EVALUATION OF THE DOUBLE ANTIBODY RADIOIMMUNOASSAY OF INSULIN AND THE DETERMINATION OF INSULIN IN PLASMA AND URINE IN NORMAL SUBJECTS

1969 ◽  
Vol 60 (2) ◽  
pp. 327-351 ◽  
Author(s):  
Kai R. Jørgensen
Keyword(s):  
Extreme Values ◽  
Degradation Products ◽  
Insulin Response ◽  
Normal Subjects ◽  
Precipitation Reaction ◽  
Fasting Insulin ◽  
Double Antibody ◽  
Insulin In Plasma ◽  
The Subject

ABSTRACT The use of the double antibody method for radio-immunological determination of insulin in plasma was evaluated on the basis of dilution and recovery experiments, as well as by the investigation of the reproducibility and accuracy of the method. Given the optimum conditions for the precipitation reaction, the method appears from the present investigations to be well suited for plasma insulin determinations. With the technique used for the separation of free and antibody bound insulin, the results of the insulin determination were found to be independent of the radioactive degradation products present in the tracer insulin. It was not possible to demonstrate any increased degradation of the tracer insulin by incubation in plasma or urine as compared with incubation in 0.5 % human albumin buffer. The absolute insulin values were found to be independent of the length of the incubation period. No difference was found between the fasting insulin concentrations in a group of new-born infants of non-diabetic mothers and a group of adult normal subjects. Similarly, the fasting insulin values were found to be independent of the sex of the subject investigated. After oral administration of glucose a considerable variation was found in the insulin response in a group of normal subjects. This variation, within the weight limits used, was found to be independent of the sex, age and weight of the subject investigated. A corresponding condition was found to be valid for the insulin excretion in the urine of normal subjects. It was concluded that the large variation in the insulin response in a group of normal subjects did not allow conclusions about the clinical significance of the extreme values, but that the variation alone must be taken as an expression for a pronounced biological variation.

SOME FACTORS OF SIGNIFICANCE IN THE DOUBLE ANTIBODY IMMUNOASSAY OF INSULIN

1967 ◽  
Vol 54 (2) ◽  
pp. 347-361 ◽  
Author(s):  
K. Brunfeldt ◽  
K. R. Jorgensen
Keyword(s):  
Guinea Pig ◽  
Insulin Concentration ◽  
Precipitation Reaction ◽  
Antibody Technique ◽  
Complement Activity ◽  
Double Antibody ◽  
Insulin In Plasma ◽  
Antibody Method ◽  
Heparin Preparation

ABSTRACT Differences were demonstrated between 4 insulin antibody (guinea pig) precipitating antisera (rabbit), int. al. in their ability to cross react with human γ-globulin components. This cross reaction is presumably the reason why »negative« insulin values can be found at higher concentrations of certain precipitating antisera. Independently of the precipitating antiserum it was possible, in some cases, to demonstrate a difference between the insulin concentration in serum and in heparinized plasma. This difference could be eliminated by the addition of heparin, by long-lasting freezing, and by dilution of the serum. Hence, the higher values found in certain cases in serum, as compared with plasma are presumably due to the presence of complement. It is essential in the use of the double antibody technique for the determination of insulin in plasma and serum that a heparin preparation with anti-complement activity should be used and that the concentration range of the precipitating antiserum should be fixed. The double antibody method can be used with or without pre-precipitation if the above mentioned criteria are fulfilled. Pre-precipitation, however, is to be preferred, as the precipitation reaction here occurs under constant conditions.

Enzyme immunoassay of free thyroxin in dried blood samples on filter paper.

1985 ◽  
Vol 31 (5) ◽  
pp. 750-753 ◽  
Author(s):  
N Hata ◽  
K Miyai ◽  
M Ito ◽  
Y Endo ◽  
Y Iijimi ◽  
...  
Keyword(s):  
Enzyme Immunoassay ◽  
Filter Paper ◽  
Room Temperature ◽  
Normal Subjects ◽  
Blood Samples ◽  
Double Antibody ◽  
Coefficients Of Variation ◽  
The Mean ◽  
Measurable Range

Abstract We describe a double-antibody enzyme immunoassay for determination of free thyroxin (FT4) in dried blood samples on filter paper, with use of a T4-beta-D-galactosidase complex. The measurable range of FT4 concentration in two 3-mm blood discs, each of which contained about 2.7 microL of blood, was 1.9 to 93 ng/L, as determined by comparison with concentrations of FT4 in known serum standards. FT4 in blood samples dried on filter paper was stable for at least four weeks when kept dry at -20 degrees C, room temperature, or 37 degrees C. The mean coefficients of variation were 7.6% (within assay) and 6.4% (between assays). Results for FT4 by this method correlated well with those for serum determined by radioimmunoassay (r = 0.98). The proposed method can be used to differentiate persons with hyper- and hypothyroidism from normal subjects and those with abnormal concentrations of thyroxin-binding globulin. The procedure seems suited for screening studies.

