Humoral and cellular immunity in sarcoidosis

The Kveim reaction was studied in vivo in 50 patients with sarcoidosis. Commonwealth Serum Laboratories Kveim material and a new Danish Kveim material gave 14 and 8 positive reactions respectively, as well as 6 and 8 equivocal reactions. Forty-six of the patients were also tested in vitro for cell mediated immunity to the Danish Kveim material, using both the leucocyte migration agarose technique and the capillary technique. No significant migration inhibition or stimulation were found. A tuberculin skin test was performed in 49 of the patients, and in 45 a dinitrochlorobenzene sensitivity titer was determined. Both tests revealed a depression of the cell mediated immunity. The serum levels of immunoglobulins IgG, IgA, IgM, IgD, and IgE were determined. The serum of each patient was also examined to determine if organ-non-specific and granulocyte-specific antinuclear factors of IgG class, antibodies against native DNA, rheumatoid factor, mitochondrial antibodies, antibodies against thyroid cytoplasm, and parietal cell antibodies were present. IgG levels were above normal in 28 patients; IgE was above normal in 10 patients, 4 of whom were atopics or had an atopic disposition. Organ-non-specific antinuclear factors were present in 17 patients.     

Predictive Regularity Representations in Violation Detection and Auditory Stream Segregation: From Conceptual to Computational Models

Predictive accounts of perception have received increasing attention in the past 20 years. Detecting violations of auditory regularities, as reflected by the Mismatch Negativity (MMN) auditory event-related potential, is amongst the phenomena seamlessly fitting this approach. Largely based on the MMN literature, we propose a psychological conceptual framework called the Auditory Event Representation System (AERS), which is based on the assumption that auditory regularity violation detection and the formation of auditory perceptual objects are based on the same predictive regularity representations. Based on this notion, a computational model of auditory stream segregation, called CHAINS, has been developed. In CHAINS, the auditory sensory event representation of each incoming sound is considered for being the continuation of likely combinations of the preceding sounds in the sequence, thus providing alternative interpretations of the auditory input. Detecting repeating patterns allows predicting upcoming sound events, thus providing a test and potential support for the corresponding interpretation. Alternative interpretations continuously compete for perceptual dominance. In this paper, we briefly describe AERS and deduce some general constraints from this conceptual model. We then go on to illustrate how these constraints are computationally specified in CHAINS.     

Measuring target detection performance in paradigms with high event rates

ObjectivesCombining behavioral and neurophysiological measurements inevitably implies mutual constraints, such as when the neurophysiological measurement requires fast-paced stimulus presentation and hence the attribution of a behavioral response to a particular preceding stimulus becomes ambiguous. We develop and test a method for validly assessing behavioral detection performance in spite of this ambiguity.MethodsWe examine four approaches taken in the literature to treat such situations. We analytically derive a new variant of computing the classical parameters of signal detection theory, hit and false alarm rates, adapted to fast-paced paradigms.ResultsEach of the previous approaches shows specific shortcomings (susceptibility towards response window choice, biased estimates of behavioral detection performance). Superior performance of our new approach is demonstrated for both simulated and empirical behavioral data. Further evidence is provided by reliable correspondence between behavioral performance and the N2b component as an electrophysiological indicator of target detection.ConclusionsThe appropriateness of our approach is substantiated by both theoretical and empirical arguments.SignificanceWe demonstrate an easy-to-implement solution for measuring target detection performance independent of the rate of event presentation. Thus overcoming the measurement bias of previous approaches, our method will help to clarify the behavioral relevance of different measures of cortical activation.     

An observational study of slimming behavior in Denmark in 1992 and 1998

OBJECTIVE: To elucidate how frequent weight-loss attempts are made, the methods used to achieve weight loss, and the extent to which the outcome is positive. RESEARCH METHODS AND PROCEDURES: Two independent interviews were conducted in 1992 and in 1998, each with 1200 randomly selected adult subjects. Each survey was designed to ensure an equal distribution of age, gender, and geographical regions in Denmark. RESULTS: The proportion of subjects having attempted weight loss did not change from 1992 to 1998, although the prevalence of overweight and obesity increased from 1992 (overweight, 30%; obesity, 6%) to 1998 (overweight, 35%; obesity, 8%). Almost twice as many women (61%) than men (32%) had attempted weight loss (p < 0.0001). Slimming occurred more often in subjects <50 years (51%) than >50 years (39%) (p < 0.0001), although overweight and obesity were more frequent in the elderly. Over-the-counter diet pills or meal replacements were associated with a negative outcome of slimming treatment (p < 0.0001). DISCUSSION: Approximately half of all adult Danes have attempted weight loss, particularly women and individuals <50 years. This finding is inconsistent with the fact that overweight and obesity are more prevalent in men and in individuals >50 years. Changes in habitual diet and increased physical activity are the most prevalent modes of slimming, whereas the use of over-the-counter diet pills or meal replacements has decreased from 1992 to 1998. This development may have a positive impact on future body- weight-management strategies.     

Association of chromosome 19q13.2-3 haplotypes with basal cell carcinoma: tentative delineation of an involved region using data for single nucleotide polymorphisms in two cohorts

We have previously used single nucleotide polymorphisms to detect an association of basal cell carcinoma (BCC) in Caucasian Americans and Danes with the genome region 19q13.2-3, which contains several genes involved in the nucleotide excision repair of DNA. In this exploratory paper we have extended the data and used them in a chromosomal scan. The results indicate the presence of a gene variation modulating the risk of developing BSS in a submegabase region including and surrounding the gene RAI. Specifically, persons that are homozygous for the haplotype RAI intron 1(A) RAI exon 6(A) appear at increased risk for BCC. In addition, we have looked for possible synergisms between all pairs of markers. We find that a marker in GLTSCR1, presumably separated from RAI by several million bases, supplements the most significant marker in RAI in separating cases from controls, which may suggest the presence of an independent, risk-modulating variation in this second gene region.     

Lignocaine gel used for lubrication of intranasal and endotracheal tubes in premature neonates

Bendixen D, Halvorsen A-C, Hjelt K, Flachs H. Lignocaine gel used for lubrication of intranasal and endotracheal tubes in premature neonates. Acta Prediatr 1994;83:493–7. Stockholm. ISSN 0803–5253
In this study, we have measured the plasma concentration of lignocaine and its metabolite, monoethylglycinxylidin, in 19 premature neonates (gestational age 33 weeks) when lignocaine gel was used for lubrication of an intranasal tube (during continuous positive airway pressure treatment) or an endotracheal tube (for intubation). We did not find any correlation between plasma concentration of lignocaine or monoethylglycinxylidin and weight of the infant (range 795–2530 g). None of the neonates had toxic levels of lignocaine. One neonate had an exceptionally high but not toxic plasma level of monoethylglycinxylidin. However, this neonate had been treated for severe seizures with an iv infusion of lignocaine up to 13 h before the study. In conclusion, we found it safe to use moderate amounts of lignocaine (i.e. 0.3 ml/kg of lignocaine gel 20 mg/ml) for lubricating both intranasal and endotracheal tubes.