blood 25.4+-5.4μIU. In cases of caesarean section in labor, the oxytocin concentration in the maternal blood was 37.1+-7.1μIU, that in the umbilical arterial blood 31.4+-6.7μIU, and that in the umbilical venous blood 27.0+-7.8μIU. The half-life of the oxytocin in the peripheral blood in cases injected with oxytocin was 5-10 minutes. When prostaglandin F2α was administered intravenously, the oxytocin concentration in the peripheral blood was increased in cases in labor. (Chiba, N.)

  9. Sensitive radioimmunoassay of total thyroxine (T4) in horses using a simple extraction method.

    Science.gov (United States)

    Tangyuenyong, Siriwan; Nambo, Yasuo; Nagaoka, Kentaro; Tanaka, Tomomi; Watanabe, Gen

    2017-07-28

    Most thyroid hormone determinations in animals are based on immunoassays adapted from those used to test human samples, which may not reflect the actual values of thyroid hormone in horses because of the presence of binding proteins. The aims of the present study were i) to establish a novel radioimmunoassay (RIA) using a more simple and convenient method to separate binding proteins for the measurement of total thyroxine (T4) in horses and ii) to validate the assay by comparing total T4 concentrations in yearling horses raised in different climates. Blood samples were collected from trained yearlings in Hokkaido (temperate climate) and Miyazaki (subtropical climate) in Japan and from adult horses in estrus and diestrus. T4 was extracted from both serum and plasma using modified acid ethanol cryo-precipitation and sodium acetate ethanol methods. Circulating total T4 concentrations were determined by RIA. T4 concentration by sodium acetate ethanol was appropriately detectable rather than sodium salicylate method and was the same as for acid ethanol method. Furthermore, this sodium acetate ethanol method required fewer extraction steps than the other methods. Circulating T4 concentrations in yearlings were 225.98 ± 20.89 ng/ml, which was higher than the previous reference values. With respect to climate, T4 levels in Hokkaido yearlings tended to be higher than those in Miyazaki yearlings throughout the study period. These results indicated that this RIA protocol using a modified sodium acetate ethanol separation technique might be an appropriate tool for specific measurement of total T4 in horses.

  10. Isolation characterization and radioimmunoassay of rat alpha-macrofetoprotein (acute phase A2 macroglobulin)

    International Nuclear Information System (INIS)

    Hudig, D.; Sell, S.

    1979-01-01

    Rat alpha-macrofetoprotein (AMF) has been isolated and purified by antibody affinity chromatography and quantitated using a double antibody radioimmunoassay (RIA) with a sensitivity of 20 ng. Two forms of AMF, differing in reference mobilities (R) in 5% polyacrylamide gels and in isoelectric focusing points (pI), are present in serum. The Rsub(f0.10)AMF has a pI of 4.35 and Rsub(f0.25) AMF a pI of 4.65. Rsub(f0.25) AMF competes 2.2 times better than Rsub(f0.10) AMF in an RIA with 125 I Rsub(f0.25) AMF as the predominant antigen. The two forms do not differ substantially in mol. wt. AMF has a mol. wt of 700.000 +- 70.000 determined by SDS polyacrylamide gel electrophoresis. Dithiothreitol reduction of AMF resulted in six different chains, the largest mol. wt 175.000. It is suggested that the five smaller chains are the result of interaction of AMF with endoproteases. The E 280 sup(1%) of AMF is 9.6 +- 0.3 by the biuret method using bovine serum albumin as a standard and 10.6 +- 0.3 by microKjeldahl N analysis. Amino-acid analysis of AMF is compared with the analyses recently reported by others. Normal adult rat serum AMF concentrations determined for two groups of rats are 17 +- 2 and 32 +- 6 μg/ml. (author)

  11. Incidence and specificity of antibodies to types I, II, III, IV, and V collagen in rheumatoid arthritis and other rheumatic diseases as measured by 125I-radioimmunoassay

    International Nuclear Information System (INIS)

    Stuart, J.M.; Huffstutter, E.H.; Townes, A.S.; Kang, A.H.

    1983-01-01

    Antibodies to human native and denatured types I, II, III, IV, and V collagens were measured using 125I-radioimmunoassay. Mean levels of binding by sera from 30 rheumatoid arthritis patients were significantly higher than those from 20 normal subjects against all of the collagens tested. The relative antibody concentration was higher in synovial fluid than in simultaneously obtained serum. Many patients with gout or various other rheumatic diseases also had detectable anticollagen antibodies. With a few notable exceptions, the majority of the reactivity detected in all patient groups was directed against covalent structural determinants present on all of the denatured collagens, suggesting a secondary reaction to tissue injury

  12. Development and clinical application of radioimmunoassay techniques for the measurement of thyroid and parathyroid hormones. Part of a coordinated programme on in vitro assay techniques

    International Nuclear Information System (INIS)

    Carlos Stevenson, R.

