Formation and characterization of antibody against 2'-(5"-phosphoribosyl)-5' AMP, the monomer form of poly(adenosine diphosphate ribose).
(17/4669)
Specific antibody against 2'-(5"-phosphoribosyl)-5'AMP (PR-AMP), a monomer of poly(adenosine diphosphate ribose) (poly(ADP-Rib)), was produced by immunizing a rabbit with PR-AMP coupled to bovine serum albumin (BSA). Antibody against PR-AMP was purified 53-fold from serum by (NH4) 2SO4 precipitation, and BSA-Sepharose 4B, DEAE-cellulose and (PR-AMP)-BSA-Sepharose 4B column chromatographies. Inhibition experiments show that the adenine ring, 5'-phosphate residue and ribose-ribose bond of PR-AMP were essential for the antigenic determinant of PR-AMP. Anti PR-AMP antibody bound, not only with PR-AMP, but also with poly(ADP-Rib) of various chain lengths, while anti poly(ADP-Rib) antibody bound with poly(ADP-Rib) but not with PR-AMP. (+info)
Main inhibitor of follicle stimulating hormone in the luteal-follicular transition: inhibin A, oestradiol, or inhibin B?
(18/4669)
The roles of oestradiol, inhibin A and inhibin B in the luteal-follicular transition were assessed by means of specific assays. Six premenopausal women were studied during a control and then a cycle treated with percutaneous oestradiol 0.1 mg/day from day 10 after the luteinizing hormone (LH) surge until day 4 of the following cycle. Inhibin A concentrations decreased similarly in control and treated cycles from day -5 to day 2, then increased in control cycle to 23.3 +/- 3.4 pg/ml on day 10 (mean +/- SEM). They remained low until day 5 in treated cycles and were lower than controls on day 10 (P < 0.01). Follicle stimulating hormone (FSH) concentrations increased on day 1 in controls and on day 5 in treated cycles when oestradiol concentration fell abruptly. Inhibin B concentrations remained low until day 1 in controls and day 4 in treated cycles. In both, inhibin B concentrations increased 1 day after FSH, peaking at 160 pg/ml. FSH concentrations began to plateau when inhibin B concentrations were >100 pg/ml and oestradiol concentrations below 200 pmol/l. These data suggest that inhibin A is not responsible for FSH suppression in the luteal phase and that the negative control of FSH shifts from oestradiol in the luteal phase to inhibin B in the mid-follicular phase. (+info)
Evaluation of the ImmunoCardSTAT! rotavirus assay for detection of group A rotavirus in fecal specimens.
(19/4669)
Rapid detection of group A rotavirus was performed by using ImmunoCardStat! Rotavirus (ICS-RV) (which uses immunogold-based, horizontal-flow membrane technology), two commercial enzyme immunoassays (Premier Rotaclone and TestPack Rotavirus), and electron microscopy. A total of 249 stool specimens collected from children with gastroenteritis between February and April 1997 were tested. After resolution of 19 of the 22 discordant results by reverse transcription-PCR for group A rotavirus, ICS-RV detected 125 positives while Rotaclone and TestPack detected 127 and 129 positives, respectively. The sensitivity, specificity, positive predictive value, and negative predictive value were 94.0, 100, 100, and 93.4% for ICS-RV; 95.5, 100, 100, and 95.0% for Rotaclone; and 97.0, 96.5, 97.0, and 96.5% for TestPack. ICS-RV was sensitive and specific and was relatively simple to perform and interpret. (+info)
Immunochromatography test for rapid diagnosis of adenovirus respiratory tract infections: comparison with virus isolation in tissue culture.
(20/4669)
The sensitivity and the specificity of a new commercial rapid 10-min adenovirus antigen immunochromatography (IC) test were determined by comparison with the sensitivity and specificity of virus isolation. Of 169 pharyngeal swabs from children with suspected adenovirus respiratory tract infections, 95 (56%) were culture positive for adenovirus. The IC test was sensitive (detecting 69 of these 95 infections [72.6%]) and completely specific (identifying 74 of 74 specimens [100%]) when it was compared with cell culture. The test detected adenovirus serotypes 1, 2, 3, 5, and 7 with almost equal sensitivities. This test is not only rapid and easy to perform but also sensitive and specific for adenovirus respiratory tract infections. The test is sufficiently rapid to be used at the bedside or in an outpatient clinic, with the result being available during a patient's first examination. (+info)
B-Cell coactivator OBF-1 exhibits unusual transcriptional properties and functions in a DNA-bound Oct-1-dependent fashion.
