Lower Respiratory Tract Infections in Pediatric Patients with Severe Neurological Impairments: Clinical Observations and Perspectives in a Palliative Care Unit

Pediatric palliative care (PPC) patients with a severe neurologic impairment (SNI) suffer considerable morbidity and increased mortality from lower respiratory tract infections (LRTIs). The indication and choice of antibiotic therapy for bacterial LRTIs are often challenging given the lack of evidence-based treatment recommendations for this vulnerable patient population. We conducted an observational study before the SARS-CoV-2 pandemic in an eight-bed pediatric palliative care inpatient unit. During two years of surveillance, we diagnosed and treated 33 cases of a bacterial LRTI in patients with an SNI; 5 patients were hospitalized with an LRTI more than once. Two patients died from complications due to LRTIs during hospitalization. Three patients (15%) were colonized with multidrug-resistant organisms. An initial antibiotic treatment failed in one-third of the cases; a successful therapy of the LRTI was achieved with broad-spectrum and extended-spectrum penicillins (n = 13; in combination with β-lactamase inhibitors for n = 5 cases), cephalosporins (n = 13: n = 4 second-generation and n = 9 third-generation cephalosporins; in combination with other substances for n = 5 cases), ciprofloxacin (n = 3), and meropenem plus vancomycin (n = 2) or meropenem (n = 1). A respiratory specimen was obtained in 66.7% of cases with P. aeruginosa, E. coli, and K. pneumoniae accounting for the majority of the detected species. In most cases, there was no definite confirmation that the LRTI was caused by the species detected. The diagnostics and treatment of bacterial LRTIs in PPC patients with an SNI are challenging. The lack of controlled studies and the heterogeneity of this population often necessitate an individual approach. This lack of controlled studies may partly be compensated by a set of diagnostic and antibiotic stewardship criteria

Deep Learning and Inverse Problems

Big data and deep learning are modern buzz words which presently infiltrate all fields of science and technology. These new concepts are impressive in terms of the stunning results they achieve for a large variety of applications. However, the theoretical justification for their success is still very limited. In this snapshot, we highlight some of the very recent mathematical results that are the beginnings of a solid theoretical foundation for the subject

Advanced Control Structures: A Transputer-Based Multi-Robot System

This paper presents the implementation of an efficient motion planner for a two-robot system operating in a unified environment. The distributed formulation of the planner is mapped on a network of T800 transputers and caters for the needs of minimum-time and collision free robot motion in real time. Practical implementation of the planner is reported for two co-ordinated RTX robots and performance results are given of an execution run

Nueva esterasa tolerante a los solventes orgánicos aislada por metagenómica: ideas sobre la clasificación de las esterasas/lipasas