scholarly journals Optimisation of the prescription for trans-tibial (TT) amputees

1997 ◽  
Vol 21 (3) ◽  
pp. 168-174 ◽  
Author(s):  
A. Cortés ◽  
E. Viosca ◽  
J. V. Hoyos ◽  
J. Prat ◽  
J. Sánchez-Lacuesta
Keyword(s):  
Quantitative Method ◽  
Clinical Information ◽  
Normal Subjects ◽  
Individual Variability ◽  
Classification Criteria ◽  
The Other ◽  
Human Gait ◽  
Factors Influencing ◽  
The Subject

The great diversity of prosthetic mechanisms available nowadays leads to the question of which type of artificial foot would be the most advisable for a particular person. To answer correctly, it is necessary to establish, in an objective way, the performance of each type of prosthetic mechanism. This knowledge is obtained by means of the study of the subject-prosthesis interaction, both in static and dynamic conditions. This paper, based on the analysis of 8 transtibial (TT) amputees, presents a quantitative method for the study of human gait which allows the determination of the influence of four different prosthetic ankle-foot mechanisms (SACH, Single-axis, Greissinger and Dynamic) on gait. To do this, 1341 gait trials at different cadences were analysed (383 with normal subjects and 958 with amputees, using the four prosthetic feet under study). From all the variables available for study only those which offered interpretable clinical information were chosen for analysis. A total of 18 variables (kinetic, kinematic and time-related) were selected. A covariance analysis (ANOVA) of these variables was made, which showed that the factors influencing TT amputee gait were, in order of importance, cadence and leg studied (sound or prosthetic), inter-individual variability and, finally, the prosthetic mechanism used. When looking at the performance during gait of the 4 prosthetic mechanisms studied it can be observed that there are similarities in the kinetic study between SACH and Dynamic feet on one hand and Single-axis and Greissinger feet on the other. These results seem to support the classification criteria of articulated and non-articulated prosthetic mechanisms.

RADIOIMMUNOASSAY OF GROWTH HORMONE IN HUMAN PLASMA

1972 ◽  
Vol 71 (4) ◽  
pp. 649-664 ◽  
Author(s):  
Kristian F. Hanssen
Keyword(s):  
Growth Hormone ◽  
Human Plasma ◽  
Coefficient Of Variation ◽  
Degradation Products ◽  
Peak Plasma ◽  
Gel Filtration ◽  
Tolerance Test ◽  
Precipitation Reaction ◽  
Insulin Tolerance

ABSTRACT The double antibody radio-immunoassay (pre-precipitation technique) for immunoreactive growth hormone (IRHGH) in human plasma has been evaluated on the basis of dilution and recovery experiments as well as by the investigation of accuracy and reproducibility. Given optimal conditions for the precipitation reaction, the method seems suitable for determination of plasma IRHGH. No cross-reaction between the precipitating antiserum and human gammaglobulin was demonstrated. Furthermore, by using an incubation period of 6 days for the reaction between 125I-HGH and the precipitated HGH antibodies, no serum factor influencing this reaction could be demonstrated. The results of the plasma IRHGH determinations were shown to be independent of the percentage of the radioactive degradation products present in the tracer HGH. The lower detection limit is better than 0.39 ng/ml. The cumulated within-assay coefficient of variation was between 4–7% and the cumulated between-assay coefficient of variation 10%. By using gel filtration, IRHGH in the plasma was shown to be nonhomogeneous when considering molecular weight. The normal fasting values in the ambulatory state was (Mean ± sd) ng/ml: Men 1.48 ± 0.33; women 3.83 ± 3.47. During the insulin tolerance test the mean peak plasma IRHGH was lower in children than in adults (0.02 > P > 0.01). It is suggested that this is due to the influence of sex steroids in adult subjects.

DETERMINATION OF HUMAN GROWTH HORMONE (HGH) IN PLASMA BY A DOUBLE ANTIBODY RADIOIMMUNOASSAY

1966 ◽  
Vol 53 (1) ◽  
pp. 101-120 ◽  
Author(s):  
E. Cerasi ◽  
L. Della Casa ◽  
R. Luft ◽  
A. Roovete
Keyword(s):  
Present Method ◽  
Human Growth ◽  
Antibody Technique ◽  
Double Antibody ◽  
Insulin In Plasma ◽  
Assay Procedure ◽  
Absolute Measure ◽  
Assay Methods ◽  
Per Se

