RESUMO
Long non-coding RNAs (lncRNAs) are identified as important regulatory molecules related to diverse biological processes. In recent years, benefiting from the rapid development of high-throughput sequencing technology, RNA-seq, and analysis methods, more lncRNAs have been identified and discovered in various plant and algal species. However, so far, only limited studies related to algal lncRNAs are available. Volvox carteri f. nagariensis is the best multicellular model organism to study in developmental and evolutionary biology; therefore, studying and increasing information about this species is important. This study identified lncRNAs in the multicellular green algae Volvox carteri and 1457 lncRNAs were reported, using RNA-seq data and with the help of bioinformatics tools and software. This study investigated the effect of low-dose UV-B radiation on changes in the expression profile of lncRNAs in gonidial and somatic cells. The differential expression of lncRNAs was analyzed between the treatment (UV-B) and the control (WL) groups in gonidial and somatic cells. A total of 37 and 26 lncRNAs with significant differential expression in gonidial and somatic cells, respectively, were reported. Co-expression analysis between the lncRNAs and their neighbor protein-coding genes (in the interval of ± 10 Kb) was accomplished. In gonidial cells, 184 genes with a positive correlation and 13 genes with a negative correlation (greater than 0.95), and in somatic cells, 174 genes with a positive correlation, and 18 genes with a negative correlation were detected. Functional analysis of neighboring coding genes was also performed based on gene ontology. The results of the current work may help gain deeper insight into the regulation of gene expression in the studied model organism, Volvox carteri.(AU)
Assuntos
Humanos , Volvox/metabolismo , Sequência de Bases , Clorófitas/microbiologia , Evolução Biológica , RNA Longo não Codificante/genética , Microbiologia , Técnicas Microbiológicas , Clorófitas/genética , Clorófitas/metabolismo , RNA Longo não Codificante/metabolismoRESUMO
Kluyveromyces marxianus is expected to be used in the production of yeast extracts due to its good fermentation ability and nutritional properties. Yeast autolysis is a key process to produce yeast extract and vacuum negative pressure stress can be used as an effective way to assist autolysis. However, the molecular mechanism of initiating Kluyveromyces marxianus autolysis induced by vacuum negative pressure and the higher temperature is still unclear. In this study, RNA-seq technology was performed mainly to analyze autolytic processes in Kluyveromyces marxianus strains. Considerable differentially expressed genes (DEGs) of downregulation were significantly enriched in 7 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways related to synthesis and transport of RNA and ribosome, which indicated that abnormal protein translations had already occurred in autolytic process. Interestingly, due to obvious change of related DEGs, endoplasmic reticulum-associated degradation (ERAD) and autophagy were activated and cell wall integrity pathway was hindered. Under the continuous influence of the external stress environment, the long-term changes of the above pathways triggered a vicious circle of gradual damage to yeast cells, which is the main cause of yeast autolysis. These results may provide important clues for the in-depth interpretation of the yeast autolytic mechanism.(AU)
Assuntos
Humanos , Autólise , Sequência de Bases , Kluyveromyces , Leveduras , Fermentação , Microbiologia , Técnicas MicrobiológicasRESUMO
Glycosylation of cell surface proteins regulates critical cellular functions, including invasion and metastasis in cancer cells. Emerging evidence has shown that microRNAs (miRNAs) are involved in regulating both the glycosylation modifications on cell surface and the progression of cancer. In this study, we investigated the role of miR-9 in alfa -2,6-linked sialylation and the metastasis of mouse hepatocellular carcinoma (HCC). According to array-based miRNA expression profiling data of HCC cell lines Hepa1-6, Hca-P, and Hca-F with different lymphatic metastatic capacities, reverse correlation was found between miR-9 expression levels and the metastatic potential in these HCC cells. Additionally, Beta-galactoside alfa -2,6-sialyltransferase 1 (St6gal1) expression level is associated negatively with miR-9 and positively with metastatic potential. Bioinformatics analysis indicated that miR-9 could target St6gal1, which was verified by luciferase reporter assays. miR-9 overexpression reduced expression of St6gal1, which subsequently suppressed HCC cells metastatic potential. Moreover, upregulation of miR-9 could inhibit integrin-Beta1/FAK-mediated cell motility and migration signaling in mouse HCC cells. Together, our results suggest that miR-9 could act as a tumor suppressor and regulate mouse HCC cells migration and invasion by inhibiting the alfa-2,6-linked sialylation. This finding may provide insight into the relationship between abnormal miRNA expression and aberrant cell surface glycosylation during tumor lymphatic metastasis
Assuntos
Humanos , Animais , Camundongos , Carcinoma Hepatocelular/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/genética , Neoplasias Hepáticas Experimentais/genética , MicroRNAs/genética , Sialiltransferases/genética , Sequência de Bases , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Movimento Celular , Linhagem Celular Tumoral , Biologia Computacional , Quinase 1 de Adesão Focal , Glicosilação , Luciferases , Metástase LinfáticaRESUMO
