The predictive value of history in dyspepsia

Symptomatic patients referred to an open-access upper gastrointestinal endoscopy completed a detailed, self-administered questionnaire aimed at assessing the predictive value of history in dyspepsia. Nine hundred and thirty patients were suitable for analysis. Of these, 29% were found to have organic dyspepsia. A substantial overlap of symptoms and demographic data was found among the various endoscopic diagnoses. Discriminating variables were identified by stepwise logistic regression analysis and included in predictive score models. Pain relieved by antacids, age above 40 years, previous peptic ulcer disease, male sex, symptoms provoked by berries, and night pain relieved by antacids and food were found to predict organic dyspepsia with a sensitivity and specificity of approximately 70%, when applied on the observed material. Similar probabilities were found for score models of peptic ulcer and esophagitis. In general, the low prevalence of organic diseases resulted in low positive and high negative predictive values. Accordingly, the main impact of the predictive models may be to reduce the number of negative endoscopies rather than to predict a precise diagnosis. Independent of disease category and age, 41% of the subjects expressed a fear of malignancy, emphasizing the value of reassurance from a negative endoscopy.     

Axon clinical chemistry analyzer evaluated according to ECCLS protocol.

We assessed the analytical performance of the Axon system (Bayer Diagnostici), according to the European Committee for Clinical Laboratory Standards guidelines, for assay of 12 analytes: cholesterol, creatinine, glucose, total protein, urea, uric acid, alkaline phosphatase, alpha-amylase, aspartate aminotransferase, creatine kinase, sodium, and potassium. The field evaluation lasted approximately 5 months and involved the collection of approximately 10,000 data points with the Axon. The following results were obtained: The highest CVs for controls and human sera at different concentration/activity values were 2.2% for within-run imprecision (n = 60; 3 days, pooled estimate) and 3.5% for the between-day imprecision (n = 20 days). Close correlation was found with results for patients' specimens assayed with comparative instruments (Hitachi 717 for substrates and enzymes, Beckman Synchron EL/E4A for electrolytes). No drift was observed during 8 h of operation. The linearity range was broad, sometimes exceeding the manufacturer's claims. No sample-, reagent-, or cuvette-related carryover was found. Measurement of control sera gave results within +/- 5% of the assigned values. We conclude that good reliability and practicability make the Axon system suitable for laboratories with various needs.     

Ki-67 labeling index in breast cancer

Measurements of cell cycle kinetics have been found to correlate with the clinical course of patients with breast cancer. However, the thymidine labeling index and more rapid methods like flow cytometry remain complicated and costly. We assessed cell proliferation of 67 breast carcinomas by an immunoperoxidase procedure using a monoclonal antibody, Ki-67, which reacts with a nuclear antigen in proliferating cells. The percentage of Ki-67 positive cells ranged from 2% to 70%. Tumors with high mitotic rate, high nuclear grade, high histologic grade, and negative estrogen receptors had statistically higher Ki-67 labeling rates. We found no significant differences between the Ki-67 labeling rate and other clinical (age at diagnosis, menopausal status) or pathologic (necrosis, fibrosis, vascular invasion, lymphatic invasion, cellular reaction, tumor size, lymph node metastases) features assessed. These results parallel previously reported data, and confirm that this immunohistochemical staining of breast carcinoma by Ki-67 monoclonal antibody can be considered a rapid and convenient method for assessing cell cycle kinetics. However, further studies, evaluating the correlation between Ki-67 labeling rate and prognosis are needed to better define the real usefulness of this analysis in clinical practice.     

Cold Lymphocytotoxic Antibodies in Systemic Lupus erythematosus

Optimum conditions were established for the assay of cold lymphocytotoxic antibodies (cLCTA) in serum from patients with systemic lupus erythematosus (SLE). The optimum temperature of the incubation step with complement was 15 degrees C. For target cells incubated with dextran a significantly higher percentage of damaged cells (p less than 0.005), a faster rate of cell damage (p less than 0.001) and a requirement for less complement was observed than for target cells not incubated with dextran. Under optimum conditions in the cytotoxicity assay, 62% of SLE sera damaged more than 60% of the target cells, whereas 73% of the sera from control donors damaged less than 20% of the target cells. In multiple serum samples obtained during follow-up of 30 patients with SLE, the serum cytotoxic activity or titer of cLCTA fluctuated and did not relate to clinical symptoms of disease activity. In sera obtained during active disease the cytotoxic activity was related to the anti-dsDNA antibody level and with levels of circulating immune complexes measured by the Raji cell assay and the indirect granulocyte phagocytosis test. We found no restricted reactivity of cLCTA against phenotypically distinct T-lymphocyte subpopulations with different immunoregulatory functions. The reactivity pattern of cLCTA towards the various T-lymphocyte subpopulations was not related to disease activity. We conclude that cLCTA in patients with SLE represent an epiphenomenon, being the result of a hyperreactive B-cell system rather than the cause of the disease.     

Decreased airway mucosal prostaglandin E2 production during airway obstruction in an animal model of asthma.

Heaves is a respiratory disorder of horses and ponies characterized by bouts of acute airway obstruction and airway hyperresponsiveness. We measured prostaglandin E2 (PGE2) and 15-hydroxyeicosatetraenoic acid (15-HETE) production in vitro in tracheal epithelium obtained from six affected horses at the time of acute airway obstruction as compared with six matched control horses. Strips of epithelium and subepithelial tissue were prepared and stimulated with A23187, histamine, and bradykinin. The PGE2 and 15-HETE in media from strips was quantitated by radioimmunoassay. 15-HETE above the limits of accurate detection was found in epithelial strips of only two principal animals and in none of the control horses, and the amount of 15-HETE was not increased when strips were stimulated. Epithelial strips from affected horses tended to produce less PGE2 than did strips from control horses, and there was a significant correlation between epithelial PGE2 production and the time taken for affected animals to develop airway obstruction. Subepithelial tissue strips from control horses produced significantly more PGE2 in response to A23187 and bradykinin than did strips from affected horses. We conclude that equine tracheal epithelium is not a significant source of 15-HETE. Airway mucosal PGE2 production is reduced in horses with heaves, which suggests that a relative decrease in this bronchorelaxant substance may be a factor in the pathogenesis of this model of asthma.