(21/4669)
Eukaryotic transcriptional activators generally comprise both a DNA-binding domain that recognizes specific cis-regulatory elements in the target genes and an activation domain which is essential for transcriptional stimulation. Activation domains typically behave as structurally and functionally autonomous modules that retain their intrinsic activities when directed to a promoter by a variety of heterologous DNA-binding domains. Here we report that OBF-1, a B-cell-specific coactivator for transcription factor Oct-1, challenges this traditional view in that it contains an atypical activation domain that exhibits two unexpected functional properties when tested in the yeast Saccharomyces cerevisiae. First, OBF-1 by itself has essentially no intrinsic activation potential, yet it strongly synergizes with other activation domains such as VP16 and Gal4. Second, OBF-1 exerts its effect in association with DNA-bound Oct-1 but is inactive when attached to a heterologous DNA-binding domain. These findings suggest that activation by OBF-1 is not obtained by simple recruitment of the coactivator to the promoter but requires interaction with DNA-bound Oct-1 to stimulate a step distinct from those regulated by classical activation domains. (+info)
Glomerular and tubular proteinuria as markers of nephropathy in rheumatoid arthritis.
(22/4669)
OBJECTIVE: We examined the prevalence of nephropathy in unselected patients with rheumatoid arthritis (RA) by measurement of marker proteins for glomerular and tubular damage in urine. METHODS: A highly sensitive immunoluminometric assay was used to measure albumin, immunoglobulin G and alpha1-microglobulin in 24 h urines of 44 RA patients and a control group of 46 patients with generalized osteoarthritis (OA). RESULTS: Fifty-five per cent of RA patients were found to have proteinuria as a symptom of renal disease. Drug therapy or vasculitis were identified as possible reasons for proteinuria in only 25% of these patients; in most patients (75%), no reason for proteinuria was found. Tubular and mixed proteinuria were more frequent than glomerular proteinuria. Only 15% of the control group exhibited mild proteinuria, which was attributable to nephrotoxic factors. The renal function of RA patients and the control group did not differ significantly. CONCLUSIONS: Proteinuria is a frequent symptom of nephropathy in RA. Screening for renal disease in RA should not only include creatinine measurement and dipstick examination of urine, but also more sensitive methods to detect tubular and glomerular proteinuria as a marker of tubular and early stages of glomerular damage. (+info)
Comparison of free and peptide-bound pyridinoline cross-links excretion in rheumatoid arthritis and osteoarthritis.
(23/4669)
OBJECTIVE: To investigate urinary fractions of free and peptide forms of pyridinoline cross-links in arthritis. PATIENTS AND METHODS: The free and total forms of pyridinoline (Pyr) and deoxypyridinoline (Dpyr) were measured by high-performance liquid chromatography (HPLC) in 30 pre-menopausal and 22 post-menopausal normal women, 38 women with rheumatoid arthritis (RA) and 62 women with osteoarthritis (OA). Peptide forms were calculated as total minus free. Free Dpyr and peptide form were also measured by deoxypyridinoline and carboxy-terminal telopeptide of type I collagen (CTx) immunoassays. RESULTS: In normal women, all fractions of Pyr and Dpyr and immunoassays were elevated in post-menopause compared to pre-menopause. In post-menopausal normal women, the free form increased more than the peptide form. In RA, an increase in the fractions of Pyr was greater than Dpyr. Peptide and total cross-links correlated with the disease activity of RA and they were elevated in RA patients with high disease activity. Free Dpyr and CTx were significantly lower in OA than in normal women. Peptide and total Pyr and Dpyr, and immunoassayed Dpyr were significantly higher in the radiographic later stage of OA than in the early stage of OA. CONCLUSIONS: The menopause, RA and OA may have different effects on the urinary excretion of free and peptide-bound pyridinoline cross-links. (+info)
Development of an ultrasensitive immunoassay for human glandular kallikrein with no cross-reactivity from prostate-specific antigen.
(24/4669)
BACKGROUND: Studies demonstrating that human glandular kallikrein (hK2) is increased in prostate cancer patients have prompted speculation that this marker may of use in addition to prostate-specific antigen (PSA). METHODS: An ultrasensitive hK2 sandwich immunoassay was developed, and its detection limit, cross-reactivity, analytical recovery, precision, and linearity of dilution were evaluated. hK2 was measured in seminal plasma and sera from healthy males, females, and prostatectomized patients. RESULTS: Our assay has an excellent detection limit (6 ng/L) and precision (>90%). Recovery studies indicated that hK2 binds to serum protease inhibitors. All sera from healthy males had measurable hK2 concentrations (median, 402 ng/L). Almost all female sera had undetectable hK2. Serum hK2 and PSA in males correlated positively (r = 0.44), but hK2 was present at concentrations approximately 2. 5-fold lower than PSA. The PSA/hK2 ratio in male sera was 0.1-34, with a median of 2.6. In seminal plasma, this ratio was 100-500. More than 94% of immunoreactive hK2 in serum was in the free form ( approximately 30 kDa); traces of hK2 complexed to alpha1-antichymotrypsin were present. CONCLUSIONS: The limit of detection of the method for hK2 measurement described here ( approximately 20-fold lower than any other reported assay for hK2) allows the generation of new clinical information. When combined with a previously described method for PSA measurement that has no cross-reactivity from hK2, this methods allows the relative proportions of hK2 and PSA in biological fluids to be measured. (+info)