Allelic variation of KIR and HLA tunes the cytolytic payload and determines functional hierarchy of NK cell repertoires.

The functionality of natural killer (NK) cells is tuned during education and is associated with remodeling of the lysosomal compartment. We hypothesized that genetic variation in killer cell immunoglobulin-like receptor (KIR) and HLA, which is known to influence the functional strength of NK cells, fine-tunes the payload of effector molecules stored in secretory lysosomes. To address this possibility, we performed a high-resolution analysis of KIR and HLA class I genes in 365 blood donors and linked genotypes to granzyme B loading and functional phenotypes. We found that granzyme B levels varied across individuals but were stable over time in each individual and genetically determined by allelic variation in HLA class I genes. A broad mapping of surface receptors and lysosomal effector molecules revealed that DNAM-1 and granzyme B levels served as robust metric of the functional state in NK cells. Variation in granzyme B levels at rest was tightly linked to the lytic hit and downstream killing of major histocompatibility complex-deficient target cells. Together, these data provide insights into how variation in genetically hardwired receptor pairs tunes the releasable granzyme B pool in NK cells, resulting in predictable hierarchies in global NK cell function.

Effect of mTOR Inhibition with Sirolimus on Natural Killer Cell Reconstitution in Allogeneic Stem Cell Transplantation.

Sirolimus is an inhibitor of the mammalian target of rapamycin (mTOR) and is emerging as a promising component of graft-versus-host disease (GVHD) prophylaxis regimens in the context of allogeneic hematopoietic stem cell transplantation (HSCT). Multiple studies have explored the clinical benefits of adding sirolimus to GVHD prophylaxis; however, detailed immunologic studies have not yet been carried out in this context. Mechanistically, mTOR is at the center of metabolic regulation in T cells and natural killer (NK) cells and is critical for their differentiation to mature effector cells. Therefore, close evaluation of the inhibition of mTOR in the context of immune reconstitution post-HSCT is warranted. In this work, we studied the effect of sirolimus on immune reconstitution using a biobank of longitudinal samples from patients receiving either tacrolimus/sirolimus (TAC/SIR) or cyclosporin A/methotrexate (CSA/MTX) as conventional GVHD prophylaxis. Healthy donor controls, donor graft material, and samples from 28 patients (14 with TAC/SIR, 14 with CSA/MTX) at 3 to 4 weeks and 34 to 39 weeks post- HSCT were collected. Multicolor flow cytometry was used to perform broad immune cell mapping, with a focus on NK cells. NK cell proliferation was evaluated over a 6-day in vitro homeostatic proliferation protocol. Furthermore, in vitro NK cell responses to cytokine stimulation or tumor cells were evaluated. Systems-level assessment of the immune repertoire revealed a deep and prolonged suppression (weeks 34 to 39 post-HSCT) of the naïve CD4 T cell compartment with relative sparing of regulatory T cells and enrichment of CD69+Ki-67+HLA-DR+ CD8 T cells, independent of the type of GVHD prophylaxis. Early after transplantation (weeks 3 to 4), while patients were still on TAC/SIR or CSA/MTX, we found a relative increase in less-differentiated CD56bright NK cells and NKG2A+CD57-KIR- CD56dim NK cells and a distinct loss of CD16 and DNAM-1 expression. Both regimens led to suppressed proliferative responses ex vivo and functional impairment with preferential loss of cytokine responsiveness and IFN-γ production. Patients who received TAC/SIR as GVHD prophylaxis showed delayed NK cell reconstitution with lower overall NK cell counts and fewer CD56bright and NKG2A+ CD56dim NK cells. Treatment with sirolimus-containing regimens generated similar immune cell profiles as conventional prophylaxis; however, the NK cell compartment seemed to be composed of slightly more mature NK cells. These effects were also present after the completion of GVHD prophylaxis, suggesting that mTOR inhibition with sirolimus leaves a lasting imprint on homeostatic proliferation and NK cell reconstitution following HSCT.

Facile preparation of flame-retardant cellulose composite with biodegradable and water resistant properties for electronic device applications.

