129 research outputs found
A link between nuclear RNA surveillance, the human exosome and RNA polymerase II transcriptional termination
In eukaryotes, the production of mature messenger RNA that exits the nucleus to be translated into protein in the cytoplasm requires precise and extensive modification of the nascent transcript. Any failure that compromises the integrity of an mRNA may cause its retention in the nucleus and trigger its degradation. Multiple studies indicate that mRNAs with processing defects accumulate in nuclear foci or ‘dots’ located near the site of transcription, but how exactly are defective RNAs recognized and tethered is still unknown. Here, we present evidence suggesting that unprocessed β-globin transcripts render RNA polymerase II (Pol II) incompetent for termination and that this quality control process requires the integrity of the nuclear exosome. Our results show that unprocessed pre-mRNAs remain tethered to the DNA template in association with Pol II, in an Rrp6-dependent manner. This reveals an unprecedented link between nuclear RNA surveillance, the exosome and Pol II transcriptional termination
Toward a clinical practice guide in pharmacogenomics testing for functional polymorphisms of drug-metabolizing enzymes. Gene/drug pairs and barriers perceived in Spain
The development of clinica lpractice recommendations or
guidelines for the clinical use of biomarkers is an issue of great importance withr regard to adverse drug reactions.The poten-tial of pharmacogenomicbiomarkers has been extensively investigated in recent years.However,several barriers to implementing the use of pharmacogenomics testing exist.We conducted a survey among members of the Spanish Societies of Pharmacology and Clinical Pharmacology to obtain information about the perception of such barriers and to compare the perceptions of participants about the relative importance of majorgene/drug pairs.Of 11 potential barriers,the highest importance was attributed to lack of institutional support for pharmacogenomic stesting,and to the issues related to the lack of guidelines.Of the proposed gene/drug pairs the highest importance was assigned to HLA-B/abacavir, UGT1A1/irinotecan, and CYP2D6/tamoxifen.In this perspective article,we compare the relative importance of 29 gene/drugpairs in the Spanish study with that of the same pairs in the American Society for Clinical Pharmacology and Therapeutic sstudy,and we provide suggestions and areas of focus to develop a guide for clinical practice in pharmacogenomics testingThe work in the author’s laboratory is financed by Grants
PS09/00943, PS09/00469, RETICS RIRAAF RD07/0064/0016,
and CIBERehd from Instituto de Salud CarlosIII,Madrid,
Spain, and by Grants GR10068 from Junta de Extremadura,
Spain. Financed in part with FEDER funds from the European
Unio
Separation of Isomeric Forms of Urolithin Glucuronides Using Supercritical Fluid Chromatography
Producción CientíficaUrolithins are gut microbiota metabolites produced in humans after consuming foods containing ellagitannins and ellagic acid. Three urolithin metabotypes have been reported for different individuals depending on the final urolithins produced. After absorption, they are conjugated with glucuronic acid (phase II metabolism), and these are the main circulating metabolites in plasma and reach different tissues. Different regioisomeric isomers of urolithin glucuronides have been described. Still, their identification and quantification in humans have not been properly reported due to resolution limitations in their analysis by reversed-phase high-performance liquid chromatography. In the present study, we report a novel method for separating these isomers using supercritical fluid chromatography. With this method, urolithin A 3- and 8-glucuronide, isourolithin A 3- and 9- glucuronide, and urolithin B 3-glucuronide (8-hydroxy urolithin 3-glucuronide; 3-hydroxy urolithin 8-glucuronide; 3-hydroxyurolithin 9-glucuronide; 9-hydroxyurolithin 3-glucuronide; and urolithin 3-glucuronide) were separated in less than 15 min. The proposed method was applied to successfully analyze these metabolites in urine samples from different volunteers belonging to different metabotypes.Taif University (TURSP- HC2021/3
Differentiation of bee pollen samples according to their intact-glucosinolate content using canonical discriminant analysis
