Synthetic phosphoethanolamine-modified oligosaccharides reveal the importance of glycan length and substitution in biofilm-inspired assemblies

Bacterial biofilm matrices are nanocomposites of proteins and polysaccharides with remarkable mechanical properties. Efforts understanding and tuning the protein component have been extensive, whereas the polysaccharide part remained mostly overlooked. The discovery of phosphoethanolamine (pEtN) modified cellulose in E. coli biofilms revealed that polysaccharide functionalization alters the biofilm properties. To date, the pattern of pEtN cellulose and its mode of interactions with proteins remains elusive. Herein, we report a model system based on synthetic epitomes to explore the role of pEtN in biofilm-inspired assemblies. Nine pEtN-modified oligosaccharides were synthesized with full control over the length, degree and pattern of pEtN substitution. The oligomers were co-assembled with a representative peptide, triggering the formation of fibers in a length dependent manner. We discovered that the pEtN pattern modulates the adhesion of biofilm-inspired matrices, while the peptide component controls its stiffness. Unnatural oligosaccharides tune or disrupt the assembly morphology, revealing interesting targets for polysaccharide engineering to develop tunable bio-inspired materials

Automated laser-transfer synthesis of high-density microarrays for infectious disease screening

Abstract Laser-induced forward transfer (LIFT) is a rapid laser-patterning technique for high-throughput combinatorial synthesis directly on glass slides. A lack of automation and precision limited LIFT applications to simple proof-of-concept syntheses of fewer than 100 compounds. Here, we report an automated synthesis instrument that combines laser transfer and robotics for parallel synthesis in a microarray format with up to 10000 individual reactions/cm2. An optimized pipeline for amide bond formation is the basis for preparing complex peptide microarrays with thousands of different sequences in high yield with high reproducibility. The resulting peptide arrays are of higher quality than commercial peptide arrays. More than 4800 15-residue peptides resembling the entire Ebola virus proteome on a microarray were synthesized to study the antibody response of an Ebola virus infection survivor. We identified known and unknown epitopes that serve now as a basis for Ebola diagnostic development. The versatility and precision of the synthesizer is demonstrated by in situ synthesis of fluorescent molecules via Schiff base reaction and multi-step patterning of precisely definable amounts of fluorophores. This automated laser transfer synthesis approach opens new avenues for high-throughput chemical synthesis and biological screening

Automated Laser‐Transfer Synthesis of High‐Density Microarrays for Infectious Disease Screening

Laser-induced forward transfer (LIFT) is a rapid laser-patterning technique for high-throughput combinatorial synthesis directly on glass slides. A lack of automation and precision limits LIFT applications to simple proof-of-concept syntheses of fewer than 100 compounds. Here, an automated synthesis instrument is reported that combines laser transfer and robotics for parallel synthesis in a microarray format with up to 10 000 individual reactions cm−2. An optimized pipeline for amide bond formation is the basis for preparing complex peptide microarrays with thousands of different sequences in high yield with high reproducibility. The resulting peptide arrays are of higher quality than commercial peptide arrays. More than 4800 15-residue peptides resembling the entire Ebola virus proteome on a microarray are synthesized to study the antibody response of an Ebola virus infection survivor. Known and unknown epitopes that serve now as a basis for Ebola diagnostic development are identified. The versatility and precision of the synthesizer is demonstrated by in situ synthesis of fluorescent molecules via Schiff base reaction and multi-step patterning of precisely definable amounts of fluorophores. This automated laser transfer synthesis approach opens new avenues for high-throughput chemical synthesis and biological screening

Diferencias clínicas y hematimétricas en pacientes con trombocitemia esencial y mutación para el gen de la calreticulina

