A multiplex PCR test for determination of mating type applied to the plant pathogens Tapesia yallundae and Tapesia acuformis

A multiplex PCR test for determining mating type of the pathogens Tapesia yallundae and Tapesia acuformis is described. The test involves three primers: a "common" primer annealing to DNA sequence conserved in the flanking region of both mating-type idiomorphs and two specific primers annealing to sequence in either the MAT-1 or the MAT-2 idiomorphs. Locating the specific primers in different positions relative to the common primer yielded PCR products of 812 or 418 bp from MAT-1 and MAT-2 isolates, respectively. The test was used successfully to determine the mating type of 118 isolates of T. yallundae and T. acuformis from Europe, North America, and New Zealand. Isolates of both mating types were found on all continents for both species despite the rarely observed occurrence of sexual reproduction of T. acuformis. The multiplex test design should be applicable to other ascomycete species, of use in studies of MAT distribution and facilitating sexual crossing by identifying compatible isolates.     

Evidence for a nutritional disorder of Oxalis acetosella L. on acid forest soils; II. Diagnostic field experiments and nutrient solution studies

Different field experiments were performed to discover the main factor(s) responsible for the poor leaf growth, moderate propagation and leaf chlorosis of Oxalis acetosella in an old Norway spruce stand with acid soil (Höglwald Forest). A previous study had suggested, that Ca (or Mg) deficiency or Mn toxicity could be involved.In a Main Diagnostic Field Experiment with an intact population, Ca and Mg were either applied as sulphate or carbonate to distinguish between nutritional and pH effects. Mn and Si were also applied to aggravate or overcome possible effects of Mn toxicity. Enhancement experiments with different amounts of CaSO₄ were conducted to investigate the Ca dose-effect relationship under field conditions. Additional trials with SrCO₃, BaCO₃ and NaHCO₃ had the goal to raise the soil pH without supply of nutrients.Greenhouse experiments with Oxalis acetosella supplemented the field studies by investigating the Ca and Mn dose-effect relationships under controlled conditions. Growth, vitality and nutrition of Oxalis were studied in a nutrient solution culture at pH 4.0 over a range of concentrations of Ca (20 to 5000 mol L_-1) and Mn (5 to 1000 mol L_-1) respectively. Furthermore, the effects of two contrasting ammonium/nitrate ratios were tested. The nutritional composition of the basal nutrient solution and the microclimate in the greenhouse were as far as possible adjusted to the environmental conditions of the plant in the Höglwald Forest.All these studies led to the conclusion, that the moderate growth and vitality of Oxalis in the Höglwald Forest was mainly due to an insufficient Ca supply, rather than an effect of Mg deficiency, low soil pH or Mn toxicity. The application of CaSO₄ caused a similar stimulation of the growth as CaCO₃. A clearly positive, close CaSO₄ dose-effect relationship was detected in field experiments as well as in the nutrient solution study. The same type of leaf chloroses as in the field was reproduced through low Ca nutrient solutions. Predominant ammonium nutrition may significantly impair Ca uptake.Oxalis acetosella displayed a relatively high leaf tissue tolerance of excessive Mn. There was no indication for a Mn-induced Ca deficiency in the Höglwald Forest. Enhanced Si uptake led to a partial vitalization of Oxalis; the reason for that remained unclear.     

Diagnostic pitfalls in the evaluation of fine needle aspiration cytology of the thyroid: correlation with histopathology in 260 cases

Objectives:  Fine needle aspiration cytology (FNAC) of the thyroid is a non-invasive, cost-effective screening procedure that is valuable for distinguishing neoplastic lesions from non-neoplastic nodules. The aim of this study was to determine the diagnostic accuracy of FNACs performed at our institution by correlating FNAC results with histopathological diagnoses.
Methods:  Two hundred and seventy-one aspiration cytology specimens followed by thyroidectomy were included in the study, and the results of 260 adequate FNACs were compared with their histological diagnoses.
Results:  The sensitivity and specificity of thyroid FNAC for detecting neoplasia were 92.6% and 91.6%, respectively. There were 15 (5.7%) false positives and six (2.3%) false negatives.
Conclusions:  The results showed that follicular cells that exhibit some of the features of papillary carcinoma could be observed in a cytology slide of Hashimoto's thyroiditis, leading to a diagnostic pitfall. In addition, cellularity and overlapping cytological criteria in hyperplasia might lead to a false diagnosis.     

Combined Psychophysiological Assessment of ADHD: A Pilot Study of Bayesian Probability Approach Illustrated by Appraisal of ADHD in Female College Students

Manifestations of ADHD are observed at both psychological and physiological levels and assessed via various psychometric, EEG, and imaging tests. However, no test is 100% accurate in its assessment of ADHD. This study introduces a stochastic assessment combining psychometric tests with previously reported (Consistency Index) and newly developed (Alpha Blockade Index) EEG-based physiological markers of ADHD. The assessment utilizes classical Bayesian inference to refine after each step the probability of ADHD of each individual. In a pilot study involving six college females with ADHD and six matched controls, the assessment achieved correct classification for all ADHD and non-ADHD participants. In comparison, the classification of ADHD versus non-ADHD participants was < 85% for any one of the tests separately. The procedure significantly improved the score separation between ADHD versus non-ADHD groups. The final average probabilities for ADHD were 76% for the ADHD group and 8% for the control group. These probabilities correlated (r = .87) with the Brown ADD scale and (r = .84) with the ADHD-Symptom Inventory used for the screening of the participants. We conclude that, although each separate test was not completely accurate, a combination of several tests classified correctly all ADHD and all non-ADHD participants. The application of the proposed assessment is not limited to the specific tests used in this study--the assessment represents a general paradigm capable of accommodating a variety of ADHD tests into a single diagnostic assessment.