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1.
J Cheminform ; 9(1): 31, 2017 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-29086051

RESUMEN

Despite the increasingly digital nature of society there are some areas of research that remain firmly rooted in the past; in this case the laboratory notebook, the last remaining paper component of an experiment. Countless electronic laboratory notebooks (ELNs) have been created in an attempt to digitise record keeping processes in the lab, but none of them have become a 'key player' in the ELN market, due to the many adoption barriers that have been identified in previous research and further explored in the user studies presented here. The main issues identified are the cost of the current available ELNs, their ease of use (or lack of it) and their accessibility issues across different devices and operating systems. Evidence suggests that whilst scientists willingly make use of generic notebooking software, spreadsheets and other general office and scientific tools to aid their work, current ELNs are lacking in the required functionality to meet the needs of the researchers. In this paper we present our extensive research and user study results to propose an ELN built upon a pre-existing cloud notebook platform that makes use of accessible popular scientific software and semantic web technologies to help overcome the identified barriers to adoption.

2.
PLoS One ; 10(5): e0125791, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25950799

RESUMEN

BACKGROUND: Glioblastoma multiforme (GBM) is among the most aggressive cancers with a poor prognosis in spite of a plethora of established diagnostic and prognostic biomarkers and treatment modalities. Therefore, the current goal is the detection of novel biomarkers, possibly detectable in the blood of GBM patients that may enable an early diagnosis and are potential therapeutic targets, leading to more efficient interventions. EXPERIMENTAL PROCEDURES: MicroRNA profiling of 734 human and human-associated viral miRNAs was performed on blood plasma samples from 16 healthy individuals and 16 patients with GBM, using the nCounter miRNA Expression Assay Kits. RESULTS: We identified 19 miRNAs with significantly different plasma levels in GBM patients, compared to the healthy individuals group with the difference limited by a factor of 2. Additionally, 11 viral miRNAs were found differentially expressed in plasma of GBM patients and 24 miRNA levels significantly correlated with the patients' survival. Moreover, the overlap between the group of candidate miRNAs for diagnostic biomarkers and the group of miRNAs associated with survival, consisted of ten miRNAs, showing both diagnostic and prognostic potential. Among them, hsa miR 592 and hsa miR 514a 3p have not been previously described in GBM and represent novel candidates for selective biomarkers. The possible signalling, induced by the revealed miRNAs is discussed, including those of viral origin, and in particular those related to the impaired immune response in the progression of GBM. CONCLUSION: The GBM burden is reflected in the alteration of the plasma miRNAs pattern, including viral miRNAs, representing the potential for future clinical application. Therefore proposed biomarker candidate miRNAs should be validated in a larger study of an independent cohort of patients.


Asunto(s)
Neoplasias Encefálicas/sangre , Glioblastoma/sangre , MicroARNs/genética , Análisis de Supervivencia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/virología , Estudios de Casos y Controles , Glioblastoma/genética , Glioblastoma/patología , Glioblastoma/virología , Humanos , MicroARNs/sangre , Pronóstico
3.
J Pharm Biomed Anal ; 91: 151-9, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24463043

RESUMEN

Oligonucleotide aptamers are selected from libraries typically comprising up to 10(15) different sequences by an iterative process of binding, separation, amplification and purification, called SELEX. During this process, the diversity of the oligonucleotide pool decreases until, presumably, only sequences with highest binding affinities towards chosen targets remain. This selection technique is time-consuming, labor-intensive and expensive. Though well posed in principles, the SELEX procedure is noise sensitive, due to amplification of unspecific-binding sequences, and it is not surprising that aptamer selection is often not successful in practice. In view of that, a follow-up of the progress of selection during its course with simple yet reliable methods is necessary. In this paper, we describe five independent assays to estimate the sequence complexity of SELEX pools including qualitative restriction fragment length polymorphism analysis, melting curve analysis, quantitative fluorescence intensity measurements of bound ssDNA, real time PCR quantification and pool dissociation constant analysis during the progress of aptamer selection against streptavidin. Properties and features of each method are discussed and compared. Pool dissociation constant analysis and sequencing serve as reference methods.


