Sensitive time-resolved immunofluorometric assay of thyrotropin in serum

We have developed a time-resolved solid-phase immunofluorometric assay for thyrotropin (TSH). The assay is performed in white opaque microtitration wells which are coated with a monoclonal capture antibody. Serum TSH binds simultaneously to the solid phase and to a biotinylated monoclonal detection antibody. The degree of biotinylated antibody binding is quantitated with streptavidin conjugated to thyroglobulin which is heavily labelled with the Eu3+ chelator 4,7-bis [chlorosulfophenyl] -1,10-phenanthroline -2,9-dicarboxylic acid (BCPDA). The final fluorescent complex is measured on the solid phase with time-resolved fluorometry. The assay requires two incubation steps and can be completed in 5 hours. The detection limit is 0.03 milli-int. units/L. The present assay was compared with two immunoradiometric assays and gave satisfactory results.     

Caveolin-3 in muscular dystrophy

The dystrophin-glycoprotein complex (DGC) serves as a link between cytoplasmic actin, the membrane and the extracellular matrix of striated muscle. Genetic defects in genes encoding a subset of DGC proteins result in muscular dystrophy and a secondary decrease in other DGC proteins. Caveolae are dynamic structures that have been implicated in a number of functions including endocytosis, potocytosis and signal transduction. Caveolin (VIP-21) is thought to play a structural role in the formation of non-clathrin-coated vesicles in a number of different cell types. Caveolin-3, or M-caveolin, was identified as a muscle- specific form of the caveolin family. We show that caveolin-3 co- purifies with dystrophin, and that a fraction of caveolin-3 is a dystrophin-associated protein. We isolated the gene for human caveolin- 3 and mapped it to chromosome 3p25. We determined the genomic organization of human caveolin-3 and devised a screening strategy to look for mutations in caveolin-3 in patients with muscular dystrophy. Of 82 patients screened, two nucleotide changes were found that resulted in amino acid substitutions (G55S and C71W); these changes were not seen in a control population. The amino acid changes map to a functionally important domain in caveolin-3, suggesting that these are not benign polymorphisms and instead are disease-causing mutations.      

Evaluation of nonisotopic labeling and detection techniques for nucleic acid hybridization

We have used a double-stranded DNA probe linked to the cystic fibrosis locus to detect a single-copy gene from varying amounts of genomic DNA, with Southern blot analysis. The DNA plasmid probe was labeled with either biotin or digoxigenin. Biotin or digoxigenin was then linked to alkaline phosphatase (ALP) with use of streptavidin or anti-digoxigenin antibodies, respectively. ALP activity was then detected with a chromogenic (BCIP/NBT), chemiluminogenic (AMPPD), or fluorogenic (HNPP) substrate. Our results suggest that biotin and digoxigenin perform similarly and that the three substrates exhibit similar detectability under appropriate substrate incubation times: 20-120 min (AMPPD), 2-12 h (HNPP), and 18-48 h (BCIP/NBT). Under optimised conditions and the probe used, these methods detect single-copy genes from as little as 0.3 μg of total genomic DNA. © 1993 Wiley-Liss, Inc.     

Is there a relationship between antipsychotic blood levels and their clinical efficacy? An analysis of studies design and methodology

Summary— There are now more than 50 studies concerning neuroleptic blood levels and clinical outcome relationships. Haloperidol, the most studied, is the only antipsychotic permitting some conclusions. A number of authors suggest that the striking lack of agreement between different studies results from heterogeneity of their quality. Here, we have used a scoring system for assessing the quality of those studies. According to this system, none (0/14) of the studies having a score <0.60 was able to show a therapeutic window, as compared to 53% (10/19) of those having a score ≥0.60 (p = 0.002, Fisher exact test). Also, the studies able to identify the presence of a therapeutic window during haloperidol treatment were those having sample sizes >20 ( p = 0.06) and those whose patients were treated with fixed doses ( p = 0.02). The diagnosis of schizophrenia in the studies seems not to be an exclusive condition, as compared with those also including schizophreniform and schizoaffective disorders (p = 0.12). Our qualitative analysis of haloperidol blood level publications seem to indicate that an upper limit may exist for haloperidol efficacy; values above this limit seem not to provide any supplementary clinical improvement and may even reduce therapeutic effect.     

Thresholds for detection of a target against a background grating suggest visual dysfunction in migraine with aura but not migraine without aura

Square-wave gratings with particular spatial characteristics in visual illusions. Patients with migraine are particularly susceptible to these illusions and report disc. it. Their discomfort tends to be greater when the gratings are illuminated by red light, a tendency 1 known by controls. Gratings that induce illusions have been found to impair the recognition of opt superimposed targets in headache-free control subjects. We measured the impairment of target detection under illuminants of various chromaticities in migraineurs with and without aura and in mat controls. Migraineurs with aura had significantly higher thresholds for target detection than either migraineurs without aura or controls; in addition, the effect of chromaticity was slightly more pronounced in both migraine groups than in the control group. These findings are consistent with a recent suggestion that migraine with aura might give rise to subclinical damage to the primary visual cortex.     

Kallikreins as markers of disseminated tumour cells in ovarian cancer-- a pilot study.

BACKGROUND: Kallikreins are a family of secreted serine proteases, encoded by 15 genes which all localize in tandem on chromosome 19q13.4. Several members of this family have been previously associated with ovarian cancer. Kallikreins 6 (KLK6) and 10 (KLK10) are elevated in tumour cells, serum and ascites fluid of ovarian cancer patients and correlate with disease prognosis. Other kallikreins that have been related to ovarian cancer include KLK4, 5, 7, 8, 9, 11, 13, 14 and 15. We hypothesized that KLK6 and KLK10 can be utilized to monitor dissemination of ovarian cancer cells in blood and ascites fluid of ovarian cancer patients. METHODS: RNA was isolated by immunomagnetic separation of cancer cells and was amplified by RT-PCR. RESULTS: Screening for disseminated cancer cells in blood from 24 ovarian cancer patients, with RT-PCR for KLK6 mRNA, resulted in 75% positivity; however, this was not different from the positivity of normal controls. By utilizing KLK10 as a marker, the positivity of patients was 40% versus 20% of controls. Screening of ascites fluid of ovarian cancer patients revealed 90% positivity for KLK6 and KLK10 mRNA compared with 33% for other cancer types. Significant correlations were identified among mRNA of KLK4, 5, 6, 7, 8, 9, 10, 11, 13, 14 and 15 in cancer cells isolated from ascites fluid. CONCLUSION: Kallikrein expression by ovarian cancer cells is not specific enough for detecting disseminated disease. Kallikrein expression may have some value for differentiating ovarian cancer from other types of cancer or from non-malignant diseases that lead to ascites accumulation.