    1976-08-01

    Radioimmunoassay procedures were utilized to investigate the aetiology and pathology of endemic goitre in Pirque and Petregosa, Chile. The studies were carried out on adult woman and on children. The basal levels of TSH, T3 and T4 were determined. Significant differences were observed between the results in both localities. No children under the age of 5 were observed with goitre in Pedregosa, but goitre incidence increased with age up to 74% at age 18, the percentage being higher for femals. Conclusion: Aetiology and pathology of goitre may vary considerably even within a given country and both dietary and ethnic factors may play a part in this variation

  13. A novel radioimmunoassay of 7-oxo-DHEA and its physiological levels

    Czech Academy of Sciences Publication Activity Database

    Kazihnitová, H.; Zamrazilová, L.; Hill, M.; Lapčík, O.; Pouzar, Vladimír; Hampl, R.

    2007-01-01

    Roč. 72, č. 4 (2007), s. 342-350 ISSN 0039-128X Grant - others:GA MZd(CZ) NR7815 Institutional research plan: CEZ:AV0Z40550506 Keywords : 7-oxo-dehydroepiandrosterone * radioimmunoassay * GC-MS * serum levels Subject RIV: CC - Organic Chemistry Impact factor: 2.143, year: 2007

  14. Preparation, purification and characterization of 125I-glucagon used for radioimmunoassay

    International Nuclear Information System (INIS)

    Ruehlmann, C.; Poege, A.; Stollmaier, P.; Akademie der Wissenschaften der DDR, Leipzig. Zentralinstitut fuer Isotopen- und Strahlenforschung)

    1988-01-01

    A method for the radioactive labelling of glucagon with Na 125 I with the help of chloramine T for the use in radioimmunoassay is described. The purification of 125 I-glucagon with polyacrylamide gel electrophoresis, the characterization of the tracer, its stability and the immunological properties are described. (author)

  15. Simultaneous detection of Hepatitis B surface antigen and its antibody by radioimmunoassay

    International Nuclear Information System (INIS)

    Crouzat-Reynes, Gerard; Perigois, Francois; Lecureuil, Michel; Lejeune, Bernard

    1981-01-01

    The authors describe an original radioimmunoassay which allows the simultaneous detection of hepatitis B surface antigen and its antibody in a biological sample. Antigen and antibody are indiscriminately detected in a first step and then distinguished in a second step using the same reagents [fr

  16. Filter radioimmunoassay, a method for large-scale serotyping of Neisseria meningitidis.

    NARCIS (Netherlands)

    S. de Marie (Siem); J.H.J. Hoeijmakers (Jan); J.T. Poolman; H.C. Zanen

    1984-01-01

    textabstractA simple and rapid filter radioimmunoassay method can be used to serotype meningococcal strains on a large scale. The technique consists of simultaneous inoculation of 96 strains on nitrocellulose filters. The resulting colonies can be processed in situ, by extraction and fixation,

  17. Elevated serum free thyroxine by thyroxine analog radioimmunoassays in euthyroid patients with familial dysalbuminemic hyperthyroxinemia

    International Nuclear Information System (INIS)

    Rajatanavin, R.; Fournier, L.; DeCosimo, D.; Abreau, C.; Braverman, L.E.

    1982-01-01

    A study was done to ascertain whether the serum free T4 measured by free T4 radioimmunoassay kits would, like equilibrium dialysis, be normal in patients with familial dysalbuminemic hyperthyroxinemia. Five free T4 radioimmunoassay kits were used to measure free T4 in serum samples from 19 patients with familial dysalbuminemic hyperthyroxinemia and 20 healthy volunteers. Values (mean +/- SE) for T4, free T4 index, and free T4 (equilibrium dialysis) in these normal subjects and patients with familial dysalbuminemic hyperthyroxinemia, respectively, were as follows: T4, 8.1 +/- 0.2 and 18.3 +/- 0.7 μg/dL; free T4 index, 3.1 +/- 0.1 and 7.3 +/- 0.3 μg/dL; free T4, 1.4 +/- 0.1 and 1.2 +/- 0.1 ng/dL. The following free T4 radioimmunoassay methods were used: antibody coated microfine silica, microencapsulated antibody, two-step antibody-coated tube, and one-step 125 I-T4 analog (2 kits). The present findings in patients with familial dysalbuminemic hyperthyroxinemia and previous observations in ill euthyroid patients suggest that serum free T4 measured by some radioimmunoassay methods must be interpreted with caution in these two clinical situations

  18. Radio-immunoassays for glucagon-like peptides 1 and 2 (GLP-1 and GLP-2)

    DEFF Research Database (Denmark)

    Orskov, C; Holst, J J

    1987-01-01

    Gene-sequencing studies have shown that the glucagon precursor contains two additional glucagon-like sequences, the so-called glucagon-like peptides 1 and 2 (GLP-1 and GLP-2). We developed radio-immunoassays against synthetic peptides corresponding to these sequences. Antisera were raised in rabb...

