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INTRODUCTION: The placenta provides nutrients to the fetus, and it has protective effects against harmful substances. Unhealthy maternal diets and toxic agents might increase free radical (FR) production. Elevated FR levels are associated with a high risk of oxidative stress, which may cause DNA damage. DNA might be oxidized in the placenta, occasionally affecting its methylation profile due to 8-hidroxy-2'-deoxyguanosine formation. METHODS: This study assessed 130 mothers and their children. The maternal's nutritional patterns were determined using the Food Frequency Questionnaire. Information on smoking and alcohol consumption was collected during the medical examination. Data on placental DNA were obtained to determine the MTHFR 677C/T genotype and the proportion of placental DNA methylation (pDNAm). RESULTS: Consumption of vitamins and folic acid was above 85%. The pDNAm was found to be correlated with gestational age and coffee intake. Mothers with a smoking history had a low pDNAm. Placentas with the TT genotype had a higher but not significant pDNAm. In the placentas with the CC/CT genotype, the pDNAm was positively associated with carbohydrate and biotin intake. However, the TT genotype was negatively associated with folate and vegetable intake. DISCUSSION: The pDNAm was positively associated with coffee intake, but not with macro-, and micronutrient intake. However, it was negatively associated with cigarette smoking. The placentas with the CC/CT genotype had a lower pDNAm than those with the TT genotype. In the placentas with the CC/CT or TT genotype, methylation was positively, and negatively associated with micro- or macronutrients, respectively.
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Metilación de ADN , Placenta , Niño , Humanos , Femenino , Embarazo , Café , Dieta , Genotipo , Ácido Fólico , ADN , Fumar/efectos adversos , Metilenotetrahidrofolato Reductasa (NADPH2)/genéticaRESUMEN
BACKGROUND: Opitz GBBB syndrome (GBBB) is an X-linked disease characterized by midline defects, including congenital heart defects. We present our diagnostic approach to the identification of GBBB in a consanguineous family in which two males siblings were concordant for a total anomalous connection of pulmonary veins and minor facial dysmorphias. METHODS: Targeted exome sequencing analysis of a 380-gene panel associated with cardiovascular disease was performed on the propositus. Interpretative analysis of the exome results was conducted, and 3D models of the protein changes were generated. RESULTS: We identified a NM_000381.4:c.608G>A;p.(Arg203Gln) change in MID1, affecting the conformation of the B-box 2 domain of the protein, with a zinc finger structure and associated protein interactions. This clinical phenotype is consistent with GBBB; however, the type of congenital heart disease observed in this case has not been previously reported. CONCLUSION: A new likely pathogenic variant on MID1 c.608G>A was found to be associated with Opitz GBBB syndrome.
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Enfermedades Genéticas Ligadas al Cromosoma X , Hipertelorismo , Hipospadias , Humanos , Masculino , Enfermedades Genéticas Ligadas al Cromosoma X/genética , Hipertelorismo/genética , Hipospadias/genéticaRESUMEN
During pregnancy, appropriate nutritional support is necessary for the development of the foetus. Maternal nutrition might protect the foetus from toxic agents such as free radicals due to its antioxidant content. In this study, 90 mothers and their children were recruited. DNA damage mediated by oxidative stress (OS) was determined by the levels of 8-hidroxy-2'-deoxyguanosine (8-OHdG) in the plasma of women and umbilical cord blood. The mothers and newborns were categorised into tertiles according to their 8-OHdG levels for further comparison. No relevant clinical differences were observed in each group. A strong correlation was observed in the mother−newborn binomial for 8-OHdG levels (Rho = 0.694, p < 0.001). In the binomial, a lower level of 8-OHdG was associated with higher consumption of calories, carbohydrates, lipids, and vitamin A (p < 0.05). In addition, the levels of 8-OHdG were only significantly lower in newborns from mothers with a higher consumption of vitamin A and E (p < 0.01). These findings were confirmed by a significant negative correlation between the 8-OHdG levels of newborns and the maternal consumption of vitamins A and E, but not C (Rho = −0.445 (p < 0.001), −0.281 (p = 0.007), and −0.120 (p = 0.257), respectively). Multiple regression analysis showed that the 8-OHdG levels in mothers and newborns inversely correlated with vitamin A (ß = −1.26 (p = 0.016) and −2.17 (p < 0.001), respectively) and pregestational body mass index (ß = −1.04 (p = 0.007) and −0.977 (p = 0.008), respectively). In conclusion, maternal consumption of vitamins A and E, but not C, might protect newborns from DNA damage mediated by OS.
