Use of a sensitive enzyme immunoassay for human thyrotropin in the diagnosis of hyperthyroidism

A sensitive, simultaneous sandwich enzyme immunoassay for TSH was evaluated especially for its ability to distinguish hyperthyroid patients from the euthyroid population. A total of 140 patient samples was analzyed by this assay as well as with a two-step sandwich radioimmunoassay. The diagnostic sensitivity of the thyrotropin assay was 92.5% and the specificity was 88%. False negatives by thyrotropin assay included two patients with Graves' disease who were being treated with propranolol at the time of testing and one patient who was considered hyperthyroid while receiving synthroid. Twelve patients with elevated free thyroxine index levels were considered euthyroid and 50% of these had thyrotropin values that were undetectable; most were elderly patients with nonthyroidal illnesses. Although the thyrotropin enzyme immunoassay had good sensitivity and precision for the detection of hyperthyroidism, our data suggest the limitation of a single thyrotropin determination in establishing the euthyroid state, especially in elderly patients with associated nonthyroidal illnesses and hyperthyroxinemia.     

Changes in depression during and following pregnancy

Summary. .Rates of depression were studied in a sample of over 9000 women who were participants in the Avon Longitudinal Study of Pregnancy and Childhood. Assessments of depression were made at 18 and 32 weeks gestation, and at 8 and 32 weeks postpartum. Changes in depressive status across time were modelled using latent Markov modelling methods. This analysis showed that when classification errors were taken into account there was relatively high stability in diagnostic status during pregnancy and after pregnancy. However, the transition from late pregnancy to the early postnatal period showed evidence of increased instability and remission of depression. The net effects of this were that rates of depression tended to decline following childbirth. The implications of these results for a series of issues including measurement errors in depression reports and the prevalence of depression before and after childbirth are discussed.     

Maternal satisfaction following post-shelter family reunification

The purpose of this study was to examine the correlates of post-shelter maternal family satisfaction in a group of youth who were reunified with their families following a shelter stay. Findings indicated that higher ratings of family satisfaction were related to greater maternal problem solving skill and less family conflict.     

TNFα Inhibits Schwann Cell Proliferation, Connexin46 Expression, and Gap Junctional Communication

Schwann cell responses to nerve injury are stimulated, in part, by inflammatory cytokines. This study compares changes in the phenotype of cultured Schwann cells after exposure to the cytokine tumor necrosis factor (TNF)-α or the mitogen neu differentiation factor (NDF)-β. TNFα inhibited proliferation in a dose-dependent manner without altering Schwann cell survival. TNFα also reduced both gap junctional conductance and Lucifer yellow dye coupling between Schwann cells. Moreover, both P₀and glial fibrillary acidic protein (GFAP) immunoreactivity were reduced. By contrast, NDFβ initially had little effect on cell division although it reduced junctional coupling within 8 h. However, by 48 h, NDFβ stimulated proliferation with a concomitant increase in coupling. Dividing Schwann cells (BrdU⁺) were preferentially dye coupled compared to nondividing cells, indicating an association between proliferation and coupling. Moreover, cultured Schwann cells expressed connexin46 mRNA and protein, and changes in the levels of the protein correlated with the degree of proliferation and coupling. The data thus provide evidence for cytokine-induced modulation of Schwann cell antigenic phenotype, proliferation, and gap junction properties. These observations suggest that enhanced gap junctional communication among Schwann cells after nerve injury could help to coordinate cellular responses to the injury, and that TNFα may be a signal which terminates proliferation as well as junctional communication.     

Assessment of the potential in vivo genotoxicity of fluoranthene

Fluoranthene is a ubiquitous environmental pollutant. Althoughfluoranthene is mutagenic in bacterial and mammalian in vitrocell systems following metabolic activation by rat liver fraction,information on in vivo mutagenicity is lacking and studies ontumour initiating activity in mice are equivocal. In the presentstudy, the potential genetic hazard to man was assessed usingthe mouse bone marrow micronucleus and rat liver unscheduledDNA synthesis test systems. Fluoranthene did not show any evidenceof genotoxicity in either of the in vivo assays following acuteoral administration at levels of up to 2000 mg/kg b.w. ¹To whom correspondence should be addressed     

Y chromosome loss in esophageal carcinoma: An in situ hybridization study

Carcinoma of the esophagus shows a strong male predominance and other epidemiologic differences from cancers arising at other sites. In this study, the prevalence of Y chromosome loss in 29 carcinomas of the esophagus and 53 carcinomas arising elsewhere in the aerodigestive tract was assessed by in situ hybridization of formalin-fixed paraffin-embedded tissue sections. Absence of the Y chromosome was defined as (1) negative staining for Y in neoplastic cells with positive staining for Y in immediately adjacent nonneoplastic epithelial and stromal cells, (2) positive staining of neoplastic cells with control probes for chromosomes X and 17, and (3) similar results at different stringencies and levels of protein digestion. According to these criteria, absence of the Y chromosome was observed in 13 of 14 (93%) adenocarcinomas of the esophagus, 8 of 13 (62%) squamous cell carcinomas of the esophagus, and 5 of 53 (9%) carcinomas arising in other sites. For the neoplasms examined, Y chromosome deletion was strongly and selectively associated with carcinomas, particularly adenocarcinomas, of the esophagus (P < .0001). These findings suggest that Y chromosome loss may be pathogenetically significant in these neoplasms. © 1993 Wiley-Liss, Inc.     

Comparison of aminoglycoside concentrations measured in plasma versus serum

The terms "serum concentration" and "plasma concentration" are often used interchangeably in therapeutic drug monitoring, but few studies have addressed the comparability of serum and plasma drug concentrations. Before implementing a change in the procedure for measuring aminoglycoside concentrations in our institution, we prospectively compared values for tobramycin and gentamicin concentrations measured in serum and plasma. For the 208 samples that were tested, plasma aminoglycoside concentrations were significantly lower than those in serum. This relationship was similar for tobramycin and gentamicin, and was unaffected by the presence of concurrent therapy with ticarcillin. This difference, while statistically significant, was not, in our estimation, of sufficient magnitude to be of clinical importance. Plasma aminoglycoside concentrations may be considered equivalent to serum concentrations and, owing to the shorter processing time involved, appear to be the preferred medium for measuring these values.