Staphylococcus jettensis sp nov., a coagulase-negative staphylococcal species isolated from human clinical specimens

Eight coagulase-negative, novobiocin-susceptible staphylococcal strains were isolated from human clinical specimens at two different Belgian medical facilities. All strains were non-motile, Gram-stain-positive, catalase-positive cocci. DNA G+C content, peptidoglycan type, menaquinone pattern, the presence of teichoic acid and cellular fatty acid composition were in agreement with the characteristics of species of the genus Staphylococcus. Sequencing of the 16S rRNA gene and four housekeeping genes (dnaJ, tuf, gap and rpoB) demonstrated that these strains constitute a separate taxon within the genus Staphylococcus. Less than 41 % DNA-DNA hybridization with the most closely related species of the genus Staphylococcus (Staphylococcus haemolyticus, Staphylococcus hominis and Staphlococcus lugdunensis) was observed. Key biochemical characteristics that allowed these bacteria to be distinguished from their nearest phylogenetic neighbours are arginine dihydrolase positivity, ornithine decarboxylase negativity and inability to produce acid aerobically from D-mannose, a-lactose and turanose. Acid is produced aerobically from trehalose. Based on these results, a novel species of the genus Staphylococcus is described and named Staphylococcus jettensis sp. nov. The type strain is SE0110(T) (=LMG 26879(T)=CCUG 62657(T)=DSM 26618(T))

Persistence of frequently transmitted drug-resistant HIV-1 variants can be explained by high viral replication capacity

Background: In approximately 10% of newly diagnosed individuals in Europe, HIV-1 variants harboring transmitted drug resistance mutations (TDRM) are detected. For some TDRM it has been shown that they revert to wild type while other mutations persist in the absence of therapy. To understand the mechanisms explaining persistence we investigated the in vivo evolution of frequently transmitted HIV-1 variants and their impact on in vitro replicative capacity. Results: We selected 31 individuals infected with HIV-1 harboring frequently observed TDRM such as M41L or K103N in reverse transcriptase (RT) or M46L in protease. In all these samples, polymorphisms at non-TDRM positions were present at baseline (median protease: 5, RT: 6). Extensive analysis of viral evolution of protease and RT demonstrated that the majority of TDRM (51/55) persisted for at least a year and even up to eight years in the plasma. D

Automated Deep Learning-Based Classification of Wilms Tumor Histopathology

(1) Background: Histopathological assessment of Wilms tumors (WT) is crucial for risk group classification to guide postoperative stratification in chemotherapy pre-treated WT cases. However, due to the heterogeneous nature of the tumor, significant interobserver variation between pathologists in WT diagnosis has been observed, potentially leading to misclassification and suboptimal treatment. We investigated whether artificial intelligence (AI) can contribute to accurate and reproducible histopathological assessment of WT through recognition of individual histopathological tumor components. (2) Methods: We assessed the performance of a deep learning-based AI system in quantifying WT components in hematoxylin and eosin-stained slides by calculating the Sørensen–Dice coefficient for fifteen predefined renal tissue components, including six tumor-related components. We trained the AI system using multiclass annotations from 72 whole-slide images of patients diagnosed with WT. (3) Results: The overall Dice coefficient for all fifteen tissue components was 0.85 and for the six tumor-related components was 0.79. Tumor segmentation worked best to reliably identify necrosis (Dice coefficient 0.98) and blastema (Dice coefficient 0.82). (4) Conclusions: Accurate histopathological classification of WT may be feasible using a digital pathology-based AI system in a national cohort of WT patients

Phenobarbital, midazolam pharmacokinetics, effectiveness, and drug-drug interaction in asphyxiated neonates undergoing therapeutic hypothermia

Background: Phenobarbital and midazolam are commonly used drugs in (near-)term neonates treated with therapeutic hypothermia for hypoxic-ischaemic encephalopathy, for sedation, and/or as anti-epileptic drug. Phenobarbital is an inducer of cytochrome P450 (CYP) 3A, while midazolam is a CYP3A substrate. Therefore, co-treatment with phenobarbital might impact midazolam clearance. Objectives: To assess pharmacokinetics and clinical anti-epileptic effectiveness of phenobarbital and midazolam in asphyxiated neonates and to develop dosing guidelines. Methods: Data were collected in the prospective multicentre PharmaCool study. In the present study, neonates treated with therapeutic hypothermia and receiving midazolam and/or phenobarbital were included. Plasma concentrations of phenobarbital and midazolam including its metabolites were determined in blood samples drawn on days 2–5 after birth. Pharmacokinetic analyses were performed using non-linear mixed effects modelling; clinical effectiveness was defined as no use of additional anti-epileptic drugs. Results: Data were available from 113 (phenobarbital) and 118 (midazolam) neonates; 68 were treated with both medications. Only clearance of 1-hydroxy midazolam was influenced by hypothermia. Phenobarbital co-administration increased midazolam clearance by a factor 2.3 (95% CI 1.9–2.9, p < 0.05). Anticonvulsant effectiveness was 65.5% for phenobarbital and 37.1% for add-on midazolam. Conclusions: Therapeutic hypothermia does not influence clearance of phenobarbital or midazolam in (near-)term neonates with hypoxic-ischaemic encephalopathy. A phenobarbital dose of 30 mg/kg is advised to reach therapeutic concentrations. Phenobarbital co-administration significantly increased midazolam clearance. Should phenobarbital be substituted by non-CYP3A inducers as first-line anticonvulsant, a 50% lower midazolam maintenance dose might be appropriate to avoid excessive exposure during the first days after birth. © 2019 The Author(s) Published by S. Karger AG, Base