Asunto(s)
Aptámeros de Nucleótidos/química , Oligonucleótidos/química , Técnica SELEX de Producción de Aptámeros/métodos , Estreptavidina/química
4.
Biomed Res Int ; 2013: 690415, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23509763

RESUMEN

The adult ovarian surface epithelium has already been proposed as a source of stem cells and germinal cells in the literature, therefore it has been termed the "germinal epithelium". At present more studies have confirmed the presence of stem cells expressing markers of pluripotency in adult mammalian ovaries, including humans. The aim of this study was to isolate a population of stem cells, based on the expression of pluripotency-related stage-specific embryonic antigen-4 (SSEA-4) from adult human ovarian surface epithelium by two different methods: magnetic-activated cell sorting and fluorescence-activated cell sorting. Both methods made it possible to isolate a similar, relatively homogenous population of small, SSEA-4-positive cells with diameters of up to 4 µm from the suspension of cells retrieved by brushing of the ovarian cortex biopsies in reproductive-age and postmenopausal women and in women with premature ovarian failure. The immunocytochemistry and genetic analyses revealed that these small cells--putative stem cells--expressed some primordial germ cell and pluripotency-related markers and might be related to the in vitro development of oocyte-like cells expressing some oocyte-specific transcription factors in the presence of donated follicular fluid with substances important for oocyte growth and development. The stemness of these cells needs to be further researched.


Asunto(s)
Separación Celular/métodos , Epitelio/metabolismo , Células Germinativas/citología , Ovario/citología , Antígenos Embrionarios Específico de Estadio/metabolismo , Células Madre/citología , Adulto , Núcleo Celular/metabolismo , Femenino , Citometría de Flujo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Humanos , Persona de Mediana Edad , Folículo Ovárico/metabolismo , Células Madre Pluripotentes/citología , Posmenopausia , Insuficiencia Ovárica Primaria , Reacción en Cadena en Tiempo Real de la Polimerasa , Adulto Joven
5.
Methods Mol Biol ; 938: 253-68, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22987422

RESUMEN

The real-time PCR detection system for grapevine yellows phytoplasmas described here is composed of two assays for group-specific detection of flavescence dorée (FD) and bois noir (BN) phytoplasmas and a universal phytoplasma assay. It uses hydrolysis minor groove binder probes (TaqMan-MGB). The addition of an assay for amplification of plant DNA co-extracted with phytoplasma DNA provides a further quality control for the DNA extraction and PCR amplification for each sample. The detection system described is reliable, specific, sensitive, and easily applicable to fast, high-throughput diagnosis of grapevine yellows phytoplasmas. In addition to the detection system, an approach for the quantification of phytoplasmas in the sample is described.


Asunto(s)
Phytoplasma/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Biología Computacional/métodos , ADN Bacteriano/genética , Phytoplasma/genética , Enfermedades de las Plantas/microbiología , Reacción en Cadena en Tiempo Real de la Polimerasa/instrumentación
6.
Cell Transplant ; 21(7): 1529-45, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22554389

RESUMEN

In contrast to the application of human mesenchymal stem cells (hMSCs) in regenerative medicine, only a limited number of studies are addressing their use in anticancer therapy. As the latter may represent a new hope to improve the survival of patients with glioblastoma multiformae (GBM), the most common and malignant form of the brain tumors, we aimed to investigate the interactions of hMSCs and GBM cells under in vitro conditions. Four hMSC clones and three different GBM cell lines were used to study their mutual paracrine interactions in cocultures compared to their monocultures, where cells were grown under the same experimental conditions. The effects on cell growth, proliferation, and invasion in Matrigel were quantified. Further, bioinformatics tools were used to relate these results to the data obtained from cytokine macroarrays and cDNA microarrays that revealed proteins and genes significantly involved in cellular cross-talk. We showed that hMSCs are responsible for the impairment of GBM cell invasion and growth, possibly via induction of their senescence. On the other hand, GBM cells inversely affected some of these characteristics in hMSCs. We found CCL2/MCP-1 to be the most significantly regulated chemokine during hMSC and U87-MG paracrine signaling in addition to several chemokines that may account for changed cocultured cells' phenotype by affecting genes associated with proliferation (Pmepa-1, NF-κB, IL-6, IL-1b), invasion (EphB2, Sod2, Pcdh18, Col7A1, Gja1, Mmp1/2), and senescence (Kiaa1199, SerpinB2). As we functionally confirmed the role of CCL2/MCP-1 in GBM cell invasion we thereby propose a novel mechanism of CCL2/MCP-1 antimigratory effects on GBM cells, distinct from its immunomodulatory role. Significant alterations of GBM phenotype in the presence of hMSCs should encourage the studies on the naive hMSC use for GBM treatment.