El microbioma humano es un ecosistema interno constituido por el hombre y los microorganismos que en él conviven, microorganismos esenciales para mantener su salud, pues junto con el sistema inmunológico protegen frente a patógenos invasores y mantienen la salud. La base de la microbiología tradicional ha sido el cultivo bacteriano, sin embargo la mayoría de los microorganismos observables en la naturaleza, no se cultivan mediante técnicas habituales, por ello en la actualidad, la era molecular ha permitido identificar estos microorganismos en base a su huella genética, gracias a la metagenómica. La subunidad 16S del ARN ribosomal es considerada como la diana universal para la identificación bacteriana a partir del ADN, con la ayuda de la secuenciación. El método de Sanger o secuenciación de primera generación terminó imponiéndose por su sencillez y precisión, posteriormente se desarrolló la segunda generación, o de alto rendimiento capaz de generar cientos de miles de reacciones de secuencias de manera más rápida y económica, sin embargo, es la secuenciación de tercera generación, la que lleva al límite los avances de la nanotecnología. Con la utilización del gen de referencia, las técnicas de secuenciación masiva y las herramientas bioinformáticas para el tratamiento de datos, se ha podido conseguir una información sobre el microbioma humano, con un nivel de detalle sin precedente en cuanto a taxonomía y función de los microorganismos, lo que ha supuesto una autentica revolución no solo en su conocimiento sino también en su implicación en la salud o de enfermedad del ser humano (AU)
The human microbiome is an internal ecosystem that refers to the community of microorganisms that populate the human body. These microorganisms are essential to support his health, because the interaction between the host immune system and microorganisms, provide the host with protection against pathogens, and contributes to the preservation of health. Bacteriological culture has been the basis for traditional microbiology; however, most of the bacterial forms observed in nature cannot be isolated with laboratory culture methods. At present, metagenomic applies a suite of genomic technologies, where the microorganisms are identified by their genomic fingerprint. The 16S rRNA subunit is considered as the universal target for bacterial identification from DNA with the aid of sequencing. Sanger sequencing technology had a great impact on the first generation sequencing due to its simplicity and precision. Platforms high-throughput known as second generation sequencing technologies are capable to generate hundreds of thousands of sequence reactions in a faster and economic way. However, thanks to the third generation sequencing the greatest advances in nanotechnology have been made. Using the reference gene, the massive sequencing techniques and bioinformatics tools used for the data processing, there has been an important development of the human microbiome, achieving an unprecedented detail level on the taxonomy and microbial function. This has meant an authentic revolution not only in their knowledge but also in their involvement in the health or illness of the human being (AU)
Assuntos
Humanos , Microbiota/genética , Microbiota/fisiologia , Sequenciamento de Nucleotídeos em Larga Escala , RNA Ribossômico/genética , Metagenômica/métodos , Sequência de Bases/genética , Biodiversidade , Biomarcadores/análise , RNA Ribossômico 16S/análise , RNA Ribossômico 16SRESUMO
No disponible
Assuntos
História da Medicina , Projeto Genoma Humano/história , Previsões , História da Farmácia , Extratos Vegetais/história , Sequência de Bases , Hereditariedade , Eugenia (Ciência)/tendênciasRESUMO
La secuenciación masiva (o de nueva generación) del ácido desoxirribonucleico ha revolucionado el diagnóstico genético. Esta tecnología reduce el trabajo y el coste necesarios para el análisis simultáneo de muchos genes, lo que hace que más pacientes puedan acceder a un estudio genético. En el caso de la miocardiopatía hipertrófica, se ha pasado de analizar los tres genes principales (MYH7, MYBPC3, TNNT2) a secuenciar más de veinte genes. A pesar de las ventajas que esto representa en términos de información, muchos pacientes presentan variantes de significado incierto (fundamentalmente cambios de aminoácido) que están también en al menos uno de los controles cuyo genoma se ha secuenciado. Esta situación aboca a un «callejón sin salida» en caso de que no se pueda demostrar que esas variantes segregan con la enfermedad en la familia del paciente. En ausencia de evidencia clara de que sean realmente patogénicas, no se podrán emplear para un consejo genético fiable a los familiares del paciente. Finalmente, la secuenciación masiva también permite identificar nuevos genes candidatos pero, una vez más, el problema de las variantes de significado incierto limita el éxito de estos estudios (AU)
Massive DNA sequencing, also known as next-generation sequencing, has revolutionized genetic diagnosis. This technology has reduced the effort and cost needed to analyze several genes simultaneously and has made genetic evaluation available to a larger number of patients. In hypertrophic cardiomyopathy, genetic analysis has increased from the 3 main genes implicated in the disease (MYH7, MYBPC3, TNNT2) to sequencing of more than 20 related genes. Despite the advantages of acquiring this additional information, many patients show variants of uncertain significance (mainly amino acid changes), which may also be present in at least 1 healthy control undergoing genome sequencing. This will be a dead-end situation unless the variant can be demonstrated to be associated with the disease in the patient's family. In the absence of clear evidence that these variants are truly pathogenic, they cannot be used for reliable genetic counselling in family members. Massive sequencing also enables identification of new candidate genes, but again, the problem of variants of uncertain significance limits the success of these assessments (AU)