Producción CientíficaA study is presented of the real possibilities of glucosinolate content and chemometrics (canonical discriminant analysis) to differentiate bee pollen samples from four different apiaries (Fuentelahiguera, Monte, Pistacho, Tío Natalio) located in the same geographical area. Fifteen intact-glucosinolates were quantified by means of ultraperformance liquid chromatography coupled to a quadrupole time-of-flight mass detector in forty-nine bee pollen samples. Glucosinolate residues were detected in most of the samples, and these differed in number and concentration. It was possible to directly differentiate one of the apiaries (Fuentelahiguera) from the other three (Monte, Pistacho y Tío Natalio) by comparing glucosinolate content. These three apiaries were differentiated by means of the first two canonical variables obtained from a canonical discriminant analysis. Following this analysis, more than 88% of the samples could be assigned correctly to the Pistacho and Monte apiaries, and 100% to the Tío Natalio apiary.Este trabajo forma parte de los proyectos de investigación financiados por el Ministerio de Economía y Competitividad e INIA-FEDER (RTA2015-00013-C03-01 y 03)
Estudio de la estabilidad de aptámeros generados frente a la proteína 4E-BP1
El control de la síntesis de proteínas juega un papel importante en el crecimiento y proliferación celular. En la mayoría de los organismos eucariotas se lleva a cabo una traducción dependiente de cap en la cual el factor eucariótico de iniciación (eIF) 4E juega un papel muy importante. La actividad de este factor está regulada por la proteína 4E-BP1 (proteína de unión a eIF4E), entre otras, cuya fosforilación permite la liberación del factor y su participación en la traducción. La sobreexpresión del factor eIF4E produce irregularidades en el ciclo celular relacionadas con el cáncer, enfermedad que produce 8.2 millones de muertes anuales en el mundo. La actividad reguladora de la proteína 4E-BP1 la convierte en una posible diana terapéutica, por lo que en el laboratorio se seleccionaron tres aptámeros frente a dicha proteína a través del método SELEX. Los aptámeros se conocen como 1R, 1F y 20F y poseen estructuras secundarias complejas y con posibilidad de formación de G-cuádruplex, lo que les confiere una alta estabilidad. Por ello en el presente trabajo se ha ampliado la caracterización estructural y funcional de estos aptámeros mediante parámetros como susceptibilidad a nucleasas, IC50, niveles intracelulares, efecto sobre la síntesis de proteínas y constante de disociación. Los resultados posicionan a los aptámeros 1R y 20F como los más estables y los principales candidatos como potenciales herramientas terapéuticas. Sin embargo, es necesario realizar nuevos experimentos funcionales así como estudiar la especificidad de los aptámeros frente a otras proteínas y otros aspectos importantes para su aplicación clínic
Diminished neurogenic femoral artery vasoconstrictor response in a Zucker obese rat model: differential regulation of NOS and COX derivatives
Objective: Peripheral arterial disease is one of the macrovascular complications of type 2 diabetes mellitus. This study addresses femoral artery regulation in a prediabetic model of obese Zucker rats (OZR) by examining cross-talk between endothelial and neural factors. Methods and Results: Arterial preparations from lean (LZR) and OZR were subjected to electrical field stimulation (EFS) on basal tone. Nitric oxide synthase (NOS) and cyclooxygenase (COX) isoform expression patterns were determined by immunohistochemical labelling and Western blotting. Results indicate significantly reduced noradrenergic contractions in preparations from OZR compared with those of LZR. Functional inhibition of endothelial NOS (eNOS) indicated a predominant role of this isoform in LZR and its modified activity in OZR. Neural (nNOS) and inducible NOS (iNOS) were activated and their expression was higher in femoral arteries from OZR. Neurotransmission modulated by largeconductance Ca2+-activated (BKCa) or voltage-dependent (KV) K+ channels did not seem compromised in the obese animals. Endothelial COX-1 and COX-2 were expressed in LZR and an additional adventitial location of COX-2 was also observed in OZR, explaining the higher COX-2 protein levels detected in this group. Prostanoids derived from both isoforms helped maintain vasoconstriction in LZR while in OZR only COX-2 was active. Superoxide anion inhibition reduced contractions in endothelium-intact arteries from OZR. Conclusions: Endothelial dysfunction led to reduced neurogenic vasoconstriction in femoral arteries from OZR. In a setting of obesity, NO-dependent nNOS and iNOS dilation activity could be an alternative mechanism to offset COX-2- and reactive oxygen species-mediated vasoconstriction, along with impaired endothelial NO relaxation