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Overweight and obesity have become a world-health public problem, mainly for developing countries. Both health conditions have a higher prevalence among women of childbearing age. Physiopathology, overweight and obesity are characterized by a chronic oxidative stress status, which has deleterious effects on mothers and children. Hence, we determine whether the qualities of diet during pregnancy and maternal pregestational body mass index (BMI) are associated with increased oxidative stress markers in mothers and newborns. Two hundred forty-two (242) mother-newborn pairs were classified according to their pregestational BMI. Information on food intake was collected using a food frequency questionnaire in the third trimester of pregnancy. Levels of Malondialdehyde (MDA) and Nitric Oxide (NO) were measured in plasma from mothers at the end of the third trimester of pregnancy and from cord blood at birth. MDA and NO levels in mother-newborn pairs with maternal pregestational overweight or obesity were higher than in mother-newborn pairs with pregestational normal weight. For women (and newborns) who had a higher intake of fruit and vegetables, the levels of NO and MDA were lower. Lastly, women with pregestational obesity had lower fruit and vegetable intake during pregnancy and higher levels of oxidative stress and in their newborns.
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Obesidad Materna , Índice de Masa Corporal , Niño , Estudios Transversales , Dieta/efectos adversos , Femenino , Humanos , Recién Nacido , Estrés Oxidativo , EmbarazoRESUMEN
Currently, there are over 230 different COVID-19 vaccines under development around the world. At least three decades of scientific development in RNA biology, immunology, structural biology, genetic engineering, chemical modification, and nanoparticle technologies allowed the accelerated development of fully synthetic messenger RNA (mRNA)-based vaccines within less than a year since the first report of a SARS-CoV-2 infection. mRNA-based vaccines have been shown to elicit broadly protective immune responses, with the added advantage of being amenable to rapid and flexible manufacturing processes. This review recapitulates current advances in engineering the first two SARS-CoV-2-spike-encoding nucleoside-modified mRNA vaccines, highlighting the strategies followed to potentiate their effectiveness and safety, thus facilitating an agile response to the current COVID-19 pandemic.
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Ingeniería Biomédica , Vacunas contra la COVID-19 , COVID-19 , Desarrollo de Medicamentos/métodos , Descubrimiento de Drogas/métodos , SARS-CoV-2 , Vacuna nCoV-2019 mRNA-1273 , Ingeniería Biomédica/métodos , Ingeniería Biomédica/tendencias , COVID-19/prevención & control , COVID-19/virología , Vacunas contra la COVID-19/clasificación , Vacunas contra la COVID-19/farmacología , Sistemas de Liberación de Medicamentos/métodos , Humanos , Inmunogenicidad Vacunal , Liposomas/farmacología , Nanopartículas , Nucleósidos/farmacología , Nucleósidos/fisiología , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Vacunas Sintéticas/farmacologíaRESUMEN
MicroRNAs (miRNAs) have a prominent role in virtually every aspect of cell biology. Due to the small size of mature miRNAs, the high degree of similarity between miRNA family members, and the low abundance of miRNAs in body fluids, miRNA expression profiling is technically challenging. Biosensors based on electrochemical detection for nucleic acids are a novel category of inexpensive and very sensitive diagnostic tools. On the other hand, after recognizing the target sequence, specific CRISPR-associated proteins, including orthologues of Cas12, Cas13, and Cas14, exhibit collateral nonspecific catalytic activities that can be employed for specific and ultrasensitive nucleic acid detection from clinically relevant samples. Recently, several platforms have been developed, connecting the benefits of enzyme-assisted signal amplification and enzyme-free amplification biosensing technologies with CRISPR-based approaches for miRNA detection. Together, they provide high sensitivity, precision, and fewer limitations in diagnosis through efficient sensors at a low cost and a simple miniaturized readout. This review provides an overview of several CRISPR-based biosensing platforms that have been developed and successfully applied for ultrasensitive and specific miRNA detection.