Assuntos
Humanos , Cardiomiopatia Hipertrófica/genética , Sequência de Bases/genética , Filaminas/genética , Marcadores Genéticos/genética , Predisposição Genética para Doença/genéticaRESUMO
Mediante el análisis de un caso de discordancia entre el nivel de alfa-1-antitripsina (AAT) en suero y el genotipo para los alelos deficientes más frecuentemente asociados al déficit de AAT (PI*S y PI*Z), se ha identificado por primera vez fuera de Portugal un paciente que presenta el alelo nulo PI*Q0ourém, el cual ha sido asociado a casos graves de enfisema pulmonar. La puesta a punto de un ensayo clínico para la detección de la mutación c.1130insT, basado en sondas fluorescentes de tipo HybProbe(R), ha permitido detectar otros 4 sujetos portadores del alelo PI*Q0ourém entre un conjunto de 43 pacientes que mostraban niveles séricos de AAT anormalmente bajos atendiendo a su genotipo para los alelos PI*S y PI*Z. Puesto que 4 de los 5 casos se concentran en una misma localidad de la isla de La Palma (España), es aconsejable realizar estudios genéticos familiares y quizás un cribado poblacional localizado
By analysis of a case of discrepancy between serum alpha-1-antitrypsin (AAT) level and genotype for the most common defective alleles associated with AAT deficiency (PI*S and PI*Z), a patient carrying the allele PI*Q0ourém has been identified for the first time outside of Portugal. This null allele has been implicated in cases of severe pulmonary emphysema. After developing a clinical assay for detection of c.1130insT mutation, based on fluorescent probes (HybProbe(R)), another 4 carriers of PI*Q0ourém allele were identified among 43 patients with abnormally low serum AAT levels based on their genotypes for PI*S and PI*Z alleles. Since 4 out 5 cases are from the same locality (La Palma Island, Spain), it is advisable to conduct genetic analyses of affected families and, possibly, a focused population screening
Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Técnicas de Genotipagem , alfa 1-Antitripsina/genética , Deficiência de alfa 1-Antitripsina/genética , Alelos , Sequência de Bases , Degradação Associada com o Retículo Endoplasmático , Dados de Sequência Molecular , Fenótipo , Análise de Sequência de DNA , Espanha , alfa 1-Antitripsina/análiseRESUMO
Fundamento y objetivo: El control de la diabetes mellitus se realiza mediante la determinación de hemoglobina glucosilada (HbA1c) por cromatografía líquida de alta resolución. Algunas variantes estructurales de la hemoglobina (Hb) son conocidas por causar interferencia analítica en la medición de la HbA1c. Pacientes y métodos: En este estudio se ha caracterizado una nueva variante de Hb en 4 pacientes, que se detectó al realizarse un control de HbA1c. Resultados: La secuenciación selectiva del gen α1 mostró una mutación responsable del cambio de ácido aspártico (Asp) por asparagina (Asn) en el codón 64. El cambio de Asp por Asn no produce ninguna alteración funcional de la Hb y se comporta como una hemoglobinopatía silente. Conclusión: Las variantes estructurales de la Hb se pueden detectar durante la medición de la HbA1c y pueden alterar sus valores. Estos casos, aunque poco frecuentes, requieren examinar a fondo los cromatogramas para detectar posibles interferencias (AU)
Background and objective: The glycated hemoglobin (HbA1c) test by high performance liquid chromatography is a useful tool for the follow-up of diabetes mellitus patients. Some structural hemoglobin (Hb) variants are known to cause interference in the analytical measurement of HbA1c. Patients and methods: In this study, it has been characterized a new Hb variant in 4 patients during their regular control of HbA1c. Results: Selective α1 gene sequencing showed a mutation GAC > AAC at codon 64 within exon 2. This produces a change of aspartic acid (Asp) by asparagine (Asn) that does not produce any functional alteration so the resultant molecule behaves as a silent hemoglobinopathy. Conclusion: The structural Hb variants can be detected during the analysis of HbA1c and may alter its values. Though rare, this occurrence signals the need to being aware when measuring HbA1 (AU)
Assuntos
Humanos , Diabetes Mellitus/fisiopatologia , Hemoglobinas Glicadas/análise , Hemoglobinopatias/fisiopatologia , Sequência de Bases/genética , Cromatografia Líquida de Alta PressãoRESUMO
La patentabilidad de los genes humanos fue desde el comienzo de la discusión de la Directiva sobre Protección Jurídica de las invenciones biotecnológicas, una cuestión que suscitó debates entre los políticos, los científicos, los juristas y la propia sociedad civil. Si bien, la Directiva 98/44 trató de solucionar el asunto al establecer que para admitir la patentabilidad de los genes humanos se debe conocer que función cumplen qué proteína codifican, como requisito imprescindible para probar la aplicación industrial. Sin embargo, tras la sentencia de 13 de junio de 2013, del Tribunal Supremos de los EEUU en el caso Association for Molecular Pathology et al. Versus Myriad Genetics Ind, se ha reabierto el debate sobre esta cuestión. Si bien hay varias cuestiones a considerar, ya que las patentes de secuencias de ADN han representado un importante incentivo para aumentar el interés en la biotecnología aplicada a la salud humana. Y por otro lado, estamos ante un cambio de paradigma en la I+D de las compañías biofamacéuticas, y se ha pasado de un modelo de investigación in house a un modelo de open inovation, de colaboración entre grandes corporaciones con pymes biotecnológicas y centros de investigación públicos y privados (...) (AU)