In order to isolate novel organic solvent-tolerant (OST) lipases, a metagenomic library was built using DNA derived from a temperate forest soil sample. A two-step activity-based screening allowed the isolation of a lipolytic clone active in the presence of organic solvents. Sequencing of the plasmid pRBest recovered from the positive clone revealed the presence of a putative lipase/esterase encoding gene. The deduced amino acid sequence (RBest1) contains the conserved lipolytic enzyme signature and is related to the previously described OST lipase from Lysinibacillus sphaericus 205y, which is the sole studied prokaryotic enzyme belonging to the 4.4 / hydrolase subgroup (abH04.04). Both in vivo and in vitro studies of the substrate specificity of RBest1, using triacylglycerols or nitrophenyl-esters, respectively, revealed that the enzyme is highly specific for butyrate (C4) compounds, behaving as an esterase rather than a lipase. The RBest1 esterase was purified and biochemically characterized. The optimal esterase activity was observed at pH 6.5 and at temperatures ranging from 38 to 45 °C. Enzymatic activity, determined by hydrolysis of p nitrophenyl esters, was found to be affected by the presence of different miscible and non-miscible organic solvents, and salts. Noteworthy, RBest1 remains significantly active at high ionic strength. These findings suggest that RBest1 possesses the ability of OST enzymes to molecular adaptation in the presence of organic compounds and resistance of halophilic proteins.Con el fin de aislar nuevas variantes de lipasas tolerantes a solventes orgánicos (OST), se construyó una librería metagenómica a partir de ADN obtenido de una muestra de suelo de bosque templado. A través de un monitoreo en dos etapas, basado en la detección de actividades, se aisló un clon con actividad lipolítica en presencia de solventes orgánicos. La secuenciación del plásmido pRBest recuperado del clon positivo reveló la presencia de un gen codificante de una hipotética lipasa/esterasa. La secuencia deducida de amino ácidos (RBest1) contiene los motivos conservados de enzimas lipolíticas y está relacionada con la lipasa OST previamente descrita de Lysinibacillus sphaericus 205y, que es la única enzima procariota estudiada perteneciente al subgrupo 4.4 de α/β hidrolasas (abH4.04). Estudios in vivo e in vitro sobre la especificidad de sustratos de RBest1, utilizando triacil-gliceroles o p-nitrofenil-ésteres, respectivamente, revelaron que la enzima es altamente específica para compuestos butíricos (C4 ), comportándose como una esterasa y no como una lipasa. La esterasa RBest1 fue purificada y caracterizada bioquímicamente. La actividad óptima de esterasa fue observada a pH 6,5 y las temperaturas óptimas fueron entre 38 y 45 °C. Se estableció que la actividad enzimática, determinada por hidrólisis de p-nitrofenil ésteres, es afectada en presencia de diferentes solventes orgánicos miscibles y no miscibles, y también sales. Notoriamente, RBest1 permanece significativamente activa a elevadas fuerzas iónicas. Estos hallazgos sugieren que RBest1 posee la capacidad de las enzimas OST de la adaptación molecular en presencia de compuestos orgánicos, así como la resistencia de las proteínas halófilasFil: Berlemont, Renaud. Universite de Liege; BélgicaFil: Spee, Olivier. Universite de Liege; BélgicaFil: Delsaute, Maud. Universite de Liege; BélgicaFil: Lara, Yannick. Universite de Liege; BélgicaFil: Schuldes, Jörg. Universitat of Gottingen; AlemaniaFil: Simon, Carola. Universitat of Gottingen; AlemaniaFil: Power, Pablo. Universite de Liege; Bélgica. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Daniel, Rolf. Universitat of Gottingen; AlemaniaFil: Galleni, Moreno. Universite de Liege; Bélgic

Novel organic solvent-tolerant esterase isolated by metagenomics: insights into the lipase/esterase classification

in order to isolate novel organic solvent-tolerant (oSt) lipases, a metagenomic library was built using dna derived from a temperate forest soil sample. a two-step activity-based screening allowed the isolation of a lipolytic clone active in the presence of organic solvents. Sequencing of the plasmid pRBest recovered from the positive clone revealed the presence of a putative lipase/esterase encoding gene. the deduced amino acid sequence (RBest1) contains the conserved lipolytic enzyme signature and is related to the previously described oSt lipase from Lysinibacillus sphaericus 205y, which is the sole studied prokaryotic enzyme belonging to the 4.4 a/b hydrolase subgroup (abh04.04). Both in vivo and in vitro studies of the substrate specificity of RBest1, using triacylglycerols or nitrophenyl-esters, respectively, revealed that the enzyme is highly specific for butyrate (c4) compounds, behaving as an esterase rather than a lipase. the RBest1 esterase was purified and biochemically characterized. the optimal esterase activity was observed at ph 6.5 and at temperatures ranging from 38 to 45 °c. enzymatic activity, determined by hydrolysis of p‐nitrophenyl esters, was found to be affected by the presence of different miscible and non-miscible organic solvents, and salts. noteworthy, RBest1 remains significantly active at high ionic strength. these findings suggest that RBest1 possesses the ability of oSt enzymes to molecular adaptation in the presence of organic compounds and resistance of halophilic proteins

A physiological marker for quantifying differential reproductive investment between the sexes in Yellow-legged gulls (Larus michahellis)