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Sistemas CRISPR-Cas/genética , MicroARNs/análisis , Animales , Técnicas Biosensibles , Colorimetría , Electroquímica , Ingeniería Genética , Humanos , MicroARNs/genéticaRESUMEN
The genome of the SARS-CoV-2 virus, the causal agent of the COVID-19 pandemic, has diverged due to multiple mutations since its emergence as a human pathogen in December 2019. Some mutations have defined several SARS-CoV-2 clades that seem to behave differently in terms of regional distribution and other biological features. Next-generation sequencing (NGS) approaches are used to classify the sequence variants in viruses from individual human patients. However, the cost and relative scarcity of NGS equipment and expertise in developing countries prevent studies aimed to associate specific clades and variants to clinical features and outcomes in such territories. As of March 2021, the GR clade and its derivatives, including the B.1.1.7 and B.1.1.28 variants, predominate worldwide. We implemented the post-PCR small-amplicon high-resolution melting analysis to genotype SARS-CoV-2 viruses isolated from the saliva of individual patients. This procedure was able to clearly distinguish two groups of samples of SARS-CoV-2-positive samples predicted, according to their melting profiles, to contain GR and non-GR viruses. This grouping of the samples was validated by means of amplification-refractory mutation system (ARMS) assay as well as Sanger sequencing.
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COVID-19/virología , Técnicas de Genotipaje/métodos , SARS-CoV-2/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Mutación , Desnaturalización de Ácido Nucleico , ARN Viral/aislamiento & purificaciónRESUMEN
Background: Severe coronavirus disease 2019 (COVID-19) is infrequent in children and shows a mortality rate of around 0.08%. This study aims to explore international differences in the pediatric mortality rate. Methods: We analyzed several countries with populations over 5 million that report disaggregated data of COVID-19 deaths by quinquennial or decennial age groups. Data were extracted from COVID-19 cases and deaths by age database, National Ministeries of Health, and the World Health Organization. Results: We included 23 countries in the analysis. Pediatric mortality varied from 0 to 12.1 deaths per million children of the corresponding age group, with the highest rate in Peru. In most countries, deaths were more frequent in the 0-4-year-old age group, except for Brazil. The pediatric/general COVID-19 mortality showed a great variation and ranged from 0% (Republic of Korea) to 10.4% (India). Pediatric and pediatric/general COVID mortality correlates strongly with 2018 neonatal mortality (r = 0.77, p < 0.001; and r = 0.88, p < 0.001, respectively), while shows a moderate or no correlation (r = 0.47, p = 0.02; and r = 0.19, p = 0.38, respectively) with COVID-19 mortality in the general population. Conclusions: International heterogeneity in pediatric COVID-19 mortality importantly parallels historical neonatal mortality. Neonatal mortality is a well-known index of the quality of a country's health system, which points to the importance of social determinants of health in pediatric COVID-19 mortality disparities. This issue should be further explored.
Introducción: La COVID-19 grave es poco frecuente en la infancia. El objetivo de este estudio fue explorar las diferencias en la tasa de mortalidad internacional por COVID-19 en la población pediátrica. Método: Se analizaron países con poblaciones superiores a 5 millones de habitantes que reporten muertes por COVID-19 con datos desglosados por grupos de edad quinquenales o decenales. Los datos se extrajeron de la base de datos COVerAge-DBs, de los ministerios nacionales de salud y de la Organización Mundial de la Salud. Resultados: Se incluyeron 23 países. La mortalidad pediátrica varió de 0 a 12.1 muertes por millón de personas del grupo de edad correspondiente, con la tasa más alta en Perú. En la mayoría de los países, las muertes fueron más frecuentes en el grupo de 0 a 4 años, excepto en Brasil. La mortalidad pediátrica/general por COVID-19 mostró una gran variación entre países y osciló entre el 0% (República de Corea) y el 10.4% (India). La mortalidad pediátrica y pediátrica/general por COVID-19 se correlaciona fuertemente con la mortalidad neonatal de 2018, mientras que tiene una moderada o nula correlación con la mortalidad por COVID-19 en la población general. Conclusiones: Existe una importante heterogeneidad internacional en la mortalidad pediátrica por COVID-19, que es paralela a la mortalidad neonatal histórica, la cual es un indicador de la calidad de los sistemas de salud y señala la importancia de los determinantes sociales de la salud en las disparidades de mortalidad pediátrica por COVID-19. Este tema debe explorarse a fondo.