The aim of the present study is to produce flexible, flame-retardant, water-resistant and biodegradable composite materials. The ultimate goal of this research is to develop simple processes for the production of bio-based materials capable of replacing non-degradable substrates in printed circuit board. Cellulose was chosen as a renewable resource, and dissolved in 1-ethyl-3-methylimidazolium acetate ionic liquid to prepare a cellulosic continuous film. Since flame retardancy is an important criterion for electronic device applications and cellulose is naturally flammable, we incorporated ammonium polyphosphate (APP) as a flame-retardant filler to increase the flame retardancy of the produced materials. The developed material achieved a UL-94 HB rating in the flammability test, while the cellulose sample without APP failed the test. Two hydrophobic agents, ethyl 2-cyanoacrylate and trichloro(octadecyl)silane were applied by a simple dip-coating technique to impart hydrophobicity to the cellulose-APP composites. Dynamic mechanical analysis indicated that the mechanical properties of the cellulosic materials were not significantly affected by the addition of APP or the hydrophobic agents. Moreover, the biodegradability of the cellulosic materials containing APP increased owing to the presence of the cellulase enzyme. The hydrophobic coating slightly decreased the biodegradability of cellulose-APP, but it was still higher than that of pure cellulose film.

Adaptive single-KIR+NKG2C+ NK cells expanded from select superdonors show potent missing-self reactivity and efficiently control HLA-mismatched acute myeloid leukemia.

BACKGROUND: Natural killer (NK) cells hold great promise as a source for allogeneic cell therapy against hematological malignancies, including acute myeloid leukemia (AML). Current treatments are hampered by variability in NK cell subset responses, a limitation which could be circumvented by specific expansion of highly potent single killer immunoglobulin-like receptor (KIR)+NKG2C+ adaptive NK cells to maximize missing-self reactivity. METHODS: We developed a GMP-compliant protocol to expand adaptive NK cells from cryopreserved cells derived from select third-party superdonors, that is, donors harboring large adaptive NK cell subsets with desired KIR specificities at baseline. We studied the adaptive state of the cell product (ADAPT-NK) by flow cytometry and mass cytometry as well as cellular indexing of transcriptomes and epitopes by sequencing (CITE-Seq). We investigated the functional responses of ADAPT-NK cells against a wide range of tumor target cell lines and primary AML samples using flow cytometry and IncuCyte as well as in a mouse model of AML. RESULTS: ADAPT-NK cells were >90% pure with a homogeneous expression of a single self-HLA specific KIR and expanded a median of 470-fold. The ADAPT-NK cells largely retained their adaptive transcriptional signature with activation of effector programs without signs of exhaustion. ADAPT-NK cells showed high degranulation capacity and efficient killing of HLA-C/KIR mismatched tumor cell lines as well as primary leukemic blasts from AML patients. Finally, the expanded adaptive NK cells had preserved robust antibody-dependent cellular cytotoxicity potential and combination of ADAPT-NK cells with an anti-CD16/IL-15/anti-CD33 tri-specific engager led to near-complete killing of resistant CD45dim blast subtypes. CONCLUSIONS: These preclinical data demonstrate the feasibility of off-the-shelf therapy with a non-engineered, yet highly specific, NK cell population with full missing-self recognition capability.

Influence of Calcium Silicate and Hydrophobic Agent Coatings on Thermal, Water Barrier, Mechanical and Biodegradation Properties of Cellulose.

Thin films of cellulose and cellulose-CaSiO3 composites were prepared using 1-ethyl-3-methylimidazolium acetate (EMIMAc) as the dissolution medium and the composites were regenerated from an anti-solvent. The surface hydrophilicity of the resultant cellulose composites was lowered by coating them with three different hydrophobizing agents, specifically, trichloro(octadecyl)silane (TOS), ethyl 2-cyanoacrylate (E2CA) and octadecylphosphonic acid (ODPA), using a simple dip-coating technique. The prepared materials were subjected to flame retardancy, water barrier, thermal, mechanical and biodegradation properties analyses. The addition of CaSiO3 into the cellulose increased the degradation temperature and flame retardant properties of the cellulose. The water barrier property of cellulose-CaSiO3 composites under long term water exposure completely depends on the nature of the hydrophobic agents used for the surface modification process. All of the cellulose composites behaved mechanically as a pure elastic material with a glassy state from room temperature to 250 °C, and from 20% to 70% relative humidity (RH). The presence of the CaSiO3 filler had no effect on the elastic modulus, but it seemed to increase after the TOS surface treatment. Biodegradability of the cellulose was evaluated by enzyme treatments and the influence of CaSiO3 and hydrophobic agents was also derived.

Natural killer cell immunotypes related to COVID-19 disease severity.

