An enzyme-immunoassay for estriol.

A practical method was developed for enzyme-immunoassay of serum estriol, with alkaline-phosphatase as a marker enzyme. Alkaline-phosphatase was conjugated with estriol-6-(O-carboxymethyl) oxime using water soluble carbodiimide. The estriol-alkaline-phosphatase complex, which has both enzyme activity and capacity to bind anti-estriol serum, was obtained by Sephadex G-200 gel filtration. This complex, which was stable for at least 3 months at 4 degrees C, was used as enzyme-labelled estriol. Anti-estriol serum raised against estriol-6-(O-carboxymethyl) oxime bovine serum albumin was employed. "Bound and free" estriol were separated by the double antibody method. A linear relation was obtained between estriol concentration and antibody-bound alkaline-phosphatase activity in the range of 0.2-100 ng estriol/ml. In this assay system, cross-reactivity with other steroids was negligible under physiological conditions, and endogenous alkaline-phosphatase, which increases during the late pregnancy, caused no interference. The coefficients of variation were 3.3-14.2% (within assays), and less than 22% (between assays), and the mean recovery rate was 77.5%. Serum estriol values determined by the present method correlated well with those determined by radioimmunoassay (r=0.90 for total estriol; r=0.98 for free estriol). The present method of enzyme-immunoassay is suitable for measurement of serum estriol during pregnancy.     

Changes in estrogen levels in maternal venous plasma after intra-amniotic infusion of prostaglandin F2 for therapeutic abortion

Peripheral plasma levels of estrone, estradiol-17beta and estriol were measured by the method of Shutt and Cox in 10 women following intra-amniotic infusion of prostaglandin F2alpha (PGF2a) for therapeutic abortion. Initial dose was 30 mg, followed if necessary, by doses of 15 mg at 24 hours and 42 hours. Gestational age of pregnancies ranged from 14 to 19 weeks, with a mean of 16 weeks. All 10 women completely aborted. Mean induction-abortion interval was 24 + or - 12 hours. The mean estrone, estradiol 17beta and estriol levels declined to about half of the pre-infusion levels after 80% of the induction-abortion interval had elapsed. The main decline in estrogen levels occurred in individual women either during the 1st quarter or during the last quarter of the induction-abortion interval. There were no significant relationships between changes in estrogen levels and the interval from 1st administration of PGF2a to subsequent abortion.     

Plasma estriol levels after intramuscular injection of estriol and two of its esters

Twelve female volunteers from Berlin and 9 from Stockholm, all using a contraceptive pill (30 micrograms ethinyl estradiol and 150 micrograms levonorgestrel), received an intramuscular injection of estriol (E3; 1 mg in oil) on day 5 of withdrawal bleeding. Blood samples were collected at increasing time intervals during 4 weeks. Three months later, on day 5 of their withdrawal bleeding, 6 women were given intramuscularly (in oil) estriol 3,17-dipropionate (E3-prop) and 15 women estriol 3,17-dihexanoate (E3-hex). The doses were equivalent to 5 mg of estriol, i.e. 6.94 and 8.90 mg, respectively. Blood samples were collected during a period of 9 weeks. Estriol was analyzed by radioimmunoassay in all plasma samples. The average half-life of E3 ranged from 1.5 to 5.3 h after the administration of E3. It was 12.7 h and between 187 and 221 h after the administration of E3-prop and E3-hex, respectively. The average areas under the curve (in nmol.l-1.h) of E3 were between 82.5 and 161 after the administration of E3-prop or E3-hex, and between 27.1 and 37.9 when E3 had been given. As E3 was administered in a 5-fold lower dose than the esters, the areas under curve appeared to be comparable. Thus, the total exposure to E3 seemed to be almost independent of the type of E3 derivatization, while the time and intensity of exposure were very different.     