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COVID-19/mortalidad , Pandemias , SARS-CoV-2 , Adolescente , Distribución por Edad , Niño , Preescolar , Salud Global , Humanos , Lactante , Recién NacidoRESUMEN
Abstract Background: Severe coronavirus disease 2019 (COVID-19) is infrequent in children and shows a mortality rate of around 0.08%. This study aims to explore international differences in the pediatric mortality rate. Methods: We analyzed several countries with populations over 5 million that report disaggregated data of COVID-19 deaths by quinquennial or decennial age groups. Data were extracted from COVID-19 cases and deaths by age database, National Ministeries of Health, and the World Health Organization. Results: We included 23 countries in the analysis. Pediatric mortality varied from 0 to 12.1 deaths per million children of the corresponding age group, with the highest rate in Peru. In most countries, deaths were more frequent in the 0-4-year-old age group, except for Brazil. The pediatric/general COVID-19 mortality showed a great variation and ranged from 0% (Republic of Korea) to 10.4% (India). Pediatric and pediatric/general COVID mortality correlates strongly with 2018 neonatal mortality (r = 0.77, p < 0.001; and r = 0.88, p < 0.001, respectively), while shows a moderate or no correlation (r = 0.47, p = 0.02; and r = 0.19, p = 0.38, respectively) with COVID-19 mortality in the general population. Conclusions: International heterogeneity in pediatric COVID-19 mortality importantly parallels historical neonatal mortality. Neonatal mortality is a well-known index of the quality of a country's health system, which points to the importance of social determinants of health in pediatric COVID-19 mortality disparities. This issue should be further explored.
Resumen Introducción: La COVID-19 grave es poco frecuente en la infancia. El objetivo de este estudio fue explorar las diferencias en la tasa de mortalidad internacional por COVID-19 en la población pediátrica. Método: Se analizaron países con poblaciones superiores a 5 millones de habitantes que reporten muertes por COVID-19 con datos desglosados por grupos de edad quinquenales o decenales. Los datos se extrajeron de la base de datos COVerAge-DBs, de los ministerios nacionales de salud y de la Organización Mundial de la Salud. Resultados: Se incluyeron 23 países. La mortalidad pediátrica varió de 0 a 12.1 muertes por millón de personas del grupo de edad correspondiente, con la tasa más alta en Perú. En la mayoría de los países, las muertes fueron más frecuentes en el grupo de 0 a 4 años, excepto en Brasil. La mortalidad pediátrica/general por COVID-19 mostró una gran variación entre países y osciló entre el 0% (República de Corea) y el 10.4% (India). La mortalidad pediátrica y pediátrica/general por COVID-19 se correlaciona fuertemente con la mortalidad neonatal de 2018, mientras que tiene una moderada o nula correlación con la mortalidad por COVID-19 en la población general. Conclusiones: Existe una importante heterogeneidad internacional en la mortalidad pediátrica por COVID-19, que es paralela a la mortalidad neonatal histórica, la cual es un indicador de la calidad de los sistemas de salud y señala la importancia de los determinantes sociales de la salud en las disparidades de mortalidad pediátrica por COVID-19. Este tema debe explorarse a fondo.
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Adolescente , Niño , Preescolar , Humanos , Lactante , Recién Nacido , Pandemias , SARS-CoV-2 , COVID-19/mortalidad , Salud Global , Distribución por EdadRESUMEN
Resumen La revisión por pares tradicional atraviesa por crecientes cuestionamientos, dado el aumento en el fraude científico detectado y la crisis de replicación que recientemente se ha presentado en la investigación biomédica. Investigadores, instituciones académicas y agencias de financiamiento activamente promueven el análisis del registro científico y se han desarrollado múltiples herramientas para lograrlo. Diferentes revistas biomédicas se fundaron con la revisión por pares pospublicación como característica; existen varias plataformas digitales que hacen posible este proceso. Asimismo, cada vez hay más revistas biomédicas que permiten comentar artículos publicados en sus sitios web, lo cual también es posible en repositorios de preimpresiones. Sumado a esto, las casas editoriales y los investigadores están usando ampliamente las redes sociales para la difusión y discusión de artículos, lo cual a veces culmina en refutaciones y retracciones.