  19. Conditions and limits of serum LH radioimmunoassay in normal, hypophysectomised or castred rats

    International Nuclear Information System (INIS)

    Andre, M.; Boucher, D.; Thieblot, L.

    1976-01-01

    Serum LH was measured by radioimmunoassay (NIAMD Kits) free and linked hormones were separated by double antibodies method. Influence of concentration on antibody-hormone complex is studied. Hypophysectomised rats serum does not modify results. The standard (rat LH-RPl) has the same action as serum LH. Rat serum LH contents are measured in normal or castred rats [fr

  20. Single vagus nerve stimulation reduces early postprandial C-peptide levels but not other hormones or postprandial metabolism.

    Science.gov (United States)

    Tang, M W; van Nierop, F S; Koopman, F A; Eggink, H M; Gerlag, D M; Chan, M W; Zitnik, R; Vaz, F M; Romijn, J A; Tak, P P; Soeters, M R

    2018-02-01

    A recent study in rheumatoid arthritis (RA) patients using electrical vagus nerve stimulation (VNS) to activate the inflammatory reflex has shown promising effects on disease activity. Innervation by the autonomic nerve system might be involved in the regulation of many endocrine and metabolic processes and could therefore theoretically lead to unwanted side effects. Possible effects of VNS on secretion of hormones are currently unknown. Therefore, we evaluated the effects of a single VNS on plasma levels of pituitary hormones and parameters of postprandial metabolism. Six female patients with RA were studied twice in balanced assignment (crossover design) to either VNS or no stimulation. The patients selected for this substudy had been on VNS therapy daily for at least 3 months and at maximum of 24 months. We compared 10-, 20-, and 30-min poststimulus levels to baseline levels, and a 4-h mixed meal test was performed 30 min after VNS. We also determined energy expenditure (EE) by indirect calorimetry before and after VNS. VNS did not affect pituitary hormones (growth hormone, thyroid stimulating hormone, adrenocorticotropic hormone, prolactin, follicle-stimulating hormone, and luteinizing hormone), postprandial metabolism, or EE. Of note, VNS reduced early postprandial insulin secretion, but not AUC of postprandial plasma insulin levels. Cortisol and catecholamine levels in serum did not change significantly. Short stimulation of vagal activity by VNS reduces early postprandial insulin secretion, but not other hormone levels and postprandial response. This suggests VNS as a safe treatment for RA patients.

  1. Radioimmunoassay of serum concentrations of melatonin in sheep exposed to different lighting regimens

    International Nuclear Information System (INIS)

    Rollag, M.D.; Niswender, G.D.

    1976-01-01

    A specific and sensitive double-antibody radioimmunoassay for melatonin (N-acetyl-5-methoxytryptamine) was developed. The least detectable concentration of melatonin standard was 10 pmolar (2.3 pg/tube) with 50 percent inhibition resulting when the concentration was 100 pmolar (23 pg/tube). Inhibition curves obtained with increasing quantities of melatonin or increasing quantities of chloroform extracts of ovine sera were parallel. Concentrations of melatonin could be accurately determined when 31 to 1000 pg were added to 1 ml ovine serum. Serum samples with melatonin concentrations of 1000 pg/ml, 500 pg/ml and 75 pg/ml had intra-assay coefficients of variation of 9.1 percent, 8.6 percent, and 17.4 percent, respectively. The respective inter-assay coefficients of variation were 22.7 percent, 18.1 percent, and 37.1 percent. Ewes exposed to a 12 h light:12 h dark lighting regimen demonstrated a circadian rhythm in serum concentrations of melatonin. Concentrations ranged from 10 to 30 pg/ml during periods of light to 100 to 300 pg/ml during periods of dark. During exposure to continuous light, the circadian rhythm was abolished and concentrations of melatonin were maintained at 10 to 50 pg/ml. When exposed to conditions of continuous dark the circadian rhythm persisted. A precipitous drop in serum concentrations of melatonin resulted when ewes experiencing peak melatonin concentrations were exposed to light. Concentrations returned to peak levels when the lights were turned off 3.5 h later