Understanding innate immune responses in COVID-19 is important to decipher mechanisms of host responses and interpret disease pathogenesis. Natural killer (NK) cells are innate effector lymphocytes that respond to acute viral infections but might also contribute to immunopathology. Using 28-color flow cytometry, we here reveal strong NK cell activation across distinct subsets in peripheral blood of COVID-19 patients. This pattern was mirrored in scRNA-seq signatures of NK cells in bronchoalveolar lavage from COVID-19 patients. Unsupervised high-dimensional analysis of peripheral blood NK cells furthermore identified distinct NK cell immunotypes that were linked to disease severity. Hallmarks of these immunotypes were high expression of perforin, NKG2C, and Ksp37, reflecting increased presence of adaptive NK cells in circulation of patients with severe disease. Finally, arming of CD56bright NK cells was observed across COVID-19 disease states, driven by a defined protein-protein interaction network of inflammatory soluble factors. This study provides a detailed map of the NK cell activation landscape in COVID-19 disease.

Deciphering Natural Killer Cell Homeostasis.

Natural killer (NK) cells have a central role within the innate immune system, eliminating virally infected, foreign and transformed cells through their natural cytotoxic capacity. Release of their cytotoxic granules is tightly controlled through the balance of a large repertoire of inhibitory and activating receptors, and it is the unique combination of these receptors expressed by individual cells that confers immense diversity both in phenotype and functionality. The diverse, yet unique, NK cell repertoire within an individual is surprisingly stable over time considering the constant renewal of these cells at steady state. Here we give an overview of NK cell differentiation and discuss metabolic requirements, intra-lineage plasticity and transcriptional reprogramming during IL-15-driven homeostatic proliferation. New insights into the regulation of NK cell differentiation and homeostasis could pave the way for the successful implementation of NK cell-based immunotherapy against cancer.

Epilepsy for primary health care: a cost-effective Latin American E-learning initiative.

A lack of neurologists in Latin America forces primary health care providers to manage epilepsy. With the main goal of improving diagnostic and therapeutic management of patients with epilepsy through training of physicians in the primary health care level, the International League Against Epilepsy Education Commission (2013-2017) created a low-cost, regional, virtual course. The course, set-up in Moodle platform, was structured in eight modules, each lasting for a week. Teaching was based on written didactic material, videos, and interactive discussions, both in Spanish and Portuguese. Topics included epidemiology, diagnosis, classification, treatment, prognosis, social issues, and epilepsy policies. Each course was limited to 50 participants and priority was given to general practitioners. Certification was given to those approving the final examination. Since 2015, five courses have been developed, involving 143 participants from 17 countries and 21 tutors. Of the participants, 61% worked in primary health care services. A total of 129 participants (90%) completed the course, and 110 submitted the final examination with an approval rate of 95%. From 85 participants completing the course evaluation, 98% would recommend the course to other colleagues, and 99% showed interest in taking other similar courses. High self-confidence for the management of patients with epilepsy increased from 21% at baseline to 73% after the course. The online course on epilepsy for primary care physicians in Latin America was shown to be a cost-effective course, with good retention and excellent approval rates. Our current challenges include periodic updating, complete self-sustainability, and exploring different strategies to reach our target audience more effectively.

Easy reuse of magnetic cross-linked enzyme aggregates of lipase B from Candida antarctica to obtain biodiesel from Chlorella vulgaris lipids.

In this work, magnetic cross-linked enzyme aggregates (mCLEAs) of CALB (lipase B from Candida antarctica) were prepared and characterized. Moreover, a method for an easy, sustainable and economic extraction of lipids from nitrogen-starved cells of Chlorella vulgaris var L3 was developed. Then, the extracted lipids (oils and free fatty acids, FFAs) were converted to biodiesel using mCLEAs and chemical acid catalysis. Among several lipid extraction methods, saponification was selected given the amount of wet microalgal biomass it can process per unit of time, its low market value, and because it allows for the use of less toxic solvents. A biodiesel conversion of 80.2 ± 4.4% was obtained by chemical catalysis (1 h at 100°C) using FFAs and methanol as the alkyl donor. However, a biodiesel conversion of more than 90% (3 h at 30°C) was obtained using mCLEAs and methanol. Both chemical and enzymatic catalysts gave biodiesel with similar fatty acid alkyl ester (FAAE) composition. Methanol, at 15% (v/v) or higher concentration, caused a decrease of lipase activity and a concomitant increase in the size of mCLEA aggregates (up to 2 µm), as measured by dynamic light scattering (DLS). The magnetic character of the novel biocatalyst permits its easy recovery and reuse, for at least ten consecutive catalytic cycles (retaining 90% of the initial biodiesel conversion), using mild reaction conditions and environmentally-friendly solvents.