Abstract [PB-090] Introducción: La identificación de la mutación somática en el gen CALR ha supuesto un avance diagnóstico en las neoplasias mieloproliferativas crónicas. Una cuarta parte de los pacientes (ptes) con trombocitemia esencial (TE) presenta dicha mutación, diferenciando dos variantes: la CALR tipo 1 (deleciones) y tipo 2 (inserciones). La TE mutada por CALR podría tratarse no solo de una entidad distinta a nivel molecular, sino también a nivel clínico-analítico. Métodos: Estudio descriptivo y prospectivo unicéntrico. Se incluyen 95 pacientes con TE diagnosticados en el Hospital Miguel Servet. Se analizan variables demográficas, características clínicas y hematimétricas en función de la biología molecular del paciente, establecimiento las diferencias observadas entre los pacientes con mutación JAK-2 y CALR (tipo 1 y tipo 2). Resultados: 35 eran hombres y 60 mujeres. Del total de pacientes, 55 presentaban la mutación JAK-2 (57, 89%), 22 la mutación CALR (23, 15%) (tipo 1: 12 ptes (46, 15%) y tipo 2: 10 ptes (38, 46%)), 5 la mutación MPL (5, 2%) y 9 eran triples negativos (9, 4%). Los ptes con TE mutada con CALR eran más jóvenes que los JAK-2, mediana de edad 65 años (29-84) y 72 años (40-96) respectivamente. Al diagnóstico, las cifras de hemoglobina y leucocitos en ptes JAK-2 eran superiores (mediana 14, 6 g/dL y 9, 30. 10³/µL) frente a CALR tipo 1 (mediana 14, 1 g/dL y 7, 78.10³/µL) y tipo 2 (14, 4 g/dL y 7, 80.10³/µL) y presentaban un recuento menor de plaquetas (mediana 744.10³/µL) frente a CALR tipo 1 (mediana 836. 10³/µL) y tipo 2 (mediana 916.10³/µL). Todos los pacientes CALR presentaban niveles normales de eritropoyetina mientras que un 18% JAK-2 presentaban niveles descendidos. 17 ptes (12, 72%) JAK-2, 3 ptes (25%) CALR tipo 1 y 1 pte (10%) CALR tipo 2 presentaban esplenomegalia. Presentaron episodio trombótico previo al diagnóstico: 5 ptes JAK- 2 (9%), de éstos 5 ptes eran hipertensos y 2 dislipémicos, 1 pte CALR tipo 1 (8, 3%), era hipertenso, dislipémico y fumador y ninguno CALR tipo 2, 1 pte era hipertenso. Tras el diagnóstico 1 pte JAK2 presentó nuevo episodio trombótico posteriormente. Al diagnóstico, 41 pacientes JAK-2 se les realizó biopsia ósea (74, 5%) con reticulina grado 1: 11 ptes (26, 82%), grado 2: 3 ptes (7, 3%) y grado 3: 0 ptes; a 11 ptes CALR tipo 1 (91, 6%) con reticulina grado 1: 3 ptes (27, 27%) y grado 2-3: 0 ptes; a 7 pacientes CALR tipo 2 (70%) con reticulina tipo 1: 3 ptes (44, 85%) y grado 2-3: 0 ptes. Conclusiones: La TE con mutación CALR parece comportarse de manera diferente en térmicos de características biológicas, hematológicas y clínicas frente a la mutación JAK2. Afecta a individuos relativamente jóvenes y se caracteriza por un recuento de plaquetas mayor pero con un riesgo trombótico inferior, especialmente los pacientes CALR tipo 2. Aunque en nuestra serie no encontramos grandes diferencias entre los subtipos de CALR, probablemente por el escaso número de ptes, creemos que ampliando la muestra existan diferencias entre ambos subgrupos que podrían implicar diferentes algoritmos terapéuticos

Parámetros de detección precoz de infección fúngica por aspergillus en el paciente hematológico