Measurement of salivary resistin, visfatin and adiponectin levels

Hormonal determination in saliva offers several advantages. Peptides enter the salivary glands either by active transport mechanisms or are expressed and secreted by the salivary glands themselves. The collection of saliva is a noninvasive, easily repeatable and less stressful technique than blood withdrawal. The purpose of the present study was to introduce a method for measuring salivary resistin, visfatin and adiponectin levels and to evaluate their associations with serum levels. Resistin, visfatin and adiponectin levels were measured in serum and saliva of 50 healthy adult volunteers (17 male and 33 female) using commercial enzyme immunoassay kits for serum with minor modifications. The present study documented the determination of resistin and adiponectin levels in saliva and the significant correlation of salivary levels with serum levels (r=0.441, p<0.01 and r=0.347, p<0.05, respectively). Moreover, the identification of visfatin in saliva was achieved, but no significant correlation with serum visfatin levels was observed. To our knowledge, this is the first study to report the determination of resistin and visfatin in saliva and the significant correlation of salivary resistin with serum levels, while it confirmed the significant association between salivary and serum adiponectin. The introduction of salivary determinations of adipokines could contribute to the elucidation of the physiology and the role of the specific adipokines in various clinical conditions (obesity, insulin resistance, inflammation, reproduction, energy imbalance and stress response).     

Elisa for salivary and plasma estriol in pregnancy

A competitive, sensitive, and rapid enzyme-linked immunoadsorbent assay (ELISA) was developed for the determination of estriol in saliva and in plasma. Horseradish peroxidase (HRP) was used as the label enzyme; separation between free and bound steroid was carried out by insolubilized antibody prepared by adsorbing purified IgG of rabbit anti-6-oxoestriol-6-(0-carboxymethyl)oxime-BSA on polystyrene balls. The enzyme activity was measured by a colorimetric reaction using o-phenylenediamine dihydrochloride and hydrogen peroxide as substrate. The sensitivity of the assay was 12 pg/tube.In order to compare ELISA to RIA estriol estimations in different biological fluids, we selected six women during normal pregnancy, from the 30th to the 40th week of gestation. Salivary estriol was assayed by direct and extraction methods, while the corresponding plasma samples of the same subjects were analyzed only for unconjugated estriol by an extraction method.A good agreement was found between the results obtained by RIA and ELISA: r=0.897, p <0.001 between direct RIA and direct ELISA in saliva; r=0.909, p < 0.001 between extraction RIA and direct ELISA in saliva; and r=0.916, p < 0.001 between extraction RIA and extraction ELISA in plasma. A good correlation (r=0.793, p<0.001) was present between plasma samples by RIA and saliva samples by ELISA (direct method).These results indicate that: 1. ELISA is a reliable method for the determination of estriol in plasma and saliva. 2. Saliva samples can be used for the assay of estriol and therefore for the assessment of fetal conditions during pregnancy.     

A sephadex column radioimmunoassay of unconjugated estriol in pregnancy plasma

A rapid, precise, and accurate radioimmunoassay for unconjugated estriol in pregnancy plasma has been developed which makes use of the adsorptive properties of Sephadex. The estriol is extracted from plasma by adsorption onto a small column of Sephadex. After the proteins and other interfering materials are washed away, the estriol is equilibrated with a limiting amount of specific antibody. The Sephadex column serves as a means of separating the bound from the unbound estriol, the ratio of which is determined by adding to the system tracer amounts of tritium labeled hormone. The sensitivity is about 220 pg in the sample. The intra- and inter-assay coefficient of variation is 5–6%. The method correlated well with one which involved purification of the estriol prior to quantitationby radioiommunoassay.     

A comparison of ghrelin, glucose, alpha-amylase and protein levels in saliva from diabetics

During the past decade, many salivary parameters have been used to characterize disease states. Ghrelin (GAH) is recently-discovered peptide hormone secreted mainly from the stomach but also produced in a number of other tissues including salivary glands. The aim of this work was to examine the relationship between active (aGAH) and inactive (dGAH) ghrelin in the saliva and other salivary parameters in type II diabetic patients and healthy controls. Salivary parameters were assessed in a single measurement of unstimulated whole saliva from 20 obese and 20 non-obese type II diabetes patients, and in 22 healthy controls. Total protein and alpha-amylase were determined by colorimetric methods, and glucose by the glucose-oxidase method. Saliva aGAH and dGAH levels were measured using a commercial radioimmunoassay (RIA) kit. Salivary concentrations of aGAH and dGAH ghrelin were more markedly decreased in obese diabetic subjects than in the two other groups. Glucose and alpha-amylase levels were higher in diabetic subjects than in controls. Furthermore, there were correlations between GAH levels and BMI, and between GAH and blood pressure. However, there was no marked variability in saliva flow rates among the groups. These results indicate that measurement of salivary GAH and its relationship to other salivary parameters might help to provide insight into the role of ghrelin in diabetes.     