RegaDB: Community-driven data management and analysis for infectious diseases

Summary: RegaDB is a free and open source data management and analysis environment for infectious diseases. RegaDB allows clinicians to store, manage and analyse patient data, including viral genetic sequences. Moreover, RegaDB pr

Monografies del Montseny - 35

Des de la primera edició de 1985 comandada per Ramon Bofill Portabella i Antoni Pladevall Font han escrit a les Monografies del Montseny un total de 324 autors diferents, d’arreu del Montseny, molts de Barcelona, però també de la resta del país, inclòs forans. Podeu consultar-los tots a l’índex actualitzat que publiquem cada any. Entre aquest llarg llistat podem trobar escriptors, poetes, científics, polítics, cineastes, esportistes, masovers, propietaris forestals, arquitectes, professors, fotògrafs, llicenciats, advocats, diplomàtics, historiadors, catedràtics, pagesos, filòsofs, guardes forestals, geògrafs, químics, doctors, pintors... Molts dels autors han comandat importants institucions i associacions del nostre país, força són membres de la Reial Acadèmia de Bones Lletres, la Reial Acadèmia Catalana de Belles Arts, l’Institut d’Estudis Catalans... i també hi ha autors que són posseïdors de la Creu de Sant Jordi, la Medalla d’Or de la Generalitat, i els més variats reconeixements. Tot i això, des d’un bon principi els fundadors de Monografies del Montseny van voler que les col·laboracions no fossin tancades a ningú, mentre els treballs tinguessin un mínim de solvència i aportessin valor a la col·lecció, independentment del curriculum vitae particular. Tots els autors han contribuït de manera desinteressada amb un o més articles a la col·lecció Monografies del Montseny; de fet és normal trobar a l’índex històric autors amb una desena de col·laboracions, però aquí cal destacar que Antoni Pladevall Font ha participat a totes les Monografies amb més de cinquanta escrits. Com a trets curiosos podem trobar tres articles d’autors de finals de segle XIX i principis del XX publicats en versió facsímil. Monografies del Montseny acumula avui 591 articles, cosa que les converteixen en “la Bíblia del Montseny”, el lloc necessari on acudir per completar qualsevol recerca sobre un tema montsenyenc. Cada volum s’ha publicat amb una mitja variable d’entre 250-300 pàgines, però en algun cas extraordinari hem arribat fins les 400. Cal tenir en compte que des de l’any 1995 les Monografies incorporen un apèndix amb els versos guardonats als premis de poesia Montseny, i les obres guanyadores del premis de fotografia Montseny mentre va durar el certamen (avui extingit). Això suposa que el conjunt de pàgines publicades durant aquests 35 anys arriba a les 9.295.Postprint (published version

A 2-year retrospective analysis of laboratory testing for activated protein C resistance with a factor V-corrected activated partial thromboplastin time-based method.

The factor V-corrected activated protein C resistance assay is the test of choice to screen for the factor V Leiden mutation. During the past 2 years, local test results with the frequently used Coatest APCR kit were evaluated and compared with the results of DNA analysis, the 'gold standard'. Samples of 278 patients were analysed by both techniques. We were unable to confirm that factor V Leiden carriers can clearly be delineated from normal individuals with the Coatest APCR test. A ratio of 2.0 as the cut-off provides 99.0% sensitivity and 95.4% specificity. To evaluate the lupus anticoagulant interference, we retrospectively analysed 16 lupus anticoagulant-positive patients. In this study, two (12.5%) showed a false-positive activated protein C resistance result. Six out of 16 (37.5%) lupus anticoagulant-positive patients were also carriers of the factor V Leiden mutation. Four out of eight (50%) false-positive activated protein C resistance results presented with an abnormal baseline clotting time. In order to prevent reporting false-positive results, a maximum baseline clotting time (65.8 s) was calculated. A new scheme for interpreting activated protein C resistance ratios was proposed

Bisifusarium dimerum species complex central line-associated bloodstream infection in an immunocompetent patient

Albeit invasive fusariosis is extremely rare in immunocompetent patients, we describe an immunocompetent patient suffering from a central line-associated blood stream infection (CLABSI) and the difficulties in distinguishing between blood culture contamination and clinical significance