  2. The Analysis of the Value of the Thyroid Autoantibody Measured by Radioimmunoassay

    International Nuclear Information System (INIS)

    Chung, Jae Hoon; Lee, Myung Shik; Cho, Bo Youn; Lee, Hong Kyu; Koh, Chang Soon; Min, Hun Ki; Lee, Mun Ho

    1987-01-01

    To evaluate the values of the thyroid autoantibody measured by radioimmunoassay (RIA) and compare it with hemagglutination method (HA) in the normal and the thyroid disease, data were obtained from total 618 persons; 236 healthy persons, 217 patients with Graves disease (including 113 patients with undertreated Graves' disease), 100 Hashimoto's disease, 31 thyroid nodule, and 34 simple goiter. RSR kit made in England was used and could be detected at least 3 U/ml. The positive rates of normal group were antirnicrosomal antibody (AMA) 31.8%, antithyroglobulin antibody (ATA) 44.5% by RIA and there was no considerable change in sex and age distribution. In Graves disease, the positive rates of AMA and ATA were 90.4, 76.9% by RIA, 85, 39% by HA. In Hashimoto's disease, 94,91% by RIA, and 87,48% by HA, respectively. The autoantibody titer by RIA in thyroid autoimmune disease as welt as in normal group was more sensitive than that by HA, especially in ATA. There were linear relationships between the titer of RIA and that of HA in AMA of Graves disease and AMA and ATA of Hashimotos disease. There was no relationship among thyroid autoantibody, free T, index, TBII, and TSH. The titers of AMA and ATA were found to decrease in patients with Graves disease during the course of antithyroid drug therapy. Of the 236 normal subjects, thirty-seven (15.7%) had concentrations of above 7.5 U/ml in AMA, forty-four (18. 6%) above 9 U/ml in ATA. These values were considered as the upper limit for the normal range. In Graves disease, 82,7, 53.8% were above 7.5, 9 U/ml, respectively; In Hashimoto's disease, HZ, 79% were positive. We conclude that RIA was more sensitive than HA in measuring the thyroid autoantibody, but we will study further more for determining the normal range and its interpretation.

  3. Exposure to environmental tobacco smoke measured by cotinine 125I-radioimmunoassay

    International Nuclear Information System (INIS)

    Knight, G.J.; Palomaki, G.E.; Lea, D.H.; Haddow, J.E.

    1989-01-01

    We describe a polyclonal-antiserum-based 125 I-radioimmunoassay for cotinine that is suitable for measuring nonsmokers' passive exposure to tobacco smoke in the environment. The standard curve ranged from 0.25 to 12.0 micrograms/L, with an estimated lower limit of sensitivity of 0.2 microgram/L (95% B/Bo = 0.2 microgram/L; 50% B/Bo = 4.0 micrograms/L). The median within-assay CVs for patients' samples with cotinine values from 0.4 to 1.3, 1.4 to 2.4, 2.5 to 4.6, and 4.7 to 15.6 micrograms/L were 13.9%, 7.2%, 5.1%, and 5.7%, respectively. Between-assay CVs for two quality-control sera with average values of 1.53 and 3.68 micrograms/L were 14.3% and 7.8%, respectively. Analytical recoveries of cotinine from smokers' sera diluted in zero calibrant ranged from 91% to 116%. Cotinine values determined on 79 paired sera and urines from nonsmokers showed significant correlation with self-reported exposure to environmental tobacco smoke (r = 0.49, P less than 0.001 for sera; r = 0.57, P less than 0.001 for urine). The log of the values for serum and urine cotinine were also significantly correlated (r = 0.85, P less than 0.001). Evidently, polyclonal antiserum can be used to develop a cotinine assay for measuring exposure to environmental tobacco smoke that compares well with that described for monoclonal-based assays

  4. Synthetic lung surfactants containing SP-B and SP-C peptides plus novel phospholipase-resistant lipids or glycerophospholipids

    Directory of Open Access Journals (Sweden)