Effect of dextran-coated charcoal on radioimmunoassays of unconjugated estriol in serum

Lipid interference in the radioimmunoassay of steroids can cause an apparent variation in post-prandial serum concentrations of unconjugated estriol. The effects of increased concentrations of dextran-coated charcoal (15--60 g/l) in the radioimmunoassay of estriol standards with and without triglycerides were studied. All concentrations of dextran-coated charcoal used in this study eliminated the previously observed effects of estriol-lipid partitioning. When we used similar concentrations of dextran-coated charcoal, we found that serum cortisol levels in pregnant women declined significantly during the day (P less than 0.001), but no significant variation in estriol concentrations was observed. These results indicate that the previously reported diurnal variation in serum unconjugated estriol concentrations attributed to steroid-lipid partitioning can be eliminated by increasing the concentration of dextran-coated charcoal in assays using this method of separation.     

A comparative study of the effect of 17β-estradiol and estriol on peripheral pain behavior in rats

Although estradiol has been reported to influence pain sensitivity, the role of estriol (an estradiol metabolite and another widely used female sex hormone) remains unclear. In this study, pain behavior tests, whole-cell patch clamp recording and Western blotting were used to determine whether estriol plays a role in pain signal transduction and transmission. Either systemic or local administration of 17β-estradiol produced a significant rise of mechanical pain threshold, while estriol lacked this effect in normal and ovariectomized (OVX) rats following estriol replacement. Local administration of 17β-estradiol or estriol significantly decreased ATP-induced spontaneous hind-paw withdrawal duration (PWD), which was blocked by an estrogen receptor antagonist, ICI 182, 780. However, systemic application of estriol in normal or OVX rats lacked this similar effect. In cultured dorsal root ganglion neurons, estriol attenuated α,β-methylene ATP-induced transient currents which were blocked by ICI 182, 780. In complete Freund's adjuvant treated (CFA) rats, systemic application of 17β-estradiol or estriol decreased the mechanical pain threshold significantly, but did not change the inflammatory process. Similar effects were observed after estriol replacement in OVX rats. The expression of c-fos in lumbosacral spinal cord dorsal horn (SCDH) was increased significantly by administration of 17β-estradiol but not estriol, and not by estriol replacement in OVX rats. These results suggest that 17β-estradiol but not estriol plays an anti-hyperalgesic role in physiological pain. However, both peripheral 17β-estradiol and estriol play anti-hyperalgesic roles in ATP-induced inflammatory pain. Systemic application of estriol as well as 17β-estradiol plays hyperalgesic roles in CFA-induced chronic pain.     

A rapid specific radioimmunoassay for unconjugated estriol in plasma.

A rapid, non-chromatographic radioimmunossaay for unconjugated estriol in pregnancy plasma has been developed which utilizes a commonly available antiestrogen antisera. Estradiol-17beta and estrone demonstrate 135% relative cross-reactivity with our antiserum, as compared with 100% for estriol. Specificity is achieved by purification of estriol with solvent partitioning using benzene: petroleum ether (1:1). The results obtained using this method are similar to a radioimmunoassay utilizing a highly specific, but commercially unavailable, antiestriol antiserum. The method is precise, with coefficients of variation ranging from 3.0 to 8.2%.     

Rapid enzyme hydrolysis of urine extracts for estriol analysis.

A method is described for quantitatively hydrolyzing estriol glucosiduronate (and presumably other urinary steroid glucosiduronates and sulfates) in 2 hr after concentration of the urine and removal of enzyme inhibitors by passage over a column of XAD-2 resin. The estriol is sufficiently pure for direct GLC or mass spectrometry analysis.     