Differentiation of bee pollen samples according to the apiary of origin and harvesting period based on their amino acid content
Producción CientíficaBee pollen is currently one of the most widely consumed dietary supplements due to its high nutritional value and its potentially beneficial effects on health. Unfortunately, in recent years an increase in the fraudulent marketing of this product has been detected, mainly in terms of adulteration with pollen from other sources. This has made it necessary to seek new tools to ensure its authentication. Therefore, this study investigates the use of free amino acids as markers of the geographical origin and harvesting period of bee pollen. To demonstrate their potential as biomarkers, 72 samples from four apiaries (Pistacho, Tío Natalio, Monte and Fuentelahiguera), located in the same geographical area (Marchamalo, Guadalajara, Spain), were analyzed by liquid chromatography-fluorescence detection, with the data obtained undergoing canonical discriminant analysis. Variable amounts and numbers of free amino acids were found in the samples analyzed; proline predominated in all of them, in a concentration range of 298–569989 mg/kg. The differences observed in amino acid composition could be attributed to the flowering plants from which the bee pollen samples originated. In addition, it was possible to statistically assign over 75% of the samples to the corresponding apiary of origin, the best results being obtained for the Fuentelahiguera and Tío Natalio apiaries (100%); this classification was even superior in the case of the harvesting periods, as more than 90% of the samples were correctly assigned, and in one period (June) a 100% rate was obtained.Ministerio de Economía, Industria y Competitividad (projects RTA 2015-00013-C03-01 and RTA 2015-00013-C03-03
Sostenibilidad curricular de titulaciones universitarias: un proyecto del Grupo SAC-UBU para conocer la percepción del alumnado de la Facultad de Ciencias
Póster presentado en: VIII Jornadas de Innovación Docente de la UBU, Burgos, 5 de abril de 2016, organizadas por el Instituto de Formación e Innovación Educativa-IFIE de la Universidad de Burgo
A critical view on the current use of daptomycin in Spain: The daptomise study
Background: The Study on the Clinical Use of DAPTOMycin in Spain (DAPTOMISE Study) is a national surveillance program of daptomycin use. The objectives of this study are to evaluate the current variability in daptomycin consumption across the different hospitals and the adequacy of therapy, specially focused on underdosing. Methods: All adult and pediatric patients who received, at least, one dose of daptomycin in a single week in 98 institutions in Spain were included. The adequacy of daptomycin use was evaluated with respect to the indication, dosage, adjustments after microbiology results, switching to an oral agent and length of treatment. Results: A total of 615 patients received daptomycin during the study week. The prevalence use was 2.3 patients / 100,000 inhabitants per week, 12.4 patients / 1000 admissions and 9.2 Days of Therapy (DOT) / 1000 hospital stays. These rates varied between hospitals: from 0 to 13.9 patients / 100,000 inhabitants, from 0 to 76.1 patients / 1000 admissions and from 0 to 49.4 DOT / 1000 hospital stays. The most frequent infections were bacteremia (31.6 %) and skin and soft tissue infections (17.9 %). Microbiological results were available in only 65.4 % of infections. The most frequent microorganisms were Staphylococcus aureus (192 isolates, of which 87 were resistant to methicillin) and coagulase-negative staphylococci (124 isolates). A total of 136 prescriptions (22.1 %) were underdosed. Dosages < 8 mg/kg were used for 35.6 % of endovascular infections and for 26.2 % of osteoarticular infections. Overall, 57.2 % of prescriptions were not optimal in, at least, one item. Clinical cure rate was 76.1% and mortality attributable to the infection 8.1%. Conclusion: This is the first registry that identifies the prevalence of use of daptomycin in Spain and shows a high variability