    Robert H. Notter

    2016-10-01

    Full Text Available Background This study examines the biophysical and preclinical pulmonary activity of synthetic lung surfactants containing novel phospholipase-resistant phosphonolipids or synthetic glycerophospholipids combined with Super Mini-B (S-MB DATK and/or SP-Css ion-lock 1 peptides that replicate the functional biophysics of surfactant proteins (SP-B and SP-C. Phospholipase-resistant phosphonolipids used in synthetic surfactants are DEPN-8 and PG-1, molecular analogs of dipalmitoyl phosphatidylcholine (DPPC and palmitoyl-oleoyl phosphatidylglycerol (POPG, while glycerophospholipids used are active lipid components of native surfactant (DPPC:POPC:POPG 5:3:2 by weight. The objective of the work is to test whether these novel lipid/peptide synthetic surfactants have favorable preclinical activity (biophysical, pulmonary for therapeutic use in reversing surfactant deficiency or dysfunction in lung disease or injury. Methods Surface activity of synthetic lipid/peptide surfactants was assessed in vitro at 37 °C by measuring adsorption in a stirred subphase apparatus and dynamic surface tension lowering in pulsating and captive bubble surfactometers. Shear viscosity was measured as a function of shear rate on a Wells-Brookfield micro-viscometer. In vivo pulmonary activity was determined by measuring lung function (arterial oxygenation, dynamic lung compliance in ventilated rats and rabbits with surfactant deficiency/dysfunction induced by saline lavage to lower arterial PO2 to <100 mmHg, consistent with clinical acute respiratory distress syndrome (ARDS. Results Synthetic surfactants containing 5:3:2 DPPC:POPC:POPG or 9:1 DEPN-8:PG-1 combined with 3% (by wt of S-MB DATK, 3% SP-Css ion-lock 1, or 1.5% each of both peptides all adsorbed rapidly to low equilibrium surface tensions and also reduced surface tension to ≤1 mN/m under dynamic compression at 37 °C. However, dual-peptide surfactants containing 1.5% S-MB DATK + 1.5% SP-Css ion-lock 1 combined with

  5. Synthetic lung surfactants containing SP-B and SP-C peptides plus novel phospholipase-resistant lipids or glycerophospholipids.

    Science.gov (United States)

    Notter, Robert H; Gupta, Rohun; Schwan, Adrian L; Wang, Zhengdong; Shkoor, Mohanad Gh; Walther, Frans J

    2016-01-01

    This study examines the biophysical and preclinical pulmonary activity of synthetic lung surfactants containing novel phospholipase-resistant phosphonolipids or synthetic glycerophospholipids combined with Super Mini-B (S-MB) DATK and/or SP-Css ion-lock 1 peptides that replicate the functional biophysics of surfactant proteins (SP)-B and SP-C. Phospholipase-resistant phosphonolipids used in synthetic surfactants are DEPN-8 and PG-1, molecular analogs of dipalmitoyl phosphatidylcholine (DPPC) and palmitoyl-oleoyl phosphatidylglycerol (POPG), while glycerophospholipids used are active lipid components of native surfactant (DPPC:POPC:POPG 5:3:2 by weight). The objective of the work is to test whether these novel lipid/peptide synthetic surfactants have favorable preclinical activity (biophysical, pulmonary) for therapeutic use in reversing surfactant deficiency or dysfunction in lung disease or injury. Surface activity of synthetic lipid/peptide surfactants was assessed in vitro at 37 °C by measuring adsorption in a stirred subphase apparatus and dynamic surface tension lowering in pulsating and captive bubble surfactometers. Shear viscosity was measured as a function of shear rate on a Wells-Brookfield micro-viscometer. In vivo pulmonary activity was determined by measuring lung function (arterial oxygenation, dynamic lung compliance) in ventilated rats and rabbits with surfactant deficiency/dysfunction induced by saline lavage to lower arterial PO 2 to surfactants containing 5:3:2 DPPC:POPC:POPG or 9:1 DEPN-8:PG-1 combined with 3% (by wt) of S-MB DATK, 3% SP-Css ion-lock 1, or 1.5% each of both peptides all adsorbed rapidly to low equilibrium surface tensions and also reduced surface tension to ≤1 mN/m under dynamic compression at 37 °C. However, dual-peptide surfactants containing 1.5% S-MB DATK + 1.5% SP-Css ion-lock 1 combined with 9:1 DEPN-8:PG-1 or 5:3:2 DPPC:POPC:POPG had the greatest in vivo activity in improving arterial oxygenation and dynamic lung

  6. Surfactant protein C peptides with salt-bridges (“ion-locks” promote high surfactant activities by mimicking the α-helix and membrane topography of the native protein

    Directory of Open Access Journals (Sweden)

