Search results for "Radioimmunoassay"

Preliminary Findings: 25(OH)D Levels and PTH Are Indicators of Rapid Bone Accrual in Pubertal Children

2007

The objective of this study was to evaluate the role of serum levels of 25(OH)D and PTH on the accumulation of whole body bone mass in a cohort of children.This was a longitudinal study (1.98 +/- 0.07 y) of sixty-nine children (89% Caucasian, 44% male) enrolled in a calcium supplementation trial. Bone area, bone mineral content (BMC) and density (BMD) of the whole body and radius were assessed using a QDR 2000 (Hologic, Inc) dual energy x-ray absorptiometer. Serum PTH and 25(OH)D were measured using radioimmunoassays.Vitamin D stores were inversely related gain in bone area (p0.002), BMC (p0.002) BMD (p0.027), as well as to PTH levels (p0.0001). Compared to those with adequate vitamin D sto…

PE-11, a peptide derived from chromogranin B, in the rat eye.

2010

The aim of the study was to investigate the presence and distribution of PE-11, a peptide derived from chromogranin B, in the rat eye. For this purpose, newborn rats were injected with a single dosage of 50mg/kg capsaicin subcutaneously under the neck fold and after three months, particular eye tissues were dissected and the concentration of PE-11-like immunoreactivity was determined by radioimmunoassay. Furthermore, PE-11-like immunoreactivities were characterized in an extract of the rat eye by reversed phase HPLC. Then, the distribution pattern of PE-11 was investigated in the rat eye and rat trigeminal ganglion by immunofluorescence. As a result, PE-11 was present in each tissue of the …

Effect of circulating growth hormone on muscle IGF-I protein concentration in female mice with growth hormone receptor gene disruption.

2009

Growth hormone (GH) is a potent secretague for circulating insulin-like growth factor-I (IGF-I). The purpose of this study was to examine the effect of circulating GH on muscle IGF-I protein expression using GH transgenic animal models. Three different models were used: mice that overexpress bovine GH (bGH; n=10), mice without a functional GH receptor (GHR-/-; n=10), and wildtype mice (n=10). All mice were 16-week old females and each group differed in their basic phenotypic characteristics. Immediately after euthanization the triceps surae muscle group (soleus, plantaris, and gastrocnemius muscles) was removed. IGF-I was extracted from the muscle with an acid-ethanol solution (12.5% 2N hyd…

Evidence for the neuronal origin of immunoreactive interleukin-1 beta released by rat hypothalamic explants.

1996

In this study, we have investigated the release of immunoreactive interleukin-1 beta (irIL-1 beta) from the rat hypothalamus in vitro. It was found that (1) tissue explants release sizable amounts of irIL-1 beta (ranging from 0.43 to 0.52 pg/mg of wet tissue) in 20 min incubations; (2) basal release in significantly increased by depolarization induced with 56 mM KCl; (3) K(+)-induced irIL-1 beta release is inhibited by the specific blocker of N-type calcium channels, omega-conotoxin, and by verapamil, but not by nifedipine; (4) K(+)-induced release is also inhibited by the Na+ channel blockers tetrodotoxin and lidocaine; (5) irIL-1 beta release is significantly increased by noradrenalin; su…

Formation and metabolism of catecholestrogens in depressed patients.

1990

Abstract The evidence that catecholestrogens are formed in the brain and exert behavioral effects in animal models suggests that these steroids might have psychotropic activities. In the present investigation, the formation and metabolism of catecholestrogens were studied in depressed patients. Twenty-four-hr urine samples were collected from 6 male patients (59 ± 8 years) with endogenous retarded depression (subtype primary, endogenous, and recurrent according to Research Diagnostic Criteria) and from 12 male control subjects (51 ± 4 years). The patients were treated with the monoamine oxidase inhibitor tranylcypromine (10–40 mg/day for 3–4 weeks). The concentrations of primary estrogens, …

Enhanced serum levels of soluble HLA class I molecules are induced by treatment with recombinant interferon-gamma (IFN-γ)

1991

SUMMARY In order to investigate serum levels of soluble HLA class I antigens after single injection of various doses of recombinant IFN-γ (rIFN-γ) and to correlate the changes observed to beta-2-microglobulin serum levels, we studied five patients with metastasizing renal cell carcinoma. Each patient received three treatment cycles of 10, 100 and 500 μg rIFN-γ three times at weekly intervals. The treatment cycles were separated by a therapy-free interval of 2 weeks. The order of dose levels was randomly assigned to each patient. Serum levels of soluble HLA class I proteins were measured by an ELISA in samples drawn immediately before and 4, 24, 48, 72 and 168 h after each administration of …

Methodology and significance of the detection of liver-kidney-microsomal (lkm) autoantibodies in autoimmune-type chronic active hepatitis

1987

Liver-kidney-microsomal (LKM) autoantibodies are diagnostic markers for a subgroup of HBsAg-negative chronic active hepatitis, presumably owing to autoimmunity. They were originally detected by indirect immunofluorescence and can now be evaluated by radioimmunoassay, enzyme-linked immunosorbent assay, and immunoblotting. In immunoblotting LKM-positive sera react strongly with a 50-kilodalton (KD) polypeptide band of microsomes. In immunoelectron microscopy, LKM-positive sera show a binding with membranes of the endoplasmic reticulum. The LKM antigen was further identified on various isoenzymes of cytochrome P-450. Immunofluorescence is still the method of choice for screening sera routinely…

Radioimmunoassay of Plasma and Urinary Norepinephrine

1989

Various analytical methods, such as fluorimetry, radioenzymic assay and in particular liquid chromatography are used for the analysis of norepinephrine (NA) in body fluids and tissue homogenates. These procedures, however, often lack sensitivity, are expensive and/or time consuming. Basing on our previous reports on the radioimmunoassay of chemically modified serotonin1, 5-hydroxy-3-indole acetic acid2 and normetanephrine (NMN)3, a sensitive radioimmunoassay of the N-acetyl,3-methoxy analogue of urinary and plasma norepinephrine was developed.

Anti-Endothelzell-Antikörper

2008

In vitro secretion of specific antimitochondrial antibodies in primary biliary cirrhosis

1992

Antimitochondrial antibodies are present in the serum of virtually all patients with primary biliary cirrhosis. They have a well-defined antigen reactivity that is diagnostic for the disease. The role of these autoantibodies in the disease process remains to be defined. In this study we show that antimitochondrial antibodies can be produced in vitro by peripheral blood lymphocytes, that the cells producing antimitochondrial antibodies are present in the peripheral blood in a high frequency and seem to be maximally activated. Stimulation with pokeweed mitogen did not augment the in vitro production of antimitochondrial antibodies in patients nor did it induce the production of these antibodi…