Asymmetry between males and females in the energy they invest initially in reproduction has resulted in the evolution of differing reproductive strategies (caring females vs. competitive males). However, parental care in many birds is shared by both sexes suggesting that male energy expenditure in agonistic behaviors and courtship feeding might compensate female costs of clutch production. Here, we tested the hypothesis that initial investment in reproduction by both sexes in the Yellow-legged Gull (Larus michahellis), a species with biparental care, is similar from a physiological perspective. In this income breeder, female and male reproductive investment during early breeding can be ultimately related to muscular activity (local foraging effort required for clutch production in females and courtship feeding and agonistic behaviors in the case of males). Thus, we evaluated sex-specific patterns of creatine kinase (CK, IU/L) levels in plasma, an indicator of physical effort associated with muscular activity dependent behaviors, through incubation as a reflection of the physiological response of both sexes to the reproductive investment they made up to clutch completion. Raw levels of CK were related to plasma levels of total proteins (TP, g/dL) to account for the differential physiological state of individuals when sampled (i.e. differential dehydratation). Female costs of clutch production were associated with post-laying levels of CK/TP. We grouped females according to their relative investment in clutch production: 17.3% of field metabolic rate; which showed increasing values of CK/TP (24.6, 53.1 and 66.0 IU/g, respectively). Moreover, we found similar CK/TP trends throughout incubation for both sexes (CK/TP = 50.2- [3.3 x days from laying]) suggesting similar physiological responses to reproductive effort and, therefore, analogous sex-specific initial investment. Thus, male investment in agonistic behaviors and courtship feeding apparently equaled female investment in clutch production. The use of CK measurements is revealed as a useful approach to investigating overall investment in reproduction for both sexes, providing further insights into our comprehension of reproductive strategies in seabirds

Non-parametric Heat Map Representation of Flow Cytometry Data: Identifying Cellular Changes Associated With Genetic Immunodeficiency Disorders

Genetic primary immunodeficiency diseases are increasingly recognized, with pathogenic mutations changing the composition of circulating leukocyte subsets measured by flow cytometry (FCM). Discerning changes in multiple subpopulations is challenging, and subtle trends might be missed if traditional reference ranges derived from a control population are applied. We developed an algorithm where centiles were allocated using non-parametric comparison to controls, generating multiparameter heat maps to simultaneously represent all leukocyte subpopulations for inspection of trends within a cohort or segregation with a putative genetic mutation. To illustrate this method, we analyzed patients with Primary Antibody Deficiency (PAD) and kindreds harboring mutations in TNFRSF13B (encoding TACI), CTLA4, and CARD11. In PAD, loss of switched memory B cells (B-SM) was readily demonstrated, but as a continuous, not dichotomous, variable. Expansion of CXCR5+/CD45RA- CD4+ T cells (X5-Th cells) was a prominent feature in PAD, particularly in TACI mutants, and patients with expansion in CD21-lo B cells or transitional B cells were readily apparent. We observed differences between unaffected and affected TACI mutants (increased B cells and CD8+ T-effector memory cells, loss of B-SM cells and non-classical monocytes), cellular signatures that distinguished CTLA4 haploinsufficiency itself (expansion of plasmablasts, activated CD4+ T cells, regulatory T cells, and X5-Th cells) from its clinical expression (B-cell depletion), and those that were associated with CARD11 gain-of-function mutation (decreased CD8+ T effector memory cells, B cells, CD21-lo B cells, B-SM cells, and NK cells). Co-efficients of variation exceeded 30% for 36/54 FCM parameters, but by comparing inter-assay variation with disease-related variation, we ranked each parameter in terms of laboratory precision vs. disease variability, identifying X5-Th cells (and derivatives), naïve, activated, and central memory CD8+ T cells, transitional B cells, memory and SM-B cells, plasmablasts, activated CD4 cells, and total T cells as the 10 most useful cellular parameters. Applying these to cluster analysis of our PAD cohort, we could detect subgroups with the potential to reflect underlying genotypes. Heat mapping of normalized FCM data reveals cellular trends missed by standard reference ranges, identifies changes associating with a phenotype or genotype, and could inform hypotheses regarding pathogenesis of genetic immunodeficiency.This study was supported by a National Health and Medical Research Council (NHMRC) of Australia Centre of Research Excellence (APP1079648)