A screen-printed paper microbial fuel cell biosensor for detection of toxic compounds in water.

Access to safe drinking water is a human right, crucial to combat inequalities, reduce poverty and allow sustainable development. In many areas of the world, however, this right is not guaranteed, in part because of the lack of easily deployable diagnostic tools. Low-cost and simple methods to test water supplies onsite can protect vulnerable communities from the impact of contaminants in drinking water. Ideally such devices would also be easy to dispose of so as to leave no trace, or have a detrimental effect on the environment. To this aim, we here report the first paper microbial fuel cell (pMFC) fabricated by screen-printing biodegradable carbon-based electrodes onto a single sheet of paper, and demonstrate its use as a shock sensor for bioactive compounds (e.g. formaldehyde) in water. We also show a simple route to enhance the sensor performance by folding back-to-back two pMFCs electrically connected in parallel. This promising proof of concept work can lead to a revolutionizing way of testing water at point of use, which is not only green, easy-to-operate and rapid, but is also affordable to all.

Estudio de variantes de los genes BDNF, COMT, DAT1 y SERT en niños colombianos con déficit de atención / Study of genetic variants in the BDNF, COMT, DAT1 and SERT genes in Colombian children with attention deficit disorder

Resumen Introducción: El trastorno por déficit de atención e hiperactividad (TDAH) es una perturbación con elevada prevalencia en población infantil de Bogotá. Entre las causas de este trastorno se encuentran factores genéticos y ambientales, pero pocos estudios han tratado de abordar el componente genético en población colombiana. Objetivos: Realizar un estudio de asociación genética entre diferentes polimorfismos y el TDAH en la población de Bogotá. Métodos: Múltiples polimorfismos de los genes DAT1, SERT, COMT y BDNF fueron genotipificados empleando las técnicas de PCR convencional y RFLP en 97 tríos de Bogotá. El test de desequilibrio de trasmisión (TDT) se empleó para determinar la asociación entre las diferentes variantes y el TDAH. Resultados: El análisis de TDT no identificó una transmisión preferencial de alelos de ninguna de las variantes estudiadas. Conclusiones: Nuestros resultados indican que la etiología del TDAH es heterogénea e involucra diversos factores genéticos. Futuros estudios enfocados en otros polimorfismos candidatos en una muestra más grande ayudarán a comprender el TDAH en la población colombiana.

Abstract Background: Attention deficit and hyperactive disorder (ADHD) is highly prevalent among children in Bogota City. Both genetic and environmental factors play a very important role in the etiology of ADHD. However, to date few studies have addressed the association of genetic variants and ADHD in the Colombian population. Objectives: To test the genetic association between polymorphisms in the DAT1, HTTLPR, COMT and BDNF genes and ADHD in a sample from Bogota City. Methods: We genotyped the most common polymorphisms in DAT1, SERT, COMT and BDNF genes associated with ADHD using conventional PCR followed by restriction fragment length polymorphism (RFLP) in 97 trios recruited in a medical center in Bogota. The transmission disequilibrium test (TDT) was used to determine the association between such genetic variants and ADHD. Results: The TDT analysis showed that no individual allele of any variant studied has a preferential transmission. Conclusions: Our results suggest that the etiology of the ADHD maybe complex and involves several genetic factors. Further studies in other candidate polymorphisms in a larger sample size will improve our knowledge of the ADHD in Colombian population.

[Study of genetic variants in the BDNF, COMT, DAT1 and SERT genes in Colombian children with attention deficit disorder]. / Estudio de variantes de los genes BDNF, COMT, DAT1 y SERT en niños colombianos con déficit de atención.