Music stimuli lead to increased levels of nitrite in unstimulated mixed saliva

Concentration of salivary nitrate is approximately 10-fold to that of serum. Many circumstances such as acute stress could promote salivary nitrate secretion and nitrite formation. However, whether other conditions can also be used as regulators of salivary nitrate/nitrite has not yet been explored. The present study was designed to determine the influence of exposure to different music on the salivary flow rate and nitrate secretion and nitrite formation. Twenty-four undergraduate students(12 females and 12 males) were exposed to silence, rock music, classical music or white noise respectively on four consecutive mornings. The unstimulated salivary flow rate and stimulated salivary flow rate were measured. Salivary ionic(Na+, Ca2+Cl-,and PO3-4) content and nitrate/nitrite levels were detected. The unstimulated salivary flow rate was significantly increased after classical music exposure compared to that after silence. Salivary nitrite levels were significantly higher upon classical music and white noise stimulation than those under silence in females. However, males were more sensitive only to white noise with regard to the nitrite increase. In conclusion, this study demonstrated that classical music stimulation promotes salivary nitrite formation and an increase in saliva volume was observed. These observations may play an important role in regulating oral function.     

Direct determination of estriol 3- and 16-glucuronides in pregnancy urine by column-switching high-performance liquid chromatography with fluorescence detection

An HPLC method for the direct and simultaneous determination of estriol 3- and 16-glucuronides in pregnancy urine is described. The method is based on direct derivatization of the glucuronic acid moiety in estriol glucuronides in urine with 6,7-dimethoxy-1-methyl-2(1H)-quinoxalinone-3-propionylcarboxylic acid hydrazide. The derivatization reaction proceeds in aqueous solution (or urine sample) in the presence of pyridine and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide at 37°C. The resulting fluorescent derivatives were separated by column-switching chromatography using a first column (YMC-Pack C₄) for clean-up of the derivatives and a second column (YMC Pack Ph) for the complete separation of the derivatives. The derivatives were detected spectrofluorimetrically at 445 nm with excitation at 367 nm. The detection limits (signal-to-noise ratio=3) for estriol 3- and 16-glucuronides were 150 and 180 fmol in a 5 μl of urine (14 and 17 ng ml⁻¹ urine), respectively. The present method is highly sensitive and simple without any clean-up such as conventional solid-phase extraction.     

Salivary immunoglobulin A levels in rapid and slow plaque formers: a pilot study

The aim of this study was to investigate the salivary immunoglobulin A concentration in rapid and slow plaque formers. After 3 days of oral hygiene abstinence, 49 healthy volunteers were screened using the plaque index (PI) to assess their plaque formation rates. Five subjects with the highest, and five with the lowest mean PI were selected as rapid and slow plaque formers, respectively. Unstimulated whole saliva was collected from each of these ten subjects and the levels of salivary IgA assessed using a conventional ELISA technique. Reference curves for salivary IgA were established by testing serial dilutions of human IgA with known concentrations. When the differences between the two groups were compared, almost a twofold increase in the mean salivary IgA concentration in the slow (16 microg/ml +/- 4) compared with the rapid (9 microg/ml +/- 3) plaque formers was recorded (p < 0.05). These findings, reported for the first time, imply that salivary IgA may play a crucial role in regulating the pioneer plaque development on enamel surfaces.     

Responses of salivary cortisol levels to stress-situations

A procedure is described for determining salivary cortisol levels by a competitive protein-binding assay using horse transcortin. The collection of saliva was performed by means of filter paper-strips. Filter paper samples are more than 5 days stable after air-drying. In this form, the samples could be stored without refrigerator or deep-freezer and, if necessary, sent by post to the laboratory without any special precaution. Stressful situation of either painful or anxious origin were associated with an adequate increase of salivary cortisol levels. The increases were 157 to 230% of the initial or normal values dependent on the kind of stress. The mean values in 4 cases of Cushing's syndrome were 380% and 1 hour after 25 I.U. ACTH 690% higher than those in normal persons. In normal persons, a well-defined circadian rhythm has been observed.     

Effect of calcium on in vitro contractility of human umbilical artery

The action of calcium on human umbilical artery was studied by an in vitro perfusion method. An increase in tonus and intense spontaneous activity were observed in the preparations at high calcium concentrations. A marked relaxation of the umbilical artery occurred in the absence of calcium. Estriol had a relaxing effect on the umbilical vessels which was more intense at calcium concentrations near physiological levels. Estriol also abolished spontaneous contractions. In the absence of calcium, estriol showed no relaxing effect. The results suggest a participation of calcium in the mechanism of action of estriol on human umbilical artery in vitro.     