ABSTRACT The double antibody technique of Hales & Randle (1963) for determination of insulin in plasma was developed for the assay of HGH in plasma. The precision and reproducibility of the method as well as the recovery of HGH added to plasma were highly satisfactory. Increased HGH values were obtained in acromegaly and during insulin hypoglycaemia, while decreased values were observed during glucose infusion. Successful treatment of acromegaly was accompanied by the return of plasma HGH levels toward normal. The plasma HGH values obtained with the present method cannot be considered as reflecting the absolute amounts of HGH, since several factors in the assay procedure, mainly the incubation time and the concentration of HGH antibodies used, markedly influenced the values obtained. It is questioned whether the radioimmunological assay methods for HGH per se give an absolute measure of this hormone in plasma.

scholarly journals The variation of the dielectric constants of some organic liquids with frequency in the range 1 to 10 3 Kilocycles

1930 ◽  
Vol 126 (801) ◽  
pp. 213-230 ◽  
Keyword(s):  
Dielectric Constant ◽  
Extreme Values ◽  
Dielectric Constants ◽  
Organic Liquids ◽  
Frequency Range ◽  
Absolute Value ◽  
The Subject ◽  
The Mean ◽  
Made In

Whilst it is recognised that the dielectric constant of liquids changes in the frequency range 10 4 - 10 5 kilocycles per second in accordance with the theory of Debye, no systematic examination of the variation of the dielectric constant of simple liquids with frequency appears to have been made at frequencies below 10 3 kc. per second. Exception must be made of the work of Fricke* who showed that the dielectric constant of blood did not change in the range 0­­­­.8 to 4500 kc., and of that of Bryan who recorded no change in the constant for xylene and an increase in the constant for nitrobenzene in the range 200 to1200 kc. In the case of chloroform and benzene a number of independent determinations have been made, eachat a fixed frequency. The values of the constants, however, at frequencies less than 1000kc. fluctuate considerably, for benzene the divergence between the extreme values is about 2­­·0 percent, of the mean, for chloroform about 12­­·5 percent. It is of importance, therefore, to establish whether these fluctuations are due to experimental error or the variation of the constant with frequency. The experiments now described were planned preliminary to work at higher frequencies; measurements of the dielectric constant and of the conductivity of a number of liquids have been made in the frequency range 1 to 10 3 kc. Attention has been directed to examine the variation of these quantities with frequency rather than to obtain­ing their absolute values. Owing to the illness of one of the authors the work had to be discontinued before the original programme had been completed, nevertheless, in view of the increasing importance of the subject the results appear to be of sufficient interest to merit publication. Since the data now reported were obtained, an extremely careful determination of the absolute value of the dielectric constant for benzene at 1000 cycles has been described by Hartshorn and Oliver ( loc. cit. ). They report no change in the constant in the audio frequency range, that is, presumably, below 5 kc., and thus confirm, in part, the data now presented.

IMPORTANCE OF SOME MOLECULAR MARKERS OF HEMOSTATIC ACTIVATION FOR THE DIAGNOSIS, THE CHOICE AND THE CONTROL OF PREVENTIVE AND CURATIVE THERAPY OF D.V.T. AND P.P.S

1987 ◽  
Author(s):  
M Moriau ◽  
Ch Col-De Beys ◽  
B Golinska ◽  
E Lavenne-Pardonge
Keyword(s):  
Molecular Markers ◽  
Metabolic Disorders ◽  
Extreme Values ◽  
Normal Subjects ◽  
Platelet Inhibitors ◽  
Curative Therapy ◽  
At Iii ◽  
Before And After ◽  
Plasma Factors

The measurement, before and after treatment, of some molecular markers of hemostatic activation (βTG, PF4, TXB2, FPA, 6 keto PGFlα) and the determination of their increased coefficient ratio (Δ+/βTG/Δ+Δ FPA, 4+βTG/4+ PF4,4+ 6 keto PGF1α/Δ+ TXB2 combined with the estimation of other parameters (F.VIII:Ċ/F.VIIIR:AG), AT III, PROT. C, ELT with and without ischemia) permlted us to subdivide the deep venous thromboses in two groupsThe first one or "simple D.V.T." was observed in normal subjects with or without varicoses, and without other main pathology and was consecutive to a simple plasma factors activation, the second one or "complicated D.V.T." appeared in patients with other pathology (infections, neoplasms, trauma, metabolic disorders) and was consecutive to a combined activation of plasma factors and plateletsA:before treat.,B:after anticoagul.,C:after anticoagul. + platelet inhibitors / * extreme values (MV ±2ŊIf anticoagulants (Heparine ancjfor VKA) alone were effective and sufficient for the treatment of "simple DVT" they were little or non active in the "complicated" forms and must be combined with platelet inhibitors to give the same result. The prevention of DVT in venous insuffisancy, consecutive or not to DVT, must be performed in the same way. A comparative study with various types of platelet inhibitors permited us to establish a scale of activity and to observe a benefic synergism with some combinations

Is Quantitative Determination of Fibrin(ogen) Degradation Products and Thrombin-Antithrombin III Complexes Useful to Diagnose Deep Venous Thrombosis in Outpatients?