    Frans J. Walther

    2014-07-01

    Full Text Available Background. Surfactant protein C (SP-C; 35 residues in lungs has a cationic N-terminal domain with two cysteines covalently linked to palmitoyls and a C-terminal region enriched in Val, Leu and Ile. Native SP-C shows high surface activity, due to SP-C inserting in the bilayer with its cationic N-terminus binding to the polar headgroup and its hydrophobic C-terminus embedded as a tilted, transmembrane α-helix. The palmitoylcysteines in SP-C act as ‘helical adjuvants’ to maintain activity by overriding the β-sheet propensities of the native sequences.Objective. We studied SP-C peptides lacking palmitoyls, but containing glutamate and lysine at 4-residue intervals, to assess whether SP-C peptides with salt-bridges (“ion-locks” promote surface activity by mimicking the α-helix and membrane topography of native SP-C.Methods. SP-C mimics were synthesized that reproduce native sequences, but without palmitoyls (i.e., SP-Css or SP-Cff, with serines or phenylalanines replacing the two cysteines. Ion-lock SP-C molecules were prepared by incorporating single or double Glu−–Lys+ into the parent SP-C’s. The secondary structures of SP-C mimics were studied with Fourier transform infrared (FTIR spectroscopy and PASTA, an algorithm that predicts β-sheet propensities based on the energies of the various β-sheet pairings. The membrane topography of SP-C mimics was investigated with orientated and hydrogen/deuterium (H/D exchange FTIR, and also Membrane Protein Explorer (MPEx hydropathy analysis. In vitro surface activity was determined using adsorption surface pressure isotherms and captive bubble surfactometry, and in vivo surface activity from lung function measures in a rabbit model of surfactant deficiency.Results. PASTA calculations predicted that the SP-Css and SP-Cff peptides should each form parallel β-sheet aggregates, with FTIR spectroscopy confirming high parallel β-sheet with ‘amyloid-like’ properties. The enhanced

  7. Radioimmunoassay measurement of urinary ligandin excretion in nephrotoxin-treated rats

    International Nuclear Information System (INIS)

    Bass, N.M.; Kirsch, R.E.; Tuff, S.A.; Campbell, J.A.; Saunders, J.S.

    1979-01-01

    A radioimmunoassay (RIA) was used to establish normal urine excretion of ligandin, a renal tubular protein, in rats, and to study the pattern of ligandin excretion after nephrotoxin administration. Validation of RIA measurement of ligandin in urine is described. A normal range of 2-46 ng/h was obtained for ligandin excretion in rats (n = 24). The time course of ligandin excretion in HgCl 2 and K 2 Cr 2 0 7 treated rats correlated with the histological sequence of damage to the pars recta and pars convoluta of the proximal tubule respectively. Results confirm that renal ligandin is confined mainly to the pars recta of the proximal tubule and small quantities of the protein are present in the pars convoluta. Radioimmunoassay provides a sensitive and specific means for measuring ligandin in urine and is a valuable tool for the detection and study of renal tubular damage. (author)

  8. Quality characteristics of chemicals for the radioimmunoassay of thyroxine and thyrotropin

    International Nuclear Information System (INIS)

    Verdeja I, C.E.

    1994-01-01

    Radioimmunoassay is a form of saturation analysis in which the test material competes with labelled antigen for a limited amount of antibody, the amount of label displaced being a measure of the antigen in the test sample. In this country, the kits for Radioimmunoassay (RIA) are imported, and this increase the cost of it. Because this lack of production, the National Institute of Nuclear Research (ININ) has developed RIA's kits for the thyroxine (T 4 ), Thyrotropin (TSH) and Triyodotironine (T 3 ) hormones. This work presents the conclusions of the test recommended by the WHO. The quality test were: recuperation, cross reactions, basic parameters, intra and inter assay variations, sensibility and others. The results show that the RIA's kits of the ININ have a good behavior and can be use in the clinical laboratory. (Author)

  9. Radioimmunoassay screening and GC/MS confirmation of whole blood samples for drugs of abuse

    Energy Technology Data Exchange (ETDEWEB)

    Spiehler, V.R.; Sedgwick, P.

    From 1981 to 1984, an average of 300 radioimmunoassay screens on whole blood were performed each week in the authors laboratory. Most samples were screened for opiates phencyclidine and its analogs, barbiturates, and cocaine or its metabolite benzoylecgonine. A commercially available radioimmunoassay was used with modifications to facilitate screening of whole blood. Increasing sample size increased the sensitivity of the assay. Changing reagent concentration (1:1 dilution), incubation time, sample matrix (water, urine, or blood), or fraction counted (precipitate or supernatant) did not affect the utility of the standard curve or the sensitivity of the assay. All positive results for phencyclidine, opiates, cocaine, and related compounds were confirmed by GC/MA. Barbiturate positives were confirmed by UV spectrophotometry.

  10. The role of carbohydrates in the radioimmunoassay of human low-molecular-mass kininogen

    International Nuclear Information System (INIS)

    Turpeinen, U.; Kaerkkaeinen, T.