BACKGROUND: Attention deficit and hyperactive disorder (ADHD) is highly prevalent among children in Bogota City. Both genetic and environmental factors play a very important role in the etiology of ADHD. However, to date few studies have addressed the association of genetic variants and ADHD in the Colombian population. OBJECTIVES: To test the genetic association between polymorphisms in the DAT1, HTTLPR, COMT and BDNF genes and ADHD in a sample from Bogota City. METHODS: We genotyped the most common polymorphisms in DAT1, SERT, COMT and BDNF genes associated with ADHD using conventional PCR followed by restriction fragment length polymorphism (RFLP) in 97 trios recruited in a medical center in Bogota. The transmission disequilibrium test (TDT) was used to determine the association between such genetic variants and ADHD. RESULTS: The TDT analysis showed that no individual allele of any variant studied has a preferential transmission. CONCLUSIONS: Our results suggest that the etiology of the ADHD may be complex and involves several genetic factors. Further studies in other candidate polymorphisms in a larger sample size will improve our knowledge of the ADHD in Colombian population.

[Colombian Guidelines of clinical practice for the use of immunoglobulins in the treatment of replacement and immunomodulation]. / Guía colombiana de práctica clínica para el uso de inmonuglobulinas en el tratamiento de reemplazo e inmunomodulación.

Immunoglobulins are heterodimeric proteins composed of 2 heavy chains and 2 light chains. Human immunoglobulin G (IgG) is a plasma derivative and contains more than 95% of IgG. The composition of IgG subclasses is similar to that of normal human plasma. Immunoglobulin therapy was first introduced more than 50 years ago, and its use has been described in numerous diseases. In Colombia, the importance of this immunomodulatory resource prompted the need for clinical practice guidelines to be available for its use. For this reason, a multidisciplinary group of experts was brought together and distributed in working groups, by specialties, in order to develop an initial manuscript. Systematic literature searches were undertaken; identified evidences were evaluated and classified to support a preliminary draft that was discussed, analyzed and amended. Recommendations were issued on the use of intravenous immunoglobulin in pathologies that include primary and secondary immunodeficiencies, autoimmune diseas es, neurological disorders, infections, transplants and miscellaneous conditions; grades were assigned to each one of them according to the GRADE system. The final result translated into recommendations that are put forth with the purpose to inform, guide and support on optimal use of this immunomodulatory resource.

Las inmunoglobulinas son proteínas heterodiméricas compuestas de 2 cadenas pesadas y 2 cadenas ligeras. La inmunoglobulina G humana es un derivado del plasma y contiene más de 95 % de IgG. La composición de las subclases de IgG es similar a la del plasma humano normal. El tratamiento con inmunoglobulina comenzó hace más de 50 años y su uso se ha descrito en numerosas enfermedades. En Colombia, la importancia de este recurso inmunomodulador condujo a la necesidad de contar con una guía de práctica clínica para su uso, para lo cual se reunió un grupo multidisciplinario de expertos, quienes se distribuyeron en mesas de trabajo, por especialidad, para redactar un texto base. Se llevaron a cabo búsquedas bibliográficas sistemáticas; las evidencias identificadas se valoraron y clasificaron para sustentar un texto preliminar que fue discutido, analizado y corregido. Se emitieron recomendaciones de uso de la inmunoglobulina intravenosa en patologías que abarcan inmunodeficiencias primarias y secundarias, enfermedades autoinmunes, alteraciones neurológicas, infecciones, trasplantes y enfermedades misceláneas; se asignaron calificaciones según el sistema GRADE para cada una. El resultado final se tradujo en las recomendaciones que se presentan con la finalidad de informar, orientar y apoyar en el uso óptimo de dicho recurso inmunomodulador.

Caracterización de la cámara anterior con la pentacam hr en los pacientes atendidos en la clínica de optometria de la universidad santo tomás

Objetivo: Caracterizar la cámara anterior de 1140 exámenes de topografía con la Pentacam HR clasificando el ángulo, profundidad y volumen. Métodos: Estudio observacional descriptivo retrospectivo. Los criterios de inclusión fueron: hombres, mujeres y exámenes con especificación de la calidad correcta y reproducible. Resultados: Mediana de la profundidad de la cámara anterior: en mujeres 2.98 mm y hombres 3.07 mm, mediana del ángulo de la cámara anterior: mujeres de 37.4° y hombres 39.7° y mediana del volumen de la cámara anterior: mujeres 160 mm3 y hombres 171 mm3; las tres variables con diferencias estadísticamente significativas por sexo. Conclusión: La población estudio tiene baja frecuencia de cámara anterior estrecha (13,8%), de ángulo cerrado (16,7%) y volumen de la cámara anterior disminuido (15,9%); pero específicamente, los pacientes mayores de 44 años y las mujeres tienen menor profundidad, menor ángulo y menor volumen de la cámara anterior.