The patentability of human genes was from the begining of the discussion concerning the directive on the legal protectionof biotechnologicalinventions an issue that provoked debates among politicians, scientistis, lawyers and civil an society itself. Although Directive 98/44 tried to settle the matter by stating that to support the patentability of human genes, it should know what role they fulfill, which protein they encode, all of this as an essential requirement to test its industrial application. However, following the judgment of 13 June 2013 (Supreme Court of the United States of America in the Case of Association for Molecular Pathology et al versus Myriad Genetics. Inc) the debate on this issue has been reopene. There are several issues to be considered, taking into account that the patents on DNA & Gene Sequences have played an important incentive to increase the interest in biotechonology applied to human health. On the other hand, this is a paradigm shift in the R & D of biopharmaceutical companies, and it has moved from an in house research model to a model of open innovation, a model of collaboration between large corporations with biotech SMEs and public and private research centers. This model of innovation, impacts on the issue of the industrial property, and therefor it will be necessary to clearly define what each party brings to the relationship and how they are expected to share the results. But all of this, with the ultimate goal that the patients have access to treatments and medications most innovative, safe and effective (AU)
Assuntos
Humanos , Sequência de Bases , Análise de Sequência de DNA , Patentes como Assunto/legislação & jurisprudência , Temas Bioéticos , Projeto Genoma Humano/legislação & jurisprudênciaRESUMO
Resumen. En estos momentos se encuentra en plena expansión la llamada secuenciación paralela o de siguiente generación -next generation sequencing (NGS)-, que establece un salto de varios órdenes de magnitud en la longitud de los fragmentos secuenciados y la rapidez de su secuenciación. La NGS permite la secuenciación de un genoma humano completo en el tiempo y el coste económico de secuenciar dos o tres genes grandes con la técnica de Sanger. Mediante la NGS se pasa de examinar genes específicos seleccionados mediante estudio del fenotipo a explorar genomas enteros de grupos humanos o de otras especies. Esto está permitiendo conocer no sólo cómo es un genoma individual, sino cómo cambia el genoma humano de persona a persona, cómo difieren los genomas entre diferentes grupos humanos, e incluso cómo difiere el genoma de un tumor respecto del genoma sano del huésped (AU)
Summary. At the present time the so-called parallel or next generation sequencing (NGS) technique is rapidly expanding and developing; this process establishes a jump by several orders of magnitude in the length of the fragments sequenced and the speed with which this sequencing is carried out. NGS allows a whole human genome to be sequenced in the same amount of time and with the same economic cost required to sequence two or three large genes using the Sanger technique. Use of NGS allows us to go from examining specific genes selected by studying the phenotype to exploring whole genomes of groups of humans or other species. This is making it possible to know not only what an individual genome is like but also how the human genome changes from one person to another, how genomes differ from one group of humans to another, and even how the genome differs in a tumour with respect to the healthy genome of the host (AU)
Assuntos
Humanos , Sequência de Bases , Genoma/genética , Exoma/genética , Técnicas de Genotipagem/métodos , Temas BioéticosRESUMO
La enfermedad de Hirschsprung (HSCR) es un desorden congénito caracterizado por la ausencia de células ganglionares a lo largo del tracto gastrointestinal. Está causada por defectos en la migración de las células del sistema nervioso entérico durante el desarrollo embrionario. La mejora de tratamientos quirúrgicos ha disminuido la mortalidad de los pacientes, lo que facilita el estudio genético de enfermos y sus familiares. Aunque se desconoce la causa genética de la enfermedad, se sospecha que el oncogén RET es el principal involucrado. Se han encontrado alteraciones en este gen en enfermos con HSCR, por lo que algunos autores sugieren que ciertos polimorfismos (SNPs) en el gen podrían causar cierta predisposición genética a padecer esta enfermedad. Nuestro trabajo ha consistido en el análisis del gen RET en pacientes con diagnóstico de HSCR mediante secuenciación directa y genotipado con sondas Taqman®.Los resultados obtenidos indican que ciertos alelos de los polimorfismos p.Leu769Leu (c.2307T>G, Exón 13) p.Gly691Ser (c.2071G>A, Exón 11) y p.Ser904Ser (c.2712C>G, Exón 15) están asociados a losenfermos HSCR, ya que existen diferencias significativas respecto ala población sana (AU)
Hirschsprungs disease (HSCR) is a developmental disorder characterized by the absence of the enteric ganglia along the intestine. Is regarded as the consequence of the premature arrest of the migration of neural crest cells in the hindgut during the embryonic development to form the enteric nervous system (ENS). Is considered, therefore, a neurocristopathy. The development of surgical approaches has importantly decreased mortality and morbility of Hirschsprungs patients, which has allowed the emergence of genetic studies of patients and their families. Although the genetic cause of the disease is still unknown, the RET oncogene is the main involved. Alterations in this gene have been found in HSCR patients, so many authors suggest that certain polymorphisms(SNPs) in this gene could be responsible of genetic predisposition to have the disease. Our work has consisted in the genetic analysis of the RET gene in HSCR patients using direct sequencing and genotyping with Taq-Man® probes. Our results show that some alleles of the polymorphismsp.Leu769Leu (c.2307T>G, Exon 13) p.Gly691Ser (c.2071G>A, Exon11) and p.Ser904Ser (c.2712C>G, Exon 15) are associated to the disease since there are significant differences from the healthy population (AU)