    1985-01-01

    The immunoreactivity of human low-molecular-mass kininogen from Cohn plasma fraction IV was investigated after deglycosylations and carbohydrate modifications by radioimmunoassay using the conformation-specific antiserum. Removal of all sialic acids, 44% of amino sugars and 63% of neutral sugars did not alter the immunoreactivity of the protein but the periodate-treated concanavalin A fractions showed strikingly diminished immunoreactivity. A conformational change could account for the observed effect of periodate on the decreased reactivity of the protein in radioimmunoassay. Externally added carbohydrates had no effect on immunoreactivity. The results suggest that the carbohydrate part of kininogen is not involved in the immunoreactivity although it accounts for the observed lectin-binding heterogeneity. (Auth.)

  11. Radioimmunoassay of renin-angiotensin-aldosterone in patients with adrenal tumors

    International Nuclear Information System (INIS)

    Slavnov, V.N.; Yakovlev, A.A.; Yugrinov, O.G.; Gandzha, T.I.

    1983-01-01

    The results are presented of a study of the renin-angiotensin-aldosterone system in 89 patients with aldosteronoma, corticosteroma, pheochromocytoma and hypertension. Radioimmunoassay was used to measure aldosterone concentration and renin activity in the peripheral blood and blood from vena cava inferior, the renal and adrenal veins, the circadian cycle of their content and the responsiveness of the glomerular zone of the adrenal cortex and the juxtaglomerular renal system under the influence of lasix intake and the change over from a horizontal into vertical position. Patients with adrenal tumors have shown disorders of renin-angiotensin-aldosterone function. Radioimmunoassay of the renin-angiotensin-aldosterone system promotes early detection of adrenal tumors in the general population of patients with hypertension and can be used for control over therapeutic efficacy

  12. Serum progesterone levels using radioimmunoassay during the oestrous cycle of indigenous Damascus does

    International Nuclear Information System (INIS)

    Zarkawi, M.

    2000-11-01

    An experiment was conducted on Damascus does to characterize the oestrous cycle, the activity of the corpus luteum and to determine normal progesterone profiles during different phases of the oestrous cycle using radioimmunoassay. Fifteen indigenous cycling Damascus does were used during the normal breeding season for two consecutive oestrous cycles. Average length of the oestrous cycles was 21.2 ± 1.5 days (range: 19 - 26 days), divided into: 2.9 ± 0.8 days (2 - 5 days), where progesterone level was low averaging 0.69 ± 0.85 nmol l -1 (range: 0.00 - 3.08 nmol l -1 , followed by a sharp increase in progesterone secretion, i.e. presence of active corpora lutea, lasted on average for 15.3 ± 1.4 days (range: 13 - 20 days), with an average progesterone level of 13.4 nmol l -1 (range: 3.26 - 27.98 nmol l -1 ), followed by a sharp decline in progesterone level, i.e. inactive corpora lutea, lasted on average for 3.1 ± 0.6 days (range: 2 - 5 days), with an average progesterone level of 0.68 nmol l -1 (range: 0.00 - 2.81 nmol l -1 ). Maximum progesterone level during the luteal phase averaged 18.67 ± 3.15 nmol l -1 (range: 14.00 - 27.98 nmol l -1 ), occurred on average on 12.2 ± 3.2 days of the oestrous cycle. It was possible, for the first time, to characterize the oestrous cycle of the Damascus doe, and to determine normal progesterone profiles during different phases of oestrous cycle. Based on the results reported above, it is also concluded that progesterone levels under 3.18 nmol l -1 were found on average during 2.9 days at the start of the oestrous cycle and during 3.1 days at the end of the oestrous cycle (follicular phase), and that progesterone levels above 3.18 nmol l -1 were found during the luteal phase lasting on average 15.3 days. (Author)

  13. Radioimmunoassay for Zearalenone and Zearalanol in Human Serum: Production, Properties, and Use of Porcine Antibodies

    OpenAIRE

    Thouvenot, Daniel; Morfin, Robert F.

    1983-01-01

    To produce antigens susceptible to raise antibodies for resorcylic acid lactones, the 6′-carboxymethyloxime derivatives of zearalenone and zearalanone were bound to bovine serum albumin. Pigs could be immunized by using these antigens, the best titer in antibodies being obtained with the zearalenone antigen. The porcine antibodies were specific for the resorcylic acid lactones of structural resemblance with zearalenone. This specificity made the antibodies usable for a radioimmunoassay of zea...

