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Context: Ultrasound (US) risk-stratification systems for investigation of thyroid nodules may not be as useful as anticipated., Objective: We aimed to assess the performance and costs of the American College of Radiology Thyroid Image Reporting And Data System (ACR-TIRADS)., Design Settings and Participants: We examined the data set upon which ACR-TIRADS was developed, and applied TR1 or TR2 as a rule-out test, TR5 as a rule-in test, or applied ACR-TIRADS across all nodule categories. We assessed a hypothetical clinical comparator where 1 in 10 nodules are randomly selected for fine needle aspiration (FNA), assuming a pretest probability of clinically important thyroid cancer of 5%., Results: The gender bias (92% female) and cancer prevalence (10%) of the data set suggests it may not accurately reflect the intended test population. Applying ACR-TIRADS across all nodule categories did not perform well, with sensitivity and specificity between 60% and 80% and overall accuracy worse than random selection (65% vs 85%). Test performance in the TR3 and TR4 categories had an accuracy of less than 60%. Using TR5 as a rule-in test was similar to random selection (specificity 89% vs 90%). Using TR1 and TR2 as a rule-out test had excellent sensitivity (97%), but for every additional person that ACR-TIRADS correctly reassures, this requires >100 ultrasound scans, resulting in 6 unnecessary operations and significant financial cost., Conclusions: Perhaps surprisingly, the performance ACR-TIRADS may often be no better than random selection. The management guidelines may be difficult to justify from a cost/benefit perspective. A prospective validation study that determines the true performance of TIRADS in the real-world is needed., (© Endocrine Society 2020.)

Antenatal glucocorticoid therapy significantly improves the short-term systemic outcomes of prematurely born infants, but there is limited information available on their impact on neurodevelopmental outcomes in at-risk preterm babies exposed to perinatal asphyxia. Preterm fetal sheep (0.7 of gestation) were exposed to a maternal injection of 12 mg dexamethasone or saline followed 4 h later by asphyxia induced by 25 min of complete umbilical cord occlusion. In a subsequent study, fetuses received titrated glucose infusions followed 4 h later by asphyxia to examine the hypothesis that hyperglycemia mediated the effects of dexamethasone. Post-mortems were performed 7 days after asphyxia for cerebral histology. Maternal dexamethasone before asphyxia was associated with severe, cystic brain injury compared to diffuse injury after saline injection, with increased numbers of seizures, worse recovery of brain activity, and increased arterial glucose levels before, during, and after asphyxia. Glucose infusions before asphyxia replicated these adverse outcomes, with a strong correlation between greater increases in glucose before asphyxia and greater neural injury. These findings strongly suggest that dexamethasone exposure and hyperglycemia can transform diffuse injury into cystic brain injury after asphyxia in preterm fetal sheep.

The dual-representation model of posttraumatic stress disorder (PTSD; Brewin, Gregory, Lipton, & Burgess, Psychological Review, 117, 210-232 2010) argues that intrusions occur when people fail to construct context-based representations during adverse experiences. The present study tested a specific prediction flowing from this model. In particular, we investigated whether the efficiency of temporal-lobe-based spatial configuration learning would account for individual differences in intrusive experiences and physiological reactivity in the laboratory. Participants (N = 82) completed the contextual cuing paradigm, which assesses spatial configuration learning that is believed to depend on associative encoding in the parahippocampus. They were then shown a trauma film. Afterward, startle responses were quantified during presentation of trauma reminder pictures versus unrelated neutral and emotional pictures. PTSD symptoms were recorded in the week following participation. Better configuration learning performance was associated with fewer perceptual intrusions, r = -.33, p < .01, but was unrelated to physiological responses to trauma reminder images (ps > .46) and had no direct effect on intrusion-related distress and overall PTSD symptoms, rs > -.12, ps > .29. However, configuration learning performance tended to be associated with reduced physiological responses to unrelated negative images, r = -.20, p = .07. Thus, while spatial configuration learning appears to be unrelated to affective responding to trauma reminders, our overall findings support the idea that the context-based memory system helps to reduce intrusions.