Abstract Traditional peer review is undergoing increasing questioning, given the increase in scientific fraud detected and the replication crisis biomedical research is currently going through. Researchers, academic institutions, and research funding agencies actively promote scientific record analysis, and multiple tools have been developed to achieve this. Different biomedical journals were founded with post-publication peer review as a feature, and there are several digital platforms that make this process possible. In addition, an increasing number biomedical journals allow commenting on articles published on their websites, which is also possible in preprint repositories. Moreover, publishing houses and researchers are largely using social networks for the dissemination and discussion of articles, which sometimes culminates in refutations and retractions.
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Humanos , Edición/normas , Revisión de la Investigación por Pares/métodos , Control de Calidad , Factores de Tiempo , Mala Conducta Científica/estadística & datos numéricosRESUMEN
BACKGROUND: Focal dermal hypoplasia (FDH) is rare X-linked dominant disease characterized by atrophy and linear pigmentation of the skin, split hand/foot deformities and ocular anomalies. FDH is caused by mutations of the Porcupine (PORCN) gene, which encodes an enzyme that catalyzes the palmitoylation of Wnt ligands required for their secretion. High resolution melting analysis (HRM) is a technique that allows rapid, labor-efficient, low-cost detection of genomic variants. In the present study, we report the successful implementation of HRM in the molecular diagnosis of FDH. METHODS: Polymerase chain reaction and HRM assays were designed and optimized for each of the coding exons of the PORCN gene, processing genomic DNA samples form a non-affected control and a patient complying with the FDH diagnostic criteria. The causal mutation was characterized by Sanger sequencing from an amplicon showing a HRM trace suggesting heterozygous variation and was validated using an amplification-refractory mutation system (ARMS) assay. RESULTS: The melting profiles suggested the presence of a variant in the patient within exon 1. Sanger sequencing revealed a previously unknown C to T transition replacing a glutamine codon for a premature stop codon at position 28, which was validated using ARMS. CONCLUSIONS: Next-generation sequencing facilitates the molecular diagnosis of monogenic disorders; however, its cost-benefit ratio is not optimal when a single, small or medium size causal gene is already identified and the clinical diagnostic presumption is strong. Under those conditions, as it is the case for FDH, HRM represents a cost- and labor-effective approach.
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Aciltransferasas/genética , Exones/genética , Hipoplasia Dérmica Focal/diagnóstico , Hipoplasia Dérmica Focal/genética , Proteínas de la Membrana/genética , Desnaturalización de Ácido Nucleico/genética , Secuencia de Aminoácidos , Codón sin Sentido , Femenino , Hipoplasia Dérmica Focal/fisiopatología , Heterocigoto , Humanos , Lactante , Mutación , Filogenia , Reacción en Cadena de la Polimerasa/métodos , Alineación de SecuenciaRESUMEN
Traditional peer review is undergoing increasing questioning, given the increase in scientific fraud detected and the replication crisis biomedical research is currently going through. Researchers, academic institutions, and research funding agencies actively promote scientific record analysis, and multiple tools have been developed to achieve this. Different biomedical journals were founded with post-publication peer review as a feature, and there are several digital platforms that make this process possible. In addition, an increasing number biomedical journals allow commenting on articles published on their websites, which is also possible in preprint repositories. Moreover, publishing houses and researchers are largely using social networks for the dissemination and discussion of articles, which sometimes culminates in refutations and retractions.La revisión por pares tradicional atraviesa por crecientes cuestionamientos, dado el aumento en el fraude científico detectado y la crisis de replicación que recientemente se ha presentado en la investigación biomédica. Investigadores, instituciones académicas y agencias de financiamiento activamente promueven el análisis del registro científico y se han desarrollado múltiples herramientas para lograrlo. Diferentes revistas biomédicas se fundaron con la revisión por pares pospublicación como característica; existen varias plataformas digitales que hacen posible este proceso. Asimismo, cada vez hay más revistas biomédicas que permiten comentar artículos publicados en sus sitios web, lo cual también es posible en repositorios de preimpresiones. Sumado a esto, las casas editoriales y los investigadores están usando ampliamente las redes sociales para la difusión y discusión de artículos, lo cual a veces culmina en refutaciones y retracciones.
