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In a multi-health center study, a new rapid optical immunoassay (OIA) for the detection of Shiga toxin types 1 and 2, the BioStar OIA SHIGATOX kit (Inverness Medical Professional Diagnostics, Inc.), was used to prospectively screen 742 fresh fecal samples for Shiga toxins in parallel with the Premier enterohemorrhagic Escherichia coli (EHEC) kit (Meridian BioScience, Inc.) with and without enrichment of the specimens by incubation in MacConkey broth. Additionally, 85 previously tested frozen fecal samples were assessed as described above. All positive immunoassay results were confirmed by the Vero cell cytotoxicity assay. A further modification of the screening procedure was evaluated on 470 of the prospectively screened specimens. Swabs of growth from conventionally plated stool culture media were subjected to the OIA SHIGATOX, and results were compared with those obtained with the Premier EHEC kit following broth enrichment. Overall, the OIA SHIGATOX kit was significantly more sensitive than the Premier EHEC kit on fresh direct stool specimens (sensitivities, 96.8% and 83.9%, respectively; P < 0.05). The two assays performed equally well with each other on frozen and broth-enriched samples. The colony sweep method used in conjunction with the OIA kit was somewhat more effective at detection of Shiga toxins from growth on agar than the overnight broth enrichment procedure used with the Premier EHEC assay (sensitivities, 100% and 92%, respectively; P < 0.09). Overall, the OIA SHIGATOX kit provided rapid, easy-to-interpret results and was highly effective at detection of Shiga toxin-producing E. coli in fecal samples and overnight cultures. more...

Antiphospholipid antibodies (aPL) have been implicated in the pathogenesis of coronary artery disease (CAD). We evaluated the presence of aPL in patients with chest pain/acute coronary syndromes (ACS) to determine if aPL were associated with the presence and severity of CAD, adverse outcomes, and other coronary risk factors. Patients with chest pain/ACS were evaluated for aPL prior to diagnostic and therapeutic investigations. Coronary angiograms were graded according to the severity of disease. Risk factors, including family histories, were assessed and patients were followed for adverse outcomes. To date, 232 patients (116 M, 116 F, mean age 63 years) with a mean follow-up of 9 months were studied. Thirty-seven percent (86/232) were positive for one or more aPL. More women, 49/86 (57%), were aPL positive versus men, 37/86 (43%). The presence of aPL appeared associated with both presence and severity of CAD (P = 0.176 women; P = 0.163 men). In patients undergoing procedures (angioplasty, stent, bypass), aPL was significantly associated with both an increase in adverse cardiac outcomes (P = 0.045) and extracardiac thrombotic events (P = 0.033). Anti-beta2 glycoprotein-1 (abeta2GP1) was the most frequent aPL, occurring in 68.5% of aPL-positive patients with CAD. Anticardiolipin antibody (aCL) occurred in only 7.4%. IgM isotypes were the most frequent for all categories of aPL (range 55-90%). Family history of antiphospholipid syndrome (APS)-related events was more significant in aPL-positive than aPL-negative individuals (P = 0.027). more...

We describe an improved procedure using a standard microplate immunoassay reader to measure the concentration of troponin T in human serum. We also describe an immunoassay for troponin I in serum. Only 160 microliters of serum are needed for a single analysis of each troponin. For comparison, creatine kinase MB mass analysis in serum was performed with a commercial luminometric method. From 95 apparently healthy people the following values were obtained: creatine kinase MB mass 2.6 +/- 1.2 micrograms/l, troponin T 0.027 +/- 0.025 microgram/l and troponin I 0.03 +/- 0.031 microgram/l. We compared the results of troponin T and troponin I methods with each other, as well as with those of creatine kinase MB mass measured in 48 patients with verified acute myocardial infarction and in 60 control patients with non-cardiac chest pain. The correlation between troponin T and troponin I values was 0.91 for the total material and 0.94 for 48 patients with acute myocardial infarction. Troponin I showed better earlier sensitivity than troponin T (p = 0.043). In nine patients in the control group, creatine kinase MB mass exceeded the reference limit of 5.0 micrograms/l, while in two patients the cut-off limit of 10.0 micrograms/l was also surpassed, pointing to non-specificity. In the group of infarct patients, the highest serum creatinine value was 193 mumol/l, whereas in the control group it was 406 mumol/l. The sera of patients with impaired renal function without any cardiac failure showed no increase in troponin T and troponin I values. In conclusion, serum creatine kinase MB mass and troponin I seem to confirm an acute myocardial infarction more rapidly than does troponin T; troponin I has the highest cardiac specificity. more...

The purpose of this study was to identify which of the biochemical, immunological, or functional parameters derived before surgery as part of a systemic evaluation were helpful in predicting the frequency of rejection episodes, the chance of survival, and the cause risk of death (should death occur) of patients after orthotopic liver transplantation (OLTx). Ninety-eight adult patients who had an extensive preoperative protocol evaluation were studied before OLTx. The biochemical parameters assessed were albumin, prothrombin time, bilirubin, and ICG clearance. The immunologic parameters assessed included total lymphocytes, T3 cells, T4 cells, T8 cells, and the T4/T8 ratio. The degree of histocompatibility antigen (HLA) matching between the donor and the recipient was also evaluated in 80 of the 98 patients studied. Most postoperative deaths occurred within 12 weeks of the procedure (24%; 24 of 98 patients); 13 patients (13%) died within the first 6 postoperative weeks, of either bacterial or fungal sepsis. An additional 14 patients (14%) died after the initial 6 postoperative weeks due, primarily of an acquired viral and/or protozoan infection (p less than 0.01). During the first 6 weeks, survival was better for patients with cholestatic liver disease (ChLD, 93%, n = 45) and miscellaneous liver diseases (MISC, 100%, n = 10) than it was for those with parenchymal liver diseases (PLD, 77%, n = 43). Although albumin, prothrombin time, T4/T8 ratios, and per cent T8 cells were statistically different in patients with PLD as compared with those with ChLD, these parameters, as well as the per cent T4 cells, serum bilirubin level, per cent retention of ICG at 15 minutes, and the plasma ICG disappearance rate were not found to be of substantial help in predicting patient survival or non-survival. Moreover, neither the degree of HLA matching nor the number of rejection episodes differed between surviving and nonsurviving patients. The results of this study suggest that patients with PLD are at increased risk of early postoperative death after OLTx because of bacterial and/or fungal sepsis, as compared with patients operated upon for ChLD. Better pre-, intra-, and postoperative predictors of risk of death and complications are needed to reduce the early mortality observed after orthotopic liver transplantation. more...

Orthotopic liver transplantation was performed in two groups of dogs; Group I animals consisted of large dogs that served as recipients of livers obtained from smaller dogs while Group II animals consisted of dogs that received liver from donor dogs of nearly the same size. The small-for-size livers transplanted into the Group I dogs rapidly increased in size over the course of 2 weeks until they achieved a size equal to that originally present in the larger recipient dogs. In contrast, the livers transplanted into dogs of the same size as the donors underwent some degree of atrophy. In both groups of animals, plasma levels of insulin and glucagon and hepatic (graft) activities of thymidine kinase and ornithine decarboxylase were followed serially. The only difference between the two groups of animals for these measures was that the ornithine decarboxylase activity rose to a greater degree in the liver that underwent graft enlargement. These data suggest that recipient size determines, at least in part, liver graft size once it is transplanted. These data also suggest that of the parameters followed, only ornithine decarboxylase activity parallels the finding of growth of the transplanted liver. more...