Objective: The purpose of this research was to characterize the anterior chamber of 1140 topography exams with Pentacam HR, classifying the angle, depth and volume. Method: Retrospective descriptive observational study. Inclusion criteria: male, female and exams with replicable and proper quality specifications. Results: Anterior chamber depth median (2.98 mm in females and 3.07 mm in males); anterior chamber angle median (37.4° in females and 39.7° in males); anterior chamber volume median (160 mm3 in females and 171 mm3 in males). All three variables with statistically significant differences by gender. Conclusion: The population studied shows low frequency of narrow anterior chamber (13.8%), angle-closure (16.7%) and reduced volume of anterior chamber (15.9%); but specifically, patients over 44 and women have less depth, a more acute angle and lower volume of anterior chamber.

Objetivo: O objetivo deste trabalho foi caracterizar a câmara anterior de 1140 exames de topografia com a Pentacam HR, classificando o ângulo, profundidade e volume. Método: Estudo retrospectivo observacional descritivo. Critérios de inclusão: homens, mulheres e exames com as especificações de qualidade replicáveis e adequadas. Resultados: Mediana da profundidade da câmara anterior (2,98 mm em mulheres e 3,07 mm em homens); mediana do ângulo da câmara anterior (37,4° em mulheres e 39,7 ° em homens); mediana do volume da câmara anterior (160 mm3 em mulheres e 171 mm3 em homens). Todas as três variáveis apresentaram diferenças estatisticamente significativas por sexo. Conclusão: A população estudada apresenta baixa freqüência de câmara anterior estreita (13,8%), de ângulo fechado (16,7%) e volume reduzido de câmara anterior (15,9%); mas especificamente, pacientes com mais de 44 anos e mulheres têm menor profundidade, um ângulo mais agudo e menor volume de câmara anterior.

Magnetic biocatalysts and their uses to obtain biodiesel and biosurfactants.

Nanobiocatalysis, as the synergistic combination of nanotechnology and biocatalysis, is rapidly emerging as a new frontier of biotechnology. The use of immobilized enzymes in industrial applications often presents advantages over their soluble counterparts, mainly in view of stability, reusability and simpler operational processing. Because of their singular properties, such as biocompatibility, large and modifiable surface and easy recovery, iron oxide magnetic nanoparticles (MNPs) are attractive super-paramagnetic materials that serve as a support for enzyme immobilization and facilitate separations by applying an external magnetic field. Cross-linked enzyme aggregates (CLEAs) have several benefits in the context of industrial applications since they can be cheaply and easily prepared from unpurified enzyme extracts and show improved storage and operational stability against denaturation by heat and organic solvents. In this work, by using the aforementioned advantages of MNPs of magnetite and CLEAs, we prepared two robust magnetically-separable types of nanobiocatalysts by binding either soluble enzyme onto the surface of MNPs functionalized with amino groups or by cross-linking aggregates of enzyme among them and to MNPs to obtain magnetic CLEAs. For this purpose the lipase B of Candida antarctica (CALB) was used. The hydrolytic and biosynthetic activities of the resulting magnetic nanobiocatalysts were assessed in aqueous and organic media. Thus, the hydrolysis of triglycerides and the transesterification reactions to synthesize biodiesel and biosurfactants were studied using magnetic CLEAs of CALB. The efficiency and easy performance of this magnetic biocatalysis validates this proof of concept and sets the basis for the application of magnetic CLEAs at industrial scale.

Ataxia aguda en la población pediátrica de la Fundación Hospital de laMisericordia 2009-2013 / Acute Ataxia in the Pediatric Population of the Fundacion Hospital de la Misericordia 2009-2013