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Revisión de la Investigación por Pares/métodos , Edición/normas , Humanos , Control de Calidad , Mala Conducta Científica/estadística & datos numéricos , Factores de TiempoRESUMEN
BACKGROUND: 22q11.2 deletion syndrome is a medical condition that results from genomic loss at chromosome 22. Affected patients exhibit large variability that ranges from a severe condition to mild symptoms. In addition, the spectrum of clinical features differs among populations and even within family members. The facial features related to this syndrome are not an exception, and although part of its variation arises through development, few studies address this topic in order to understand the intra and inter-population heterogeneities. Here, we analyze the ontogenetic dynamics of facial morphology of Mexican patients with del22q11.2 syndrome. METHODS: Frontal facial photographs of 37 patients (mean age = 7.65 ± 4.21 SE) with del22q11.2DS and 200 control subjects (mean age = 7.69 ± 4.26 SE) were analyzed using geometric morphometric methods. Overall mean shape and size differences between patients and controls were analyzed, as well as differences in ontogenetic trajectories (i.e. development, growth, and allometry). RESULTS: We found that Mexican patients show typical traits that have been reported for the Caucasian population. Additionally, there were significant differences between groups in the facial shape and size when all the ontogenetic stages were considered together and, along ontogeny. The developmental and allometric trajectories of patients and controls were similar, but they differed in allometric scaling. Finally, patients and controls showed different growth trajectories. CONCLUSION: The results suggest that the typical face of patients with del22q11.2DS is established prenatally; nonetheless, the postnatal ontogeny could influence the dysmorphology and its variability through size-related changes.
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Craneosinostosis , Síndrome de DiGeorge , Cara , Síndrome de Marfan , Variación Biológica Poblacional , Niño , Preescolar , Síndrome de DiGeorge/complicaciones , Cara/anomalías , Humanos , FenotipoRESUMEN
BACKGROUND: MicroRNAs (miRNAs) modulate gene expression through destabilization or translational inhibition of cytoplasmic transcripts or by transcriptional regulation through binding to genomic DNA. Although miRNAs are globally down-regulated in cancer, some are overexpressed in neoplastic tissues, playing key roles in tumorigenesis (oncomiRs), sometimes behaving as effective cancer markers. METHODS: Using total RNA from human uterus adenocarcinoma and non-neoplastic uterus, we conducted a small RNA-sequencing experiment followed by prediction of novel miRNAs using MirDeep* software. Synteny analysis and whole genome alignments were performed using BLAST. We also evaluated expression by a reverse transcriptase-polymerase chain reaction (RT-PCR) in normal tissues of the FSD2 gene, which spans the human miR-1839-5p gene in the opposite direction. RESULTS: MirDeep* analysis predicted a miRNA not previously annotated in databases, identical to and likely the orthologue of mouse miR-1839-5p. Whole-genome local alignments of this miRNA revealed a single perfect hit that is indeed syntenic to mouse miR-1839-5p. Alignments with other mammalian orthologues showed considerable conservation. We validated the prediction via a stem-loop RT-PCR assay, also employed to screen RNA samples from several additional normal and cancer tissues, showing increased expression in neoplastic tissues compared to their respective non neoplastic counterparts. Human heart tissue expresses both miR-1839-5p and FSD2. CONCLUSIONS: Human tissues express an orthologue of mouse miR-1839-5p and, given its expression pattern, we suggest that this miRNA could be explored as a potential oncomiR or cancer marker. Also, according to the genomic organization of miR-1839-5p and FSD2, perfect complementarity exists between the two elements, making possible miRNA-directed cleavage in human cardiac tissue.