Asunto(s)
Quimiocinas/metabolismo , Células Madre Mesenquimatosas/citología , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Línea Celular , Movimiento Celular , Proliferación Celular , Senescencia Celular/genética , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Quimiocinas/genética , Técnicas de Cocultivo , Colágeno/química , Regulación hacia Abajo , Combinación de Medicamentos , Glioblastoma/metabolismo , Glioblastoma/patología , Humanos , Inmunomodulación , Laminina/química , Células Madre Mesenquimatosas/inmunología , Células Madre Mesenquimatosas/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Comunicación Paracrina , Fenotipo , Análisis por Matrices de Proteínas , Proteoglicanos/química , Regulación hacia Arriba
7.
PLoS One ; 7(1): e28761, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22253695

RESUMEN

BACKGROUND: Different immunotherapy approaches for the treatment of cancer and autoimmune diseases are being developed and tested in clinical studies worldwide. Their resulting complex experimental data should be properly evaluated, therefore reliable normal healthy control baseline values are indispensable. METHODOLOGY/PRINCIPAL FINDINGS: To assess intra- and inter-individual variability of various biomarkers, peripheral blood of 16 age and gender equilibrated healthy volunteers was sampled on 3 different days within a period of one month. Complex "crossomics" analyses of plasma metabolite profiles, antibody concentrations and lymphocyte subset counts as well as whole genome expression profiling in CD4+T and NK cells were performed. Some of the observed age, gender and BMI dependences are in agreement with the existing knowledge, like negative correlation between sex hormone levels and age or BMI related increase in lipids and soluble sugars. Thus we can assume that the distribution of all 39.743 analysed markers is well representing the normal Caucasoid population. All lymphocyte subsets, 20% of metabolites and less than 10% of genes, were identified as highly variable in our dataset. CONCLUSIONS/SIGNIFICANCE: Our study shows that the intra-individual variability was at least two-fold lower compared to the inter-individual one at all investigated levels, showing the importance of personalised medicine approach from yet another perspective.


Asunto(s)
Técnicas Citológicas/métodos , Salud , Subgrupos Linfocitarios/metabolismo , Población Blanca , Adulto , Anticuerpos/inmunología , Índice de Masa Corporal , Linfocitos T CD4-Positivos/metabolismo , Femenino , Regulación de la Expresión Génica , Humanos , Células Asesinas Naturales/metabolismo , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Análisis de Secuencia por Matrices de Oligonucleótidos , Análisis de Componente Principal , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Reproducibilidad de los Resultados , Adulto Joven
8.
BMC Genomics ; 10: 460, 2009 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-19799775

RESUMEN

BACKGROUND: Phytoplasmas are bacteria without cell walls from the class Mollicutes. They are obligate intracellular plant pathogens which cause diseases in hundreds of economically important plants including the grapevine (Vitis vinifera). Knowledge of their biology and the mechanisms of their interactions with hosts is largely unknown because they are uncultivable and experimentally inaccessible in their hosts. We detail here the global transcriptional profiling in grapevine responses to phytoplasmas. The gene expression patterns were followed in leaf midribs of grapevine cv. 'Chardonnay' naturally infected with a phytoplasma from the stolbur group 16SrXII-A, which is associated with the grapevine yellows disease 'Bois noir'. RESULTS: We established an on field experimental system in a productive vineyard that allowed application of molecular tools in a plant natural environment. Global transcription profiles of infected samples were compared with the healthy ones using microarray datasets and metabolic pathway analysis software (MapMan). The two-year-long experiment revealed that plant genes involved in primary and secondary metabolic pathways were changed in response to infection and that these changes might support phytoplasma nutrition. A hypothesis that phytoplasmas interact with the plant carbohydrate metabolism was proven and some possibilities how the products of this pathway might be utilized by phytoplasmas are discussed. In addition, several photosynthetic genes were largely down-regulated in infected plants, whereas defense genes from the metabolic pathway leading to formation of flavonoids and some PR proteins were significantly induced. Few other genes involved in defense-signaling were differentially expressed in healthy and infected plants. A set of 17 selected genes from several differentially expressed pathways was additionally analyzed with quantitative real-time PCR and confirmed to be suitable for a reliable classification of infected plants and for the characterization of susceptibility features in the field conditions. CONCLUSION: This study revealed some fundamental aspects of grapevine interactions with the stolbur 'Bois noir' phytoplasma in particular and some plant interactions with phytoplasmas in general. In addition, the results of the study will likely have an impact on grape improvement by yielding marker genes that can be used in new diagnostic assays for phytoplasmas or by identifying candidate genes that contribute to the improved properties of grape.