La ataxia aguda (AA) en la población pediátrica generalmente es secundaria a disfunción cerebelosade origen inmunológico. En urgencias, la rápida detección de patologías de menor frecuencia y mayorgravedad que requieren tratamiento específico es prioridad.Objetivos: Describir la etiología de la AA en los pacientes valorados por Neuropediatría en la FundaciónHospital la Misericordia entre los años 2009 y 2013.Métodos y Materiales: Estudio descriptivo tipo serie de casos. Revisión retrospectiva de historias clínicas depacientes de 1 mes a 18 años con diagnóstico definitivo de AA. Análisis de datos mediante SPSS 21, medidasde tendencia central, Kaplan Meier y prueba de Log Rank.Resultados: Se recopilaron 48 casos, de los cuales el 91,67% fue de origen cerebeloso. El diagnóstico etiológicomás frecuente fue cerebelitis o romboencefalitis viral en 25%, seguido de intoxicación aguda y post infecciosa(20,5% cada una). En cuanto a pronóstico, el 60.4 % tuvo una recuperación completa, siendo esta más rápidaen la ataxia postinfecciosa, tóxica y post traumática.Discusión: La disfunción cerebelosa fue la causa más frecuente de ataxia, los diagnósticos etiológicos principalesfueron ataxia de origen infeccioso y post infeccioso, el antecedente de infección 1 a 30 días antes del iniciode los síntomas neurológicos fue positivo en 41.67 %, lo que sugiere un importante papel de la inmunidad.Conclusiones: La mayoría de las ataxias agudas son secundarias a disfunción cerebelosa infecciosa, inmunológicao tóxica; el pronóstico depende de la etiología y generalmente es benigno...

A ubiquitous sensor network platform for integrating smart devices into the semantic sensor web.

Ongoing Sensor Web developments make a growing amount of heterogeneous sensor data available to smart devices. This is generating an increasing demand for homogeneous mechanisms to access, publish and share real-world information. This paper discusses, first, an architectural solution based on Next Generation Networks: a pilot Telco Ubiquitous Sensor Network (USN) Platform that embeds several OGC® Sensor Web services. This platform has already been deployed in large scale projects. Second, the USN-Platform is extended to explore a first approach to Semantic Sensor Web principles and technologies, so that smart devices can access Sensor Web data, allowing them also to share richer (semantically interpreted) information. An experimental scenario is presented: a smart car that consumes and produces real-world information which is integrated into the Semantic Sensor Web through a Telco USN-Platform. Performance tests revealed that observation publishing times with our experimental system were well within limits compatible with the adequate operation of smart safety assistance systems in vehicles. On the other hand, response times for complex queries on large repositories may be inappropriate for rapid reaction needs.

Multiplex ligation-dependent probe amplification to subtelomeric rearrangements in idiopathic intellectual disability in Colombia.

BACKGROUND: A cause cannot be determined in 30% to 50% of patients with intellectual disability. Determining the etiology of intellectual disability is important and useful for pediatric neurologists, geneticists, pediatricians, and patients' families because it allows assessment of recurrence risk, appropriate genetic counseling, and focus on treatment options and prognosis. This study aims to determine the prevalence, origin, and characterization of subtelomeric rearrangements through the Multiplex Ligation-Dependent Probe Amplification method in pediatric patients with idiopathic intellectual disability. METHODS: A cross-sectional descriptive study was undertaken with patients seen in consultation at the neuropediatrics or genetic service of the Central Military Hospital, the Mercy' Hospital, or the Genetics Institute National University of Colombia. Patients were diagnosed with idiopathic intellectual disability between December 2010 and September 2011 and underwent a complete medical history, physical examination, and assessment to rule out other etiologies of intellectual disability. Then we applied the genetic test of Multiplex Ligation-Dependent Probe Amplification to each patient's sample of peripheral blood to determine subtelomeric rearrangements. RESULTS: We studied a group of 119 patients with idiopathic intellectual disability; Multiplex Ligation-Dependent Probe Amplification showed subtelomeric rearrangements in five. In the group with subtelomeric rearrangements, the most frequent results were de novo rearrangements (80%), deletion type (60%), moderate and severe intellectual disability (80%), minor phenotypic abnormalities (80%), and family history of neurological disorders (80%). No dependence relationship was observed between subtelomeric rearrangements and family history of neurological disorders, family history of intellectual disability, severity of intellectual disability, phenotypic abnormalities, and consanguinity. CONCLUSIONS: This study determined a prevalence of subtelomeric rearrangements of 4.2% in a group of Colombian pediatric patients with idiopathic intellectual disability using the genetic test Multiplex Ligation-Dependent Probe Amplification.

Magnetic Cross-Linked Enzyme Aggregates (mCLEAs) of Candida antarctica lipase: an efficient and stable biocatalyst for biodiesel synthesis.