Assuntos
Humanos , Masculino , Feminino , Lactente , Polimorfismo Genético , Doença de Hirschsprung/genética , Proteínas Proto-Oncogênicas c-ret/genética , Sequência de Bases/genética , Éxons/genética , Técnicas de GenotipagemRESUMO
Basándose en el análisis de las secuencias de regiones parciales de los genes Beta-tubulina y ARN ribosómicosse estudió la filogenia, la taxonomía y las interrelaciones de importantes géneros de hongos entomopatógenosasexuales. Se estudio también la estructura de las especis Beauveria bassiana y Nomuraea rileyi. Seanalizó un total de 174 entradas fúngicas que representaban 94 especies. El análisis filogenético demostróque todas las especies de hongos entomopatogénicos asexuales incluidas en el estudio pertenecían a la familiaClavicipitaceae, del orden Hypocreales de los Ascomycota. Se observaron diferentes linajes dentro deB. bassiana, lo que demostró la complejidad de dicha especie. Algunos de los aislamientos de dicha especiedemostraron estar filogenéticamente más separados que determinados géneros morfológicos. Dentro de laespecie N. rileyi se pudo observar también la presencia de especiación críptica. Se concluye que los hongosasexuales entomopatogénicos han evolucionado de un linaje simple dentro de la familia Clavicipitaceae(AU)
The phylogenetic lineage, taxonomic affiliation and interrelationships of important asexualentomopathogenic fungal genera were studied using the sequences of partial regions of Beta-tubulin andrRNA genes. The species structures of Beauveria bassiana and Nomuraea rileyi were also investigated. Atotal of 147 fungal entries covering 94 species were analysed. Phylogenetic analysis placed all the asexualentomopathogenic fungal species analysed, in the family Clavicipitaceae of the order Hypocreales ofAscomycota. Deep phylogenetic lineages were observed in B. bassiana iterating the complex nature of thisspecies. Some of the isolates assigned to this species separated out more distinctly than morphologicallydistinguishable genera. Cryptic speciation was also evident in N. rileyi. It is concluded that the asexualfungi with entomopathogenic habit arose from a single lineage in sexual Clavicipitaceae(AU)
Assuntos
Fungos/genética , Beauveria/genética , Filogenia , Análise de Sequência , Tubulinos/microbiologia , Hypocreales/genética , Fungos Mitospóricos/genética , Sequência de BasesRESUMO
Introducción: se considera éxito terapéutico cuando un paciente con el virus de la inmunodeficiencia humana (VIH) sometido a tratamiento antirretroviral de gran actividad (TARGA) consigue una carga viral plasmática<50copias/ml. Sin embargo, es frecuente encontrar a pacientes cuya carga viral se sitúa en 501.000copias/ml, en estos casos las guías de tratamiento no recomiendan realizar un test genotípico de resistencias aduciendo una baja rentabilidad. El objetivo principal de este estudio fue examinar la utilidad de una técnica de concentración para la secuenciación de VIH-1 desde muestras que contienen menos de 1.000copias/ml, y a partir de aquí determinar las consecuencias virológicas de los cambios guiados por el test de resistencia genotípica del TARGA de estos pacientes. Métodos: se estudió a 51 pacientes con cargas virales de 501.000copias/ml, de los que 27 presentaron estos valores de carga viral durante al menos 12 meses consecutivos. Antes de la extracción del ARN, se concentró una muestra de 3ml de plasma y, a continuación, se genotipó siguiendo el procedimiento estándar. Resultados: se pudo secuenciar 47 muestras de las 51, con una sensibilidad del 92%. De estos 47 pacientes, 27 mantienen carga viral de 501.000copias/ml durante 12 meses, de ellos, 20 consiguen carga viral indetectable al cambiar el TARGA guiado por el genotipo (análisis por intención de tratar; no consta=fracaso; 20 de 27 [74,1%]) (análisis en tratamiento; 20 de 23 [86,9%]).Conclusiones: mostramos una modificación sencilla de la secuenciación genotípica en pacientes con grados de viremia persistentemente bajos, que resulta en una modificación en el régimen del TARGA que consigue una viremia plasmática indetectable (AU)
Introduction: Highly active antiretroviral therapy (HAART) in HIV patients is considered successful when plasma viral load (VL) reaches<50copies/ml. However, many patients have a persistent VL of 50 to 1000copies/ml, and treatment guidelines do not recommend genotypic resistance testing at these levels because of poor performance. The aim of this study was to evaluate the usefulness of a concentration technique for HIV-1 sequencing in samples with<1000copies/ml, and determine the virological consequences of HAART treatment changes guided by resistance testing in this scenario. Methods: Observational study performed in 51 patients with plasma VL between 50 and 1000copies/m; 27 patients had these levels for at least 12 consecutive months. Prior to RNA extraction, virions were concentrated from 3-ml plasma samples and then genotyped following standard procedures. Results: Forty-seven of the 51 samples were successfully sequenced, resulting in a sensitivity of 92%. Among these 47 patients, 27 showed a persistent viral load of 501000copies/ml for 12 months, and 20 patients achieved undetectable viral load following the genotype-guided HAART change (intention-to-treat analysis: NC=F; 20 of 27 [74.1%]; on-treatment analysis: 20 of 23 [86.9%]).Conclusions: We report a simple method for genotype sequencing in patients with persistent low-level viremia that allowed a modification of the HAART regimen leading to undetectable plasma viremia (au)