16-sulfates of estriol in body fluids of human pregnancy at term.

A method was developed for the assay of estriol-16-sulfate (E3-16S) and estriol-3, 16-disulfate (E3-3,16-diS) in maternal serum, cord serum and amniotic fluid at delivery in human pregnancy. Tritiated E3-16S and E3-3,16-diS are added to the fluid being analyzed. The conjugates are separated and purified by sequential chromatography on alumina, Celite and Sephadex LH-20. Each conjugate is hydrolyzed with Glusulase and the released estriol is quantified by radioimmmunoassay. E3-3,16-diS was found in each fluid, most concentrated in the cord serum. Small amounts of E3-16S were found in some amniotic fluids, and this conjugate was virtually absent from the sera. These new estriol conjugates comprise less than 1 percent of total, estriol, apparently too low to be of diagnostic value in human pregnancy.     

Serum and salivary levels of albumin as diagnostic tools for oral pre-malignancy and oral malignancy

The role of oxygen free radicals in the initiation, promotion and progression of carcinogenesis and the protective role of antioxidants has been a subject of much speculation. There are few studies that report evaluation of serum albumin and only one study in which salivary albumin was found and only one study that reports of salivary albumin in oral Leukoplakia and Oral Squamous Cell Carcinoma (OSCC). We evaluated serum and salivary albumin levels in normal individuals, patients with oral pre-malignancy and patients with oral malignancy, and we compared serum and salivary albumin levels in patients with oral pre-malignancy and oral malignancy. Our study comprised 45 subjects separated into three groups of 15: normal healthy, oral pre-malignancy and oral malignancy patients. Venous blood was drawn and unstimulated saliva was collected early in the morning. Albumin levels were estimated using the bromocresol green method. Serum albumin levels decreased in oral pre-malignancy and oral malignancy cases compared to healthy individuals. Salivary albumin levels increased in oral pre-malignancy and oral malignancy cases compared to healthy individuals. Our results suggest that albumin may play a role in early diagnosis and prognosis of oral pre-malignant and oral malignant tissues.     

Simultaneous determination of adreno-ovarian steroids from a single aliquot

A standardized technique for simultaneous fractionation and estimation of samples of progesterone, estrone, 17alpha-estradiol, 17beta-estradiol, estriol, corticosterone, cortisone, and cortisol obtained from guinea-pigs during mid-pregnancy is presented. The hormones were separated on a single TLC plate using a single solvent system, and were measured on a single biphasic column on the basis of a single aliquot. The technique affords considerable utility in the inves tigation of the complexities of the adreno-genital syndrome. Progesterone content in the ovaries and plasma showed an increase of 77% during pregnancy, while plasma levels of estrone were increased by 34%. Urinary estradiol levels were also markedly increased. Plasma estradiol and estriol and placental estriol could not be detected by the technique. Adrenal cortisone levels and plasma cortisone and cortisol were considerably higher during pregnancy. An initial overlap was found between cortisol and estriol on the TLC plate, though subsequent estimation by GLC overcome the problem.     

Improved strategy for biosensor-based monitoring of water bodies with diverse organic carbon levels

To protect water resources and to control the water quality it is necessary to develop fast, sensitive, cost-effective, and easy-to-use analytical systems, which are able to measure a variety of contaminants in water. Monitoring water bodies with various matrices can be very difficult. The diverse organic carbon level in water samples (e.g. river water or seawater) causes problems at common analysis and in particular at immunological methods. Here, we demonstrate a new method to overcome the partly occurring matrix problems at quasi-continuous real-world biosensor monitoring. Therefore, we developed an easy matrix referencing method for our fully automated immunoassays that could be adapted to other applications depending on a similar test-format. The method was developed using a synthetic organic carbon standard, and validated using a diluted turf extract. Results for the ultra-sensitive immunoassay for estrone quantification are shown as example. The developed method was verified using immunoassays for testosterone, progesterone, ethinylestradiol, estradiol, and estriol.