Asunto(s)
Perfilación de la Expresión Génica , Interacciones Huésped-Patógeno , Phytoplasma/fisiología , Enfermedades de las Plantas/genética , Vitis/genética , Metabolismo de los Hidratos de Carbono/genética , Genes de Plantas , Glucólisis/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Fotosíntesis/genética , Enfermedades de las Plantas/microbiología , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , ARN de Planta/genética , Vitis/microbiología
9.
BMC Plant Biol ; 9: 104, 2009 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-19656401

RESUMEN

BACKGROUND: Whole genome transcriptomics analysis is a very powerful approach because it gives an overview of the activity of genes in certain cells or tissue types. However, biological interpretation of such results can be rather tedious. MapMan is a software tool that displays large datasets (e.g. gene expression data) onto diagrams of metabolic pathways or other processes and thus enables easier interpretation of results. The grapevine (Vitis vinifera) genome sequence has recently become available bringing a new dimension into associated research. Two microarray platforms were designed based on the TIGR Gene Index database and used in several physiological studies. RESULTS: To enable easy and effective visualization of those and further experiments, annotation of Vitis vinifera Gene Index (VvGI version 5) to MapMan ontology was set up. Due to specificities of grape physiology, we have created new pictorial representations focusing on three selected pathways: carotenoid pathway, terpenoid pathway and phenylpropanoid pathway, the products of these pathways being important for wine aroma, flavour and colour, as well as plant defence against pathogens. This new tool was validated on Affymetrix microarrays data obtained during berry ripening and it allowed the discovery of new aspects in process regulation. We here also present results on transcriptional profiling of grape plantlets after exposal to the fungal pathogen Eutypa lata using Operon microarrays including visualization of results with MapMan. The data show that the genes induced in infected plants, encode pathogenesis related proteins and enzymes of the flavonoid metabolism, which are well known as being responsive to fungal infection. CONCLUSION: The extension of MapMan ontology to grapevine together with the newly constructed pictorial representations for carotenoid, terpenoid and phenylpropanoid metabolism provide an alternative approach to the analysis of grapevine gene expression experiments performed with Affymetrix or Operon microarrays. MapMan was first validated on an already published dataset and later used to obtain an overview of transcriptional changes in a susceptible grapevine - Eutypa lata interaction at the time of symptoms development, where we showed that the responsive genes belong to families known to be involved in the plant defence towards fungal infection (PR-proteins, enzymes of the phenylpropanoid pathway).


Asunto(s)
Perfilación de la Expresión Génica , Interacciones Huésped-Patógeno , Vitis/genética , Xylariales , Mapeo Cromosómico , Regulación de la Expresión Génica de las Plantas , Análisis de Secuencia por Matrices de Oligonucleótidos , ARN de Planta/genética , Vitis/microbiología
10.
OMICS ; 12(3): 171-82, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18771401

RESUMEN

Due to the great variety of preprocessing tools in two-channel expression microarray data analysis it is difficult to choose the most appropriate one for a given experimental setup. In our study, two independent two-channel inhouse microarray experiments as well as a publicly available dataset were used to investigate the influence of the selection of preprocessing methods (background correction, normalization, and duplicate spots correlation calculation) on the discovery of differentially expressed genes. Here we are showing that both the list of differentially expressed genes and the expression values of selected genes depend significantly on the preprocessing approach applied. The choice of normalization method to be used had the highest impact on the results. We propose a simple but efficient approach to increase the reliability of obtained results, where two normalization methods which are theoretically distinct from one another are used on the same dataset. Then the intersection of results, that is, the lists of differentially expressed genes, is used in order to get a more accurate estimation of the genes that were de facto differentially expressed.


Asunto(s)
Bases de Datos Genéticas , Perfilación de la Expresión Génica/métodos , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Algoritmos , Animales , Expresión Génica , Ratones , Reproducibilidad de los Resultados , Solanum tuberosum/genética , Vitis/genética
11.
Methods Mol Biol ; 451: 583-613, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18370283

RESUMEN

Since their conception in the late 1990s, microarray techniques have become a tool of choice for monitoring pangenomic gene expression. Although there are a large number of variations on the basic methodology the general approach remains standard and involves the comparison of a "test" RNA with a "control" RNA; in this case "healthy" and "virus-infected" plants. The protocol itself can be broken down into five main parts: RNA extraction, cDNA synthesis, hybridization, array scanning, and data analysis. The method presented is optimized for use with arrays based on glass slides spotted with cDNA, in this case 15,264 cDNAs from Solanum tuberosum. The labeling technique presented involves two steps: hybridization of cDNA produced using oligo-dT linker primers to the array and hybridization with a DNA dendrimer reagent comprising sequence complementary to the linker sequence bound to a fluorescent dye. We also present the use of the R environment for data analysis, generating statistical support for differential gene expression observed.


Asunto(s)
Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Virus de Plantas/genética , Plantas/genética , Plantas/virología , ADN Complementario/genética , ADN de Plantas/genética , ADN Viral/genética , Hibridación de Ácido Nucleico/métodos , ARN de Planta/genética , ARN Viral/genética
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