1989 ◽  
Vol 62 (04) ◽  
pp. 1043-1045 ◽  
Author(s):  
Paul F M M van Bergen ◽  
Eduard A R Knot ◽  
Jan J C Jonker ◽  
Auke C de Boer ◽  
Moniek P M de Maat
Keyword(s):  
Quantitative Determination ◽  
Venous Thrombosis ◽  
Deep Venous Thrombosis ◽  
Antithrombin Iii ◽  
Degradation Products ◽  
Family Doctor ◽  
Diagnostic Value ◽  
Impedance Plethysmography ◽  
Fibrin Degradation Products

SummaryWe studied the diagnostic value of recently introduced ELISA’s for the determination of thrombin-antithrombin III (TAT) complexes, fibrin degradation products (FbDP), fibrinogen degradation products (FgDP) and total degradation products (TDP) for deep venous thrombosis (DVT) in plasma of 239 consecutive outpatients, suspected for DVT by their family doctor. DVT was confirmed by impedance plethysmography in 60 patients. Using the 95th percentile range of 42 healthy volunteers the sensitivity for the detection of DVT was: 37% for TAT, 95% for TDP, 92% for FbDP and 90% for FgDP. Specificity was: 88% for TAT, 16% for TDP, 20% for FbDP and 25% for FgDP.We conclude that these assays are of little value in the diagnosis of DVT in outpatients.

Determination of Factor XIII Activity and of Factor XIII Inhibitors Using an Ammonium-Sensitive Electrode

1983 ◽  
Vol 50 (02) ◽  
pp. 563-566 ◽  
Author(s):  
P Hellstern ◽  
K Schilz ◽  
G von Blohn ◽  
E Wenzel
Keyword(s):  
Factor Xiii ◽  
Normal Subjects ◽  
The Other ◽  
Activity Measurement ◽  
Factor Xiii Deficiency ◽  
Assay Procedure ◽  
Stabilization Factor ◽  
Release Method ◽  
Sensitive Electrode

SummaryAn assay for rapid factor XIII activity measurement has been developed based on the determination of the ammonium released during fibrin stabilization. Factor XIII was activated by thrombin and calcium. Ammonium was measured by an ammonium-sensitive electrode. It was demonstrated that the assay procedure yields accurate and precise results and that factor XIII-catalyzed fibrin stabilization can be measured kinetically. The amount of ammonium released during the first 90 min of fibrin stabilization was found to be 7.8 ± 0.5 moles per mole fibrinogen, which is in agreement with the findings of other authors. In 15 normal subjects and in 15 patients suffering from diseases with suspected factor XIII deficiency there was a satisfactory correlation between the results obtained by the “ammonium-release-method”, Bohn’s method, and the immunological assay (r1 = 0.65; r2= 0.70; p<0.01). In 3 of 5 patients with paraproteinemias the values of factor XIII activity determined by the ammonium-release method were markedly lower than those estimated by the other methods. It could be shown that inhibitor mechanisms were responsible for these discrepancies.

Light Side of Design: Professional Vector

2020 ◽  
pp. 23-33
Author(s):  
Elena A. Zaeva-Burdonskaya ◽  
Yuri V. Nazarov
Keyword(s):  
Professional Practice ◽  
Wide Spectrum ◽  
Scientific Basis ◽  
Design Culture ◽  
Interdisciplinary Nature ◽  
Educational Programmes ◽  
Design Activities ◽  
The Subject ◽  
Light Side

This article addresses one of the most actively developing types of design activities – light design. The article comprises quotes of the leading Russian and foreign light design specialists published over the previous five years, as well as the authors’ own conclusions. The thoughts quoted in the article are sometimes opposite to each other and reflect the wide spectrum of professional practice. They reflect the initial opinions of analysts and experts which are often diverging. All of the specialists point at the interdisciplinary nature of the new profession, which imposes additional load on a designer overloaded enough already by the scope and speed of the problems being solved nowadays. The discussion of the new profession of light designer initiated on the pages of professional publications is especially important in view of the development of professional standards and standards of design and architectural education, as well as creation of new educational programmes based on various approaches to the subject in technical and humanitarian institutions. The goal of this article is to introduce light design into the field of fully legitimate sections of design culture, to define the authentic scientific basis of the new creative profession, to initiate a foundation for self-determination of the new synthetic area, which materially affects the state of the profession as a whole and the life standards of a wide variety of consumers. In order to reach the set goal, a comparative and analytical method of study was selected, which allows studying the problem to a large extent and from all angles and finding the ways of overcoming the challenges emerging in the area of the new activity.

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