PO-267 Introducción: La infección fúngica invasiva (IFI) por Aspergillus es una de las principales micosis invasivas en el paciente hematológico y una importante causa de morbimortalidad. Es más frecuente en pacientes con leucemia aguda mieloide, trasplante de progenitores hematopoyéticos alogénico, enfermedad injerto contra receptor activa o neutropenia prolongada. Supone un reto diagnóstico, siendo preciso el empleo de múltiples técnicas microbiológicas y radiológicas. Avances recientes en el diagnóstico, en la profilaxos y en el tratamiento antifúngico precoz, han reducido considerablemente la mortalidad asociada a esta infección. Objetivos: Determinar si los marcadores diagnósticos empleados en la práctica clínica habitual permiten un diagnóstico precoz de IFI, si la determinación de bismetilgliotoxina (bmGT) en suero permite un diagnóstico precoz en pacientes con antígeno de galactomanano (AGA) en suero negativo y la exactitud diagnóstica de estos marcadores. ..

Overview of recent TJ-II stellarator results

The main results obtained in the TJ-II stellarator in the last two years are reported. The most important topics investigated have been modelling and validation of impurity transport, validation of gyrokinetic simulations, turbulence characterisation, effect of magnetic configuration on transport, fuelling with pellet injection, fast particles and liquid metal plasma facing components. As regards impurity transport research, a number of working lines exploring several recently discovered effects have been developed: the effect of tangential drifts on stellarator neoclassical transport, the impurity flux driven by electric fields tangent to magnetic surfaces and attempts of experimental validation with Doppler reflectometry of the variation of the radial electric field on the flux surface. Concerning gyrokinetic simulations, two validation activities have been performed, the comparison with measurements of zonal flow relaxation in pellet-induced fast transients and the comparison with experimental poloidal variation of fluctuations amplitude. The impact of radial electric fields on turbulence spreading in the edge and scrape-off layer has been also experimentally characterized using a 2D Langmuir probe array. Another remarkable piece of work has been the investigation of the radial propagation of small temperature perturbations using transfer entropy. Research on the physics and modelling of plasma core fuelling with pellet and tracer-encapsulated solid-pellet injection has produced also relevant results. Neutral beam injection driven Alfvénic activity and its possible control by electron cyclotron current drive has been examined as well in TJ-II. Finally, recent results on alternative plasma facing components based on liquid metals are also presented. ISSN:0029-5515 ISSN:1741-432

Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

Automated Laser-Transfer Synthesis of High-Density Microarrays for Infectious Disease Screening

Laser-induced forward transfer (LIFT) is a rapid laser-patterning technique for high-throughput combinatorial synthesis directly on glass slides. A lack of automation and precision limits LIFT applications to simple proof-of-concept syntheses of fewer than 100 compounds. Here, an automated synthesis instrument is reported that combines laser transfer and robotics for parallel synthesis in a microarray format with up to 10 000 individual reactions cm−2. An optimized pipeline for amide bond formation is the basis for preparing complex peptide microarrays with thousands of different sequences in high yield with high reproducibility. The resulting peptide arrays are of higher quality than commercial peptide arrays. More than 4800 15-residue peptides resembling the entire Ebola virus proteome on a microarray are synthesized to study the antibody response of an Ebola virus infection survivor. Known and unknown epitopes that serve now as a basis for Ebola diagnostic development are identified. The versatility and precision of the synthesizer is demonstrated by in situ synthesis of fluorescent molecules via Schiff base reaction and multi-step patterning of precisely definable amounts of fluorophores. This automated laser transfer synthesis approach opens new avenues for high-throughput chemical synthesis and biological screening

Metal Nitride Cluster Fullerene M 3 N@C 80 (M = Y, Sc) Based Dyads: Synthesis, and Electrochemical, Theoretical and Photophysical Studies

Abstract: The first pyrrolidine and cyclopropane derivatives of the trimetallic nitride templated (TNT) endohedral metallofullerenes I h -Sc 3 N@C 80 and I h -Y 3 N@C 80 connected to an electrondonor unit (i.e., tetrathiafulvalene, phthalocyanine or ferrocene) were successfully prepared by 1,3-dipolar cycloaddition reactions of azomethine ylides and Bingel-Hirsch-type reactions. Electrochemical studies confirmed the formation of th