A potato breeding strategy is presented which avoids the common but ineffective practice of intense early-generation visual selection between seedlings in a glasshouse and spaced plants at a seed site. Once pair crosses have been made, progeny tests are used to discard whole progenies before starting conventional within-progeny selection at the unreplicated small-plot stage. Clones are also visually selected from the best progenies for use as parents in the next cycle of crosses whilst they are multiplied to provide enough tubers for assessment of their yield and quality. Mid-parent values, as well as progeny tests, are then used to select between the resultant crosses. Material from other breeding programmes can be included in the parental assessments and used in the next cycle of crosses if superior. Finally, in seeking new cultivars, the number of clones on which to practise selection is increased by sowing more true seed of the best progenies, but without selection until the small-plot stage. Traits considered are resistance to late blight [ Phytophthora infestans (Mont.) de Bary] and to the white potato cyst nematode [ Globodera pallida (Stone)], fry colour and tuber yield and appearance, as visually assessed by breeders. The theoretical superiority of the strategy for seeking new cultivars lies in being able to practise between-cross selection for a number of economically important traits within 1 or 2 years of making crosses, something that is not possible on individuals as seedlings in the glasshouse or spaced plants at the seed site. This also means that full-sib family selection can be operated on a 3-year cycle, an improvement on current practice of clonal selection on what is often at least a nine-year cycle. New cultivars can be sought with more confidence from the best progenies in each cycle, and modern methods of rapid multiplication used to reduce the number of clonal generations required to find the best clones.

Most previous studies on cross prediction methods have examined relatively few crosses, particularly in relation to the numbers involved in most breeding programmes. In this paper the feasibility of using cross prediction methods was examined in a practical potato (Solanum tuberosum) breeding scheme by the analyses of progeny from 52 crosses. The variate considered was breeder's preference, a visual assessment made of the harvested tubers to estimate their commercial potential. The results showed that it was possible to identify the superior crosses. Cross prediction based simply on the mean preference scores, averaged over scorers and clones within progenies, estimated on seedlings or first clonal year plants, provided the best estimate of a progeny's performance in the third clonal generation. Predictions based on the expected proportion of clones that would transgress a given target value also provided a good indication of a progeny's potential. The poorest prediction was obtained by using the observed frequency of desirable clones in a progeny sample. The implications for potato breeding are discussed.

Open lung biopsy specimens from two welders and air samples from their workplace environments were examined with the electron probe microanalyzer. X-ray analysis showed that the majority of particles found in the lung tissue from both workers and in the air samples to be composed of varying amounts of iron, chromium, manganese and nickel, the major components of some types of stainless steel. Based upon these analyses, it was concluded that the majority of the particles in both biopsy specimens were a result of the workplace environment.

A modification of a scanning transmission electron microscope specimen holder which permits full viewing of large plastic embedded tissue sections is discussed. The method for producing one-centimeter diameter "giant" grids is explained and the procedure for sample preparation is outlined. The modification aids the microscopist in his evaluation of tissue structural relationships by providing large areas of tissue for examination and reduces significantly the time required to prepare and examine standard 1-2 mm2 electron microscopy tissue sections. Light and electron microscopic evaluations can be made on the same tissue sections.

The fibrogenic potentials of coal and copper slags used as substitutes for silica sand in abrasive blasting operations were assessed in rats. The test animals were given a single pulmonary intralobar instillation of 20 mg of test material and were sacrificed 10 months after dosing. Pulmonary fibrosis was seen in the coal slag-treated rats while no fibrosis was seen in the copper slag-treated animals. Granulomas were seen in the lungs from all treatment groups. The results of the study emphasize the need for bioassay of silica sand replacements for fibrogenic potential in spite of the low free silica contents of these materials.