  14. Radioimmunoassay of ferritin, CEA and prolactin for assessment of prognosis and efficacy of breast cancer therapy

    International Nuclear Information System (INIS)

    Sklyar, S.Yu.; Chebotareva, Eh.D.; Ganul, V.L.; Korolev, V.I.

    1987-01-01

    The levels of tumor markers - CEA, deritin and prolactin (the hormone of the anterior pituitary gland) were studied in the blood serum of 178 breast cancer patients in the menopause during combined therapy using a radioimmunoassay. This combination was shown to be informative for assessment of prognosis of disease and efficacy of antitumor therapy which was confirmed by clinical and x-ray findings and observation of a tumor process in breast cancer patients over a 5-year period

  15. The insulin radioimmunoassay kit prepared by IPEN-CNEN/SP - Brazil

    International Nuclear Information System (INIS)

    Mesquita, C.H. de; Silva, C.P.G. da; Hamada, M.M.

    1985-11-01

    The specification and methodological aspects of the insulin radioimmunoassay kit produced by IPEN-CNEN/SP - Brazil are described. The limitations taking care and the following quality control parameters or procedures are discussed: specific radioactivity, comparison between two insulin - 125 I purification procedures, affinity constant 'K' of the antigen - antibody reaction, minimal detectable dose (MDD), kinetics degradation of the radioinsulin, radioassay imprecision profile, radioassay performance temperature dependence and normal values histogram. (Author) [pt

  16. Preparation of iodine - 125 - labeled insulin for radioimmunoassay: comparison of chloramine T and iodogen iodination

    International Nuclear Information System (INIS)

    Toledo e Souza, I.T. de; Giannella Neto, D.; Wajchenberg, B.L.

    1988-05-01

    Stoichiometric iodination of porcine insulin was performed to the general method of Hunter and Greenwood with modifications recommended by Roth. These method was compared with radioidination using Iodogen. Films of Iodogen react rapidly in the solid phase with aqueous mixtures of I - and proteins. For two methods satisfactory activity of the labeled porcine insulin was obtained and characteristics of the radioimmunoassay were studied. (author) [pt

  17. Use of a rapid hCG-beta-subunit radioimmunoassay in acute gynaecological emergencies

    International Nuclear Information System (INIS)

    Seppala, M.; Tontti, K.; Ranta, T.; Stenman, U.-H.; Chard, T.

    1980-01-01

    Chorionic gonadotrophin (hCG) was measured by a rapid and sensitive radioimmunoassay in 100 female patients with lower abdominal pain attending an emergency department. Of the 24 subjects with a positive result, 22 had evidence of pregnancy (ectopic or uterine). Of the 76 patients with negative results, 3 had some evidence of pregnancy. This test may be of considerable practical value in the differential diagnosis of acute abdominal emergencies in women of reproductive age. (author)

  18. Three magnetic particles solid phase radioimmunoassay for T4: Comparison of their results with established methods

    International Nuclear Information System (INIS)

    Bashir, T.

    1996-01-01

    The introduction of solid phase separation techniques is an important improvement in radioimmunoassays and immunoradiometric assays. Magnetic particle solid phase method has additional advantages over others, as the separation is rapid and centrifugation is not required. Three types of magnetic particles have been studied in T 4 RIA and the results have been compared with commercial kits and other established methods. (author). 4 refs, 9 figs, 2 tabs

  19. Standardization of the method for measurement of plasma estrone by radioimmunoassay

    International Nuclear Information System (INIS)

    Vilanova, M.S.V.; Moreira, A.C.; Sala, M.M. de; Sa, M.F.S. de

    1994-01-01

    The present paper has as objective standardize a radioimmunoassay method for measurement of plasma estrone. Ethyl ether was used for plasma extraction. The sensitivity (Minimal detectable dose) was 3,7 pg/tube; the reproducibility (inter assay error) was 8,6%; the precision (intra assay error) was 4,1%. As a biological control the plasma estrone was ml) and in 24 patients with polycystic ovarian syndrome (median = 77,9 pg/ml). (author). 6 refs, 2 figs, 2 tabs

  20. An improved radioimmunoassay method for the detection of IgG antibodies against cytomegalovirus

    International Nuclear Information System (INIS)

    Berry, N.J.; Grundy, J.E.; Griffiths, P.D.

    1986-01-01

    The non-specific binding seen with human sera in a radioimmunoassay for the detection of IgG antibodies specific for CMV can be reduced greatly by using a murine monoclonal antibody as a radiolabelled detecting antibody. Such non-specific binding formerly obtained with a polyclonal detecting antibody was due to the binding of the polyclonal reagent to factors on the solid phase other than IgG molecules. (Auth.)