Weight loss in a murine cachexia model is not associated with the cytokines tumour necrosis factor-alpha or interleukin-6.

Daily administration of an escalating dose of tumour necrosis factor-alpha (TNF-alpha) to female NMRI mice caused a progressive loss of body weight representing 12% of the original weight over a 6-day period. Weight loss was associated with a decreased food intake and pair-fed controls exhibited a weight loss of similar magnitude to that caused by TNF-alpha. However, weight loss in animals bearing a murine adenocarcinoma (MAC16) occurred without a change in energy intake and thus differed from that produced by TNF-alpha. Anti-TNF-alpha monoclonal antibodies at levels capable of protecting mice against lethal endotoxaemia were ineffective in reversing weight loss in animals bearing the MAC16 tumour and had no effect on the increase in tumour volume. Circulating levels of interleukin-6 were not elevated in animals bearing the MAC16 tumour and with a weight loss between 1.8 and 5.4 g. These results suggest that these cytokines are not involved in the cachexia produced by this murine tumour.     

Varix of the fetal intra-abdominal umbilical vein: comparison with normal.

To compare the normal extrahepatic portion of the fetal intra-abdominal umbilical vein (FIUV) with varix of the FIUX, we prospectively measured the diameter of the FIUV in 150 uncomplicated second and third trimester pregnancies and compared these results with retrospective review of nine fetuses with varix of the FIUV as an isolated prenatal sonographic finding. The diameter of the normal FIUV increases linearly from approximately 3 mm at 15 menstrual weeks to approximately 8 mm at term (R = 0.92). The nine fetuses with FIUV varix had a FIUV diameter 6 to 12 standard deviations above the mean for age. Four (44%) of the nine fetuses with FIUV varix subsequently died, including one with trisomy 21. One of the remaining fetuses developed severe hydrops 2 weeks after the initial detection of the FIUV varix. FIUV varix appears to carry an increased risk of adverse fetal outcome, including fetal demise.     

Registration of myocardial infarction and stroke in the Kilkenny Health Project: Methodology

A myocardial infarction and stroke register was established in January 1987 as part of the evaluation of the Kilkenny Health Project This is a community programme which aims to reduce risk factors for coronary heart disease. The register records acute myocardial infarction and stroke in residents of County Kilkenny and of the reference county. This will provide accurate estimates of the incidence of these diseases and of trends over time. Methods used comply with the protocol in use by the WHO MONICA Project. This will allow comparison of the incidence of coronary heart disease and stroke in this register with that in other MONICA locations, including that in Belfast, Northern Ireland.     

Analytical sensitivity, reproducibility of results, and clinical performance of five PCR assays for detecting Chlamydia pneumoniae DNA in peripheral blood mononuclear cells

Chlamydia pneumoniae has been associated with atherosclerosis and coronary artery disease (CAD), and its DNA has been detected in atheromatous lesions of the aorta, carotid, and coronary arteries by a variety of PCR assays. The objective of this study was to compare the performances of five published PCR assays in the detection of C. pneumoniae in peripheral blood mononuclear cells (PBMCs) from patients with coronary artery disease. The assays included two conventional PCRs, one targeting a cloned PstI fragment and one targeting the 16S rRNA gene; two nested PCRs, one targeting the 16S rRNA gene and one targeting ompA; and a touchdown enzyme time release (TETR) PCR, targeting the 16S rRNA gene. All PCRs had similar analytical sensitivities and detected a minimum of 0.005 inclusion-forming units (IFU) of C. pneumoniae; the ompA nested PCR and the TETR PCR were slightly more sensitive and detected 0.001 IFU. Assay reproducibility was examined by testing 10 replicates of C. pneumoniae DNA by each assay. All five assays showed excellent reproducibility at high levels of DNA, with scores of 10 out of 10 for 0.01 IFU, but exhibited decreased reproducibility for smaller numbers of C. pneumoniae IFU for all tests. Pairwise comparison of test results indicated that there was a significant difference between tests (Cochran Q = 32.0, P<0.001), with the PstI fragment (P<0.001) and 16S rRNA (P = 0.002) assays having lower reproducibility than the nested ompA and TETR assays. To further analyze assay sensitivity, C. pneumoniae-infected U-937 mononuclear cells were added to whole blood, and extracted mononuclear-cell DNA was tested by each assay. All five assays showed similar sensitivities, detecting 15 infected cells; three assays detected 3 infected cells, while all assays were negative at the next dilution (1.5 infected cells). A striking difference in performance of the five assays was seen, however, when PBMCs from CAD patients were tested for C. pneumoniae DNA. The ompA nested PCR detected C. pneumoniae DNA in 11 of 148 (7.4%) specimens, the 16S rRNA nested PCR detected 2 positives among the 148 specimens (1.4%) (P<0.001), and the other 3 assays detected no positive specimens (P<0.001, compared with the ompA assay). These results indicate that analytical sensitivity alone does not predict the ability of an assay to detect C. pneumoniae in whole-blood-derived PBMCs. Before standardized assays can be used in wide-scale epidemiological studies, further characterization of these assays will be required to improve our understanding of their performance in the detection of C. pneumoniae in clinical material.