Assuntos
Humanos , HIV-1/genética , Síndrome de Imunodeficiência Adquirida/genética , Viremia/genética , Síndrome de Imunodeficiência Adquirida/tratamento farmacológico , Sequência de Bases , HIV-1/sangueRESUMO
Most of the somatic epidermal growth factor receptor (EGFR) mutations described to date in non-smallcell lung cancer (NSCLC) patients are located in the kinase domain and are considered activating mutations. Some of these mutations are associated with response to specific EGFR tyrosine kinase inhibitors (TKI) such as gefitinib and erlotinib. Here we report a case of a previously undescribed EGFR nonsense mutation in a lung adenocarcinoma patient who did not derive any clinical benefit with combination chemotherapy and erlotinib. To the best of our knowledge this is the second report in the literature describing an EGFR nonsense mutation in lung cancer patients (AU)
No disponible
Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Quinazolinas/uso terapêutico , Receptores ErbB/genética , /uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Sequência de Bases , Códon sem Sentido , Imuno-Histoquímica/métodos , Imuno-Histoquímica , Hibridização in Situ FluorescenteRESUMO
Objetivo: Conocer los serotipos de adenovirus en pacientes mexicanos con conjuntivitis folicular y queratoconjuntivitis. Métodos: Se analizaron por PCR específica para adenovirus, muestras de fondo de saco conjuntival inferior de 77 pacientes diagnosticados con conjuntivitis folicular por sospecha clínica de infección por adenovirus, de enero de 2005 a diciembre de 2006. La identificación de los serotipos se realizó por secuenciación automatizada. Las secuencias de nucleótidos obtenidos fueron comparados con las secuencias reportadas en el GenBank. En el análisis de los resultados se utilizó la estadística descriptiva. Resultados: Se analizaron 77 muestras de las cuales el 56% presentaron adenovirus. La secuenciación de cada muestra positiva permitió la identificación de Ad1, Ad2, Ad3 y Ad8; las secuencias de los serotipos fueron idénticas a las reportadas en el GenBank con las direcciones: AF 534906 y AY 224420 para una secuencia del gen que codifica el filamento de Ad1 y Ad2 respectivamente y AY 854180 y DQ 149614 para una secuencia del gen que codifica la proteína Hexón de Ad3 y Ad8 respectivamente. En el análisis estadístico, se pudo observar que no existe, en apariencia, una estacionalidad preferencial de los serotipos identificados. Conclusiones: En este trabajo se identificaron los serotipos Ad1, Ad2 y Ad3 en pacientes con diagnóstico clínico de conjuntivitis folicular en el 2005, Ad2 fue el serotipo predominante. También se detectó en un brote de queratoconjuntivitis epidémica por Ad8. Desde el punto de vista epidemiológico, ningún serotipo encontrado parece tener estacionalidad preferente
Objetive: To determine the adenovirus serotype in Mexican patients with folicular conjunctivitis and keratoconjunctivitis. Methods: Adenovirus-specific PCR was used to analyze sample scrapings from the inferior fornix of patients with follicular conjunctivitis and clinical suspicion of adenovirus from January 2005 to December 2006. Identification of the serotype was made by automated sequencing. The nucleotide sequences obtained were compared with the reported sequences in GenBank. Descriptive statistical analyses were performed on the results. Results: Of the 77 samples with clinical data of follicular conjunctivitis that were analyzed, 43 (56%) presented adenovirus. The sequencing of each positive sample allowed the identification of Ad1, Ad2, Ad3 and Ad8; the sequences of the serotype were identical those reported in GenBank with accession numbers: AF 534906 and AY 224420 for a sequence of the gene coding for the filament of Ad1 and Ad2 respectively, and AY 854180 and DQ 149614 for a sequence of the gene that codes for the Hexon protein of Ad3 and Ad8 respectively. From the statistical analysis it was possible to determine that a preferential seasonality of the serotype does not exist. Conclusion: In this work the Ad1, Ad2 and Ad3 serotypes were identified in patients with clinical diagnosis of follicular conjunctivitis in 2005. Ad2 was the predominant serotype. Ad8 was also detected in an outbreak of epidemic keratoconjunctivitis. From an epidemiological point of view, no serotype found seems to have a preferred seasonality (Arch Soc Esp Oftalmol 2008; 83: 161-168)
Assuntos
Humanos , Conjuntivite Viral/virologia , Ceratoconjuntivite/virologia , Adenovírus Humanos/genética , Adenovírus Humanos/isolamento & purificação , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Sequência de BasesRESUMO