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Biomarcadores de Tumor , MicroARNs , Neoplasias/genética , ARN Interferente Pequeño , Secuencia de Aminoácidos , Animales , Biología Computacional/métodos , Secuencia Conservada , Perfilación de la Expresión Génica , Genoma Humano , Genómica/métodos , Secuenciación de Nucleótidos de Alto Rendimiento , HumanosRESUMEN
BACKGROUND: Hundreds of microRNAs (miRNAs), comprising small non-coding RNAs of 20-24 nucleotides, have been discovered, although the entirety of their biological functions is poorly understood. Overexpression or suppression approaches are commonly performed to investigate the function of specific miRNAs. In the present study, we focused on generating a lentiviral vector-based strategy that enables hsa-miR-223-3p (miR-223) overexpression and suppression in the target cells for functional analysis of this miRNA easily and rapidly. METHODS: The sequence that gives rise to miR-223 and the sequence generating the sponge RNA with four binding sites for miR-223 were cloned in pLVX-shRNA2 vector. The functionality of the vector to overexpress miR-223 was evaluated by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) assays, whereas the post-transcriptional regulation exerted by miR-223 was evaluated by luciferase reporter assays in AD-293 cells. The anti-miR-223 sponge activity with one binding site for miR-223 (pmCherry-anti-miR-223) was confirmed by qRT-PCR and the restoration of its target (IKKα) was evaluated by western blot assays in Jurkat cells. RESULTS: The pLVX-miR-223 vector is functional for over-expressing miR-223 and regulates the mRNA of MDR1/ABCB1 at the post-transcriptional level in AD-293 cells. The anti-miR-223 sponge with one miR-223 binding site efficiently modulates the miR-223 availability and not the one with four sites. The over-expression of anti-miR-223 correlated with a decrease in the levels of miR-223 and, consequently, with an increase in the expression level of the IKKα protein in Jurkat cells. CONCLUSIONS: This single miRNA and miRNA sponge expression system specifically alters the availability of miR-223 in mammalian cells.
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Expresión Génica , Vectores Genéticos/metabolismo , MicroARNs/metabolismo , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Subfamilia B de Transportador de Casetes de Unión a ATP/metabolismo , Regulación de la Expresión Génica/genética , Células HEK293 , Humanos , Quinasa I-kappa B/metabolismo , Células Jurkat , Lentivirus/genética , Luciferasas/genética , Células MCF-7 , MicroARNs/genéticaRESUMEN
The clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated genes (Cas) system has been rapidly harnessed to perform various genomic engineering tasks. Recently, it has been demonstrated that a novel RNA-targeting CRISPR effector protein, called Cas13, binds and cleaves RNA rather than DNA substrates analogously to the eukaryotic RNA interference system. The known Cas13a-Cas13d effectors are able to efficiently cleave complementary target single-stranded RNAs, which represent a potentially safer alternative to deoxyribonuclease Cas9, because it induces loss-of-function phenotypes without genomic loss of the targeted gene. Furthermore, through the improvement in Cas13 effector functionalities, a system called REPAIR has been developed to edit full-length transcripts containing pathogenic mutations, thus providing a promising opportunity for precise base editing. Moreover, advanced engineering of this CRISPR effector also permits nucleic acid detection, allowing the identification of mutations in cell-free tumor DNA through a platform termed Specific High Sensitivity Enzymatic Reporter Unlocking. All of these properties give us a glimpse about the potential of the CRISPR toolkit for precise transcriptome engineering, possibly leading to an expansion of CRISPR technologies for cancer therapeutics and diagnostics. Here, we examine previously unaddressed aspects of the CRISPR-based RNA-targeting approach as a feasible strategy for globally interrogating gene function in cancer in a programmable manner. Cancer Res; 78(15); 4107-13. ©2018 AACR.