Enzyme-catalyzed production of biodiesel is the object of extensive research due to the global shortage of fossil fuels and increased environmental concerns. Herein we report the preparation and main characteristics of a novel biocatalyst consisting of Cross-Linked Enzyme Aggregates (CLEAs) of Candida antarctica lipase B (CALB) which are covalently bound to magnetic nanoparticles, and tackle its use for the synthesis of biodiesel from non-edible vegetable and waste frying oils. For this purpose, insolubilized CALB was covalently cross-linked to magnetic nanoparticles of magnetite which the surface was functionalized with -NH2 groups. The resulting biocatalyst combines the relevant catalytic properties of CLEAs (as great stability and feasibility for their reutilization) and the magnetic character, and thus the final product (mCLEAs) are superparamagnetic particles of a robust catalyst which is more stable than the free enzyme, easily recoverable from the reaction medium and reusable for new catalytic cycles. We have studied the main properties of this biocatalyst and we have assessed its utility to catalyze transesterification reactions to obtain biodiesel from non-edible vegetable oils including unrefined soybean, jatropha and cameline, as well as waste frying oil. Using 1% mCLEAs (w/w of oil) conversions near 80% were routinely obtained at 30°C after 24 h of reaction, this value rising to 92% after 72 h. Moreover, the magnetic biocatalyst can be easily recovered from the reaction mixture and reused for at least ten consecutive cycles of 24 h without apparent loss of activity. The obtained results suggest that mCLEAs prepared from CALB can become a powerful biocatalyst for application at industrial scale with better performance than those currently available.

[Detection of subtelomeric rearrangements due to MLPA in paediatric patients with refractory epilepsy in Colombia: the role of the CHL1 gene in pharmacoresistance]. / Detección de rearreglos subteloméricos por MLPA en pacientes pediátricos con epilepsia refractaria en Colombia: papel del gen CHL1 en la farmacorresistencia.

INTRODUCTION. Epilepsy is a neurological disorder characterised by a predisposition to the recurrence of seizures of distinct causation and with variable clinical manifestations. Up to 40% of patients do not manage to control their seizures with the first anticonvulsive drug and the addition of a second pharmaceutical affords control in only another 11%. Given the aetiological heterogeneity of pharmacoresistance, it has been suggested that the presence of genomic disorders in patients with refractoriness could be elements worthy of analysis when it comes to estimating the alteration in the pharmacokinetic or pharmacodynamic profiles of these patients. AIM. To detect the presence of subtelomeric rearrangements in Colombian paediatric patients with refractory epilepsy. PATIENTS AND METHODS. The multiplex ligation-dependent probe amplification (MLPA) technique was used to evaluate the presence of cytogenetically non-visible chromosome aberrations in subtelomeric regions of 113 patients diagnosed with refractory epilepsy from three national referral centres in Colombia. RESULTS. Subtelomeric chromosome aberrations were detected in 0.9% of patients corresponding to a duplication of locus 3p26.3 in gene CHL1. CONCLUSIONS. This study suggests the use of the MLPA methodology to detect subtelomeric rearrangements that may be associated with phenotypes of refractoriness in epileptic patients.

TITLE: Deteccion de rearreglos subtelomericos por MLPA en pacientes pediatricos con epilepsia refractaria en Colombia: papel del gen CHL1 en la farmacorresistencia.Introduccion. La epilepsia es un trastorno neurologico caracterizado por una predisposicion a la recurrencia de crisis convulsivas de etiologia diversa y con manifestaciones clinicas variables. Hasta un 40% de los pacientes no logra el control de las crisis con el primer tratamiento anticonvulsionante y la adicion de un segundo farmaco logra el control de solo un 11% adicional. Dada la heterogeneidad etiologica de la farmacorresistencia se ha propuesto que la presencia de trastornos genomicos en pacientes con refractariedad podrian ser elementos de analisis a la hora de estimar la alteracion en los perfiles farmacocineticos o farmacodinamicos de estos pacientes. Objetivo. Detectar la presencia de rearreglos subtelomericos en pacientes pediatricos colombianos con epilepsia refractaria. Pacientes y metodos. Se utilizo la tecnica de amplificacion multiple de sondas dependiente de ligamiento (MLPA) para evaluar la presencia de aberraciones cromosomicas no visibles citogeneticamente en las regiones subtelomericas de 113 pacientes diagnosticados con epilepsia refractaria provenientes de tres centros de referencia nacional en Colombia. Resultados. Se detectaron aberraciones cromosomicas subtelomericas en el 0,9% de los pacientes correspondientes a una duplicacion del locus 3p26.3 en el gen CHL1. Conclusion. Este estudio plantea el uso de la metodologia de MLPA para la deteccion de rearreglos subtelomericos que puedan asociarse con fenotipos de refractariedad en pacientes epilepticos.