Objetivos. Analizar en tumores cerebrales, fundamentalmente de estirpe neuro-epitelial, la existencia de mutaciones en los cromosomas 1p y 19q por la técnica de análisis de la pérdida de hetero cigocidad (LOH). Un primer objetivo implícito fue poner a punto la técnica del análisis. Método. Hemos investigado la existencia de mutaciones en 3 alelos seleccionados del cromosoma 1p y en 2alelos del 19q de distintos tumores cerebrales de estirpeglial intervenidos de manera consecutiva en nuestro Centro desde Octubre de 2004 a Marzo de 2006. La metodología empleada ha sido la detección en ADN tumoral de tejido en fresco y en sangre del paciente del marcaje por PCR de amplificados y electroforesis analizando la pérdida de heterocigocidad de microsatélites, repeticiones de dinucleótidos, situados en D1S508, D1S2734, D1S199, D19S412 y D19S219. Resultados. Hemos incluido en esta primera fase de estudio un total de 45 muestras de pacientes intervenidos de tumores cerebrales supratentoriales de estirpe neuroepitelial y que incluyen: 29 glioblastomas, 1 gliosarcoma,7 astrocitomas grado II, 1 oligoastrocitoma, 3 oligodendrogliomas, 1 oligodendroglioma anaplásico,1 xantoastrocitoma, 1 tumor neuroepitelial disembrioplásico y 1 astrocitoma pilocítico. La presencia de mutación la hemos considerado cuando el índicealélico T1/ T2 era inferior a 0.8.Nl/N2 Por estirpe histológica destaca la presencia de mutaciónen un 80% de tumores oligodendrogliales, 14% deglioblastomas y 14% de astrocitomas fibrilares grado II. Conclusiones. La técnica de análisis de LOH en1p/19q es factible de realizar en centros que dispongan de técnicas de estudios genético-moleculares, con un alto índice de fiabilidad. De su resultado se desprende qué pacientes se pueden beneficiar del tratamiento con alquilantes añadiendo, a la terapia quirúrgica y/oradio terápica en uso hasta la fecha, una posibilidad de tratamiento con alto porcentaje de respuestas
Background. To analyze in cerebral tumors of neuroepithelial tissue 1p/19q codeletions by study of loss of heterozygosity (LOH). A first implied objective was to get ready this molecular thecnique. Methods. We aimed to determine several deletion smapping 1p and 19q chromosomes, three allelic loss of1p and two allelic loss of 19q, in patients with cerebral tumors which were operated in our Deparment from October 2004 until March 2006. We have detected in blood and tumoral DNA loss of heterozygosity assay for molecular detection using PCR and capillary array electrophoresis of five markers (D1S508, D1S2734,D1S199, D19S412 y D19S219). Results. Were included in the first part of this study 45sample of neuroepithelial tissue supratentorial tumors:29 glioblastoma, 1 gliosarcoma, 7 diffuse astrocytomagrade II, 1 oligoastrocytoma, 3 oligodendroglioma, 1anaplastic oligodendroglioma, 1 xanthoastrocytoma, 1dysembryoplastic neuroepithelial tumour and 1 pilocyticastrocytoma. We considered deleted regions identified when allelic ratio T1/T2 was lower than 0.8. 80% of oligodendroglial tumors, 14% glioblastoma and14% of diffuse astrocytoma grade II. Conclusions. Evaluation of 1p/19q allelic status by LOH analysis may provide useful information for guiding clinical and therapeutical decisions with high succes ratio. These results shown why patients with1p/19q codeletion survive longer, because adjuvant alkylants adds further improvements to standard, surgery and radiotherapy, treatments
Assuntos
Humanos , Neoplasias Encefálicas/genética , Cromossomos Humanos Par 1 , Cromossomos Humanos Par 19 , Perda de Heterozigosidade , Neoplasias Neuroepiteliomatosas/genética , Mutação , Estudos Retrospectivos , Repetições de Microssatélites , Dados de Sequência Molecular , DNA de Neoplasias/análise , Marcadores Genéticos , Sequência de BasesRESUMO
Molecular studies of many types of cancer have revealed that clinically evident tumours carry multiple genetic and epigenetic abnormalities, including DNA sequence alterations, chromosome copy number changes and aberrant promoter hypermethylation. Together, these aberrant changes result in the activation of oncogenes and inactivation of tumour-suppressor genes (TSG). In many cases these abnormalities can be found in premalignant lesions and even in histological normal adjacent cells. Many tumour types are difficult to detect early and are frequently resistant to available chemotherapy and radiotherapy. Therefore, the early detection, chemoprevention and the design of new therapeutic strategies based on the increased understanding of cancer molecular changes are one of the great challenges nowadays. Insertions of a methyl group at the fifth carbon of cytosines within the dinucleotide 5'- CpG-3' is the best studied epigenetic mechanism. DNA methylation acts together with others mechanisms like histone modification, chromatin remodelling and microRNAs to mould the DNA structure according to the functional state required. The aberrant methylation of the CpG islands located at the promoter region of specific genes is a common and early event involved in cancer development. Thus, hypermethylated DNA sequences from tumours are one of the most promising markers for early detection screenings as well as tumour classification and chemotherapy response in many types of cancer (AU)
Assuntos
Humanos , Masculino , Feminino , Biomarcadores/análise , Biomarcadores/metabolismo , Metilação de DNA , Modelos Biológicos , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Supressão Genética , Sequência de Bases , Ilhas de CpG/fisiologia , DNA/metabolismo , Dados de Sequência Molecular , Neoplasias/classificaçãoRESUMO
El síndrome de Hutchinson-Gilford es un síndrome progeroide que se caracteriza por un envejecimiento acelerado que comienza tempranamente en la infancia. El estudio de células de pacientes y el desarrollo de modelos animales (Zmpste24/, Zmpste24/Lmna+/, LmnaLCO/LCO) que reproducen esta dolencia ha aportado nuevos conocimientos para entender las bases genéticas de esta enfermedad y así también profundizar en las del envejecimiento fisiológico. El fenotipo característico de este síndrome se debe a alteraciones en la lamina nuclear, estructura formada por un conjunto de filamentos intermedios (laminas A, B y C) que permiten mantener la organización de la envoltura nuclear. Se ha demostrado que una mutación del gen LMNA, que sintetiza la lamina A, es la del depósito de lamina A farnesilada (progerina) que es la causante de las alteraciones en la envoltura nuclear y del fenotipo de este raro síndrome. El empleo de moléculas que actúan sobre diferentes pasos en la síntesis de progerina se está revelando como un futuro terapéutico prometedor para revertir los efectos nocivos de su síntesis
