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Mislabeling of cases as well as controls in case-control studies is a frequent source of strong bias in prognostic and diagnostic tests and algorithms. Common data processing methods available to the researchers in the biomedical community do not allow for consistent and robust treatment of labeled data in the situations where both, the case and the control groups, contain a non-negligible proportion of mislabeled data instances. This is an especially prominent issue in studies regarding late-onset conditions, where individuals who may convert to cases may populate the control group, and for screening studies that often have high false-positive/-negative rates. To address this problem, we propose a method for a simultaneous robust inference of Lasso reduced discriminative models and of latent group-specific mislabeling risks, not requiring any exactly labeled data. We apply it to a standard breast cancer imaging dataset and infer the mislabeling probabilities (being rates of false-negative and false-positive core-needle biopsies) together with a small set of simple diagnostic rules, outperforming the state-of-the-art BI-RADS diagnostics on these data. The inferred mislabeling rates for breast cancer biopsies agree with the published purely empirical studies. Applying the method to human genomic data from a healthy-ageing cohort reveals a previously unreported compact combination of single-nucleotide polymorphisms that are strongly associated with a healthy-ageing phenotype for Caucasians. It determines that 7.5 % of Caucasians in the 1000 Genomes dataset (selected as a control group) carry a pattern characteristic of healthy ageing., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Gerber, Pospisil, Sys, Hewel, Torkamani and Horenko.)

Finding reliable discrete approximations of complex systems is a key prerequisite when applying many of the most popular modeling tools. Common discretization approaches (e.g., the very popular K -means clustering) are crucially limited in terms of quality, parallelizability, and cost. We introduce a low-cost improved quality scalable probabilistic approximation (SPA) algorithm, allowing for simultaneous data-driven optimal discretization, feature selection, and prediction. We prove its optimality, parallel efficiency, and a linear scalability of iteration cost. Cross-validated applications of SPA to a range of large realistic data classification and prediction problems reveal marked cost and performance improvements. For example, SPA allows the data-driven next-day predictions of resimulated surface temperatures for Europe with the mean prediction error of 0.75°C on a common PC (being around 40% better in terms of errors and five to six orders of magnitude cheaper than with common computational instruments used by the weather services)., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).)

Background: Given the lack of information concerning the role of Chlamydia trachomatis in male fertility, the aim of this study was to ascertain and analyze the quality of Chlamydiae-positive and -negative semen., Material and Methods: Sperm count was performed according to the 1999 World Health Organization (WHO) laboratory manual for examination of human semen and sperm-cervical mucus interaction, and sperm survival was assessed by a 120-min test. The evaluation of the morphological examination of ejaculates was carried out using the sasmo (strict morphological analysis of ejaculates) computer program. Chlamydiae were detected by immunofluorescent reaction using the Progen Biotechnik GmbH diagnostic set. Fisher's exact test and the chi-quadrate test were used for statistical analysis., Results: Of the total of 627 sperm samples examined, Chlamydiae were detected in 136 cases (21.7%). Sperm analysis showed significant differences between Chlamydiae-positive and -negative samples. The Chlamydiae-contaminated group showed normal sperm morphology 14.4% lower, volume 6.4% lower, concentration 8.3% lower, motility 7.8% and velocity 9.3% lower than in Chlamydiae-negative samples. The average values for normal spermatozoa and motility in the Chlamydiae-positive group were also significantly reduced., Conclusion: Chlamydia trachomatis was found to be a possible factor in sperm pathology. These results could help to elucidate the role of Chlamydia trachomatis in male infertility.

The reduction of atrazine and terbutylazine was preceded by protonation equilibrium. Three protonation sites of the s-triazine molecule determined the structure of the final reduction product. Protonation was investigated by the change of UV-Vis spectra. Two slightly different pKs corresponding to protonation on N5 and N1 heteroatoms were evaluated. The principal reduction pathway involved the cleavage of a chlorine atom. A small quantity of desethylatrazine was detected in the most acidic media.

The investigated compounds were substituted naphtoquinones containing aniline moiety separated from the quinoid system by a methylene bridge. The nature of substituents on both donor and acceptor parts influenced the degree of formation of an internal charge transfer complex. Properties of the internal charge transfer interactions were investigated by voltammetry, spectroscopy, and in situ spectroelectrochemistry. Quantum chemical interpretation of experiments is given.

The authors present a report on the first detection of the strain Dermatophilus congolensis in Czechoslovakia. The strain was isolated from ulcerations on the dorsal part of the foot of a 47-year-old patient who previously worked for several years in Libya. Based on examinations of smears from cultures of an isolated strain and four strains from a collection, from experimental dermatofilosis of a rabbit the authors describe the micromorphology of strains of D. congolensis under a light and electron microscope (transmission an and raster microscope). They describe the colonial morphology, haemolytic properties and in particular detail the haemolytic interaction of strains of D. congolensis with Streptococcus agalactiae, Rhodococcus equi and with strains of S. aureus (monoproducers of beta-haemolysin and delta-haemolysin resp.). They assessed the sensitivity of strains of D. congolensis to some staphylococcal bacteriocin-like substances.

From 1971 to 1976 the author examined by cultivation on Sabouraud glucose agar, 1720 specimens of the most varied materials--skin scales, nails, hair, beard, sputum--obtained from patients suffering from skin problems. In no one single case did he find Candida pulcherrima. However, since 1977 he has found C. pulcherrima to be on an increase. From 1977 to 1984 in 4644 specimens C. pulcherrima was found in 44 cases. 38 strains, i.e. 86%, were isolated from patients with clinical diagnosis of mycotic infection. The most frequent diagnosis was onychomycosis, 36%. Cultivation findings were mostly profuse and massive relative to the number of germs, in some patients even occurring repeatedly. In view of these findings it may be necessary to revise the views purporting the finding of C. pulcherrima from human material to be insignificant.

By means of biotyping we have investigated 150 strains of Staphylococcus aureus isolated from people with dermatologic complaints. We have used six main and three additional biotyping tests. The strains under investigation did not form a closed biotype, on the contrary, they showed a certain biotype plurality. The determination of protein A in 150 strains of S. aureus isolated from dermatologic process of men, 15 strains of S. aureus of bovine origin and 50 strains of Staphylococcus with negative coagulase activity have brought the following results: all strains of S. aureus of skin origin (human strains) contain protein A in various quantities keeping within 2-64 U. Only 2 from 15 s. aureus strains of bovine origin contain protein A and there were none in 50 strains of Staphylococcus with a negative coagulase reaction.