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Sistemas CRISPR-Cas/genética , Neoplasias/genética , Transcriptoma/genética , ADN/genética , Edición Génica/métodos , Ingeniería Genética/métodos , Genoma/genética , Humanos , ARN/genéticaRESUMEN
The incidence of total anomalous pulmonary venous connection (TAPVC) in the Caucasian population is 2.5/100,000 live births (LB), and the incidence in the Hispanic population is 19.8/100,000 LB. Without knowing the exact etiology for the development of congenital heart disease, our objective was to determine the maternal factors associated with the development of TAPVC. METHODS: 55 mother-child binomials with isolated TAPVC (group I) and 152 healthy mother-child binomials (group II) were included. Both groups had no maternal history of addiction, pre-eclampsia, or type 1, 2 or gestational diabetes mellitus. Complete clinical histories were obtained for the women in both groups and perinatal and birth data were recorded. In addition, genealogies across three generations were constructed to determine affected first- or second-degree relatives with complex congenital heart disease. RESULTS: Among the maternal characteristics analyzed, women in group I had a higher number of pregnancies before gestation of the index case (p = <0.05), and the Body Mass Index (BMI) before pregnancy was higher compared to Group II (p < 0.05), with an adjusted risk of OR = 3.6 (p = 0.011). The family history showed a higher prevalence in the group of patients with TAPVC compared to healthy children (p < 0.05). CONCLUSION: Maternal obesity before pregnancy is a risk factor for the development of CATVP in children in the Mexican population.
Asunto(s)
Obesidad/epidemiología , Síndrome de Cimitarra/epidemiología , Adulto , Índice de Masa Corporal , Preescolar , Femenino , Cardiopatías Congénitas , Humanos , Recién Nacido , Masculino , México/epidemiología , Obesidad/patología , Paridad , Embarazo , Factores de Riesgo , Síndrome de Cimitarra/patologíaRESUMEN
The peer-review system has allowed the quality control of the manuscripts submitted for publication to scientific journals for over three centuries. However, due to its relative slowness and other drawbacks, some researchers, mainly in the areas of Physics and Mathematics, started some decades ago to propagate, by electronic means, manuscripts not yet submitted to a journal for formal publication. The dissemination of this practice led to the establishment of permanent repositories like ArXiv, to which preprints can be sent to be published whitou charge, allowing also the search and download of the works they contain with no payment required from the reader. In biomedical sciences, the adoption of the system has been slower than in the exact sciences and previous attempts like e-biomed, Netprints, and Nature Precedings did not prosper. A new generation of repositories like bioRXiv, inspired by ArXiv, seems to enjoy an increasing acceptance among biomedical researchers. Here, we discuss the potential role of this emerging system to establish discovery priority in biomedicine and to improve manuscripts before they are submitted to scientific journals besides other applications which could be implemented in the extent that the model becomes more popular.
La revisión por pares es un sistema que ha permitido el control de calidad de los manuscritos enviados para publicación en revistas científicas durante más de tres siglos. Sin embargo, debido a su relativa lentitud y otras desventajas, algunos investigadores (principalmente en las áreas de la física y las matemáticas) iniciaron hace algunas décadas la difusión electrónica de manuscritos aún no sometidos a una revista de publicación formal. La popularización de esta práctica condujo al establecimiento de repositorios permanentes como ArXiv, a los que es posible enviar preimpresiones de forma gratuita y que a la vez permiten la búsqueda y descarga de los trabajos que contienen sin cargo para el lector. En las ciencias biomédicas la adopción de este sistema ha sido más lenta que en las ciencias exactas e intentos previos como e-biomed, Netprints y Nature Precedings no prosperaron. Una nueva generación de repositorios como bioRXiv, inspirado en ArXiv, parece gozar de una creciente aceptación entre investigadores biomédicos. Aquí discutimos el potencial papel de este sistema emergente para establecer la primicia de descubrimientos en biomedicina y el mejoramiento de manuscritos antes de su sometimiento a revistas científicas, así como para otras aplicaciones que podrían implementarse en la medida en que el modelo se popularice.
Asunto(s)
Investigación Biomédica , Edición/normas , Revisión de la Investigación por Pares , ImpresiónRESUMEN
Circular RNAs (circRNAs) are a new class of long non-coding RNAs that play a potential role in gene expression regulation, acting as efficient microRNAs sponges. The latest surprise concerning circRNAs is that we now know that they can serve as transcriptional activators in human cells, indicating that circRNAs are involved in important regulatory tasks. Recently, new insight has been gained about the coding potential of circular viroid RNAs, as well as the presence of Internal Ribosomal Entry Sites (IRES) allowing the formation of peptides or proteins from circular RNA. Here, we discuss the current state of our knowledge regarding evidence supporting the hypothesis that circRNAs serve as protein-coding sequences in vitro and in vivo. Also, we remark on the difficulties of their identification and highlight some tools currently available for exploring the coding potential of circRNA.