Hutchinson-Gilford disease is a progeroid syndrome characterized by accelerated ageing beginning in early childhood. Study of several types of cells from patients with this syndrome and the development of animal models (Zmpste24/, Zmpste24/Lmna+/, LmnaLCO/LCO) that mimic this disease have increased knowledge of the genetic foundations of this rare entity and those of normal ageing. The phenotypic features of this syndrome are caused by alterations in the fibrillar components of the nuclear lamina (lamins A, B, and C), which maintain the structure of the nuclear envelope. A point mutation in the gene for lamin A (LMNA) induces deposit of a farnesylated lamin A (progerin), which causes the nuclear alterations observed in the affected cells. The use of several molecules that interfere with progerin synthesis has been proposed as a promising potential therapeutic approach to reverse the adverse effects of progerin synthesis
Assuntos
Animais , Humanos , Senilidade Prematura/genética , Lamina Tipo A/genética , Mutação/genética , Sítios de Splice de RNA/genética , Splicing de RNA/genética , Análise Mutacional de DNA , Processamento Alternativo/genética , RNA Mensageiro/genética , Sequência de Bases , Síndrome , AlelosRESUMO
Alterations in the erm(A) regulatory region of six clinical isolates of Staphylococcus epidermidis and one of Staphylococcus haemolyticus displaying a constitutive resistance phenotype were investigated. A novel deletion of 10 bp with respect to the corresponding sequence of Tn554 was identified in the attenuator of a constitutively expressed erm(A) gene of one of the S. epidermidis isolates. Thus far, this is the smallest deletion conferring constitutive resistance in the translational attenuator of erm(A) in a naturally occurring S. epidermidis strain of human origin (AU)
No disponible
Assuntos
Staphylococcus epidermidis/genética , Antibacterianos/farmacologia , Metiltransferases/genética , Macrolídeos/farmacologia , Proteínas de Bactérias/genética , Staphylococcus epidermidis/isolamento & purificação , Staphylococcus epidermidis/patogenicidade , Deleção Cromossômica , Elementos de DNA Transponíveis/genética , Sequência de BasesRESUMO
Introduction: Kearns-Sayre syndrome (KSS) is a mitochondrial disorder characterized by progressive external ophthalmoplegia, pigmentary retinopathy, onset before 20 years, and ragged-red fibers on muscle biopsy. KSS has been associated to mitochondrial DNA (mtDNA) mutations. We report neurological manifestations and mtDNA deletions in KSS. Methods: Six KSS patients underwent neurological examination, biochemical analysis (muscle enzymes, lactate, cerebrospinal fluid analysis), electromicrography, muscle biopsy (Gomori stain, electronic microscopy), electrocardiogram, echocardiography, MRI/CT scan. MtDNA deletions were studied in blood and muscle samples using Southern blotting and long polymerase chain reaction. Results: Four males and two females (mean age: 27.7 years; range: 17-42; mean age at onset: 8.2 years) were studied. Initial symptoms were ptosis and gaze restriction, fatigue, exercise intolerance and proximal limb weakness. Syncope and neurosensory hypoacusia were initial symptoms in two patients. All of them presented a unique deletion in the mitochondrial genome, in heteroplasmy, and their size was in the range of 4,420 and 9,437 basis pairs. Three of these deletions are reported for the first time in this article. Most of the deletions are flanked by small direct repeats elements. Conclusions: Proximal muscle weakness and fatigue appear frequently in KSS patients during follow up. The syndrome in these patients has been caused by mtDNA deletions (AU)
Introducción. El síndrome de Kearns-Sayre (SKS) es un fenotipo mitocondrial caracterizado por oftalmoplejía externa progresiva, retinitis pigmentaria, inicio antes de los 20 años y fibras rojo rasgadas en la biopsia muscular y que ha sido asociado a mutaciones en el ADN mitocondrial (ADNmt). Métodos. Se realizaron exámenes neurológicos en seis pacientes con SKS, determinación de enzimas musculares y de lactato en sangre, análisis de líquido cefalorraquídeo (LCR), electromiografía, biopsia muscular, electrocardiograma, ecocardiograma y estudios de neuroimagen. Asimismo se llevó a cabo un análisis genético moleculares del ADNmt en muestras de sangre y músculo, por técnicas de hibridación Southern y amplificación por reacción en cadena de la polimerasa larga para estudiar la presencia de posibles deleciones. Encontramos manifestaciones neurológicas y deleciones en el ADNmt en el SKS. Resultados. Se han estudiado cuatro varones y dos mujeres (edad media: 27,7 años; rango: 17-42) con una edad media de inicio de los síntomas a los 8,2 años. La clínica inicial fue ptosis palpebral, seguida de limitación progresiva de la mirada vertical y horizontal, fatiga e intolerancia al ejercicio y debilidad de músculos proximales. En dos pacientes los síntomas iniciales fueron síncopes de repetición y sordera neurosensorial. Todos los pacientes presentaban una deleción única en el ADNmt, en heteroplasmia y con un tamaño que variaba entre 4.420 y 9.437 pares de bases. Tres de estas deleciones se describen por primera vez. La mayoría presenta secuencias de repetición directa en las zonas que flanquean la deleción. Conclusiones. El SKS evoluciona en el tiempo con debilidad muscular proximal y fatiga. Todos están causados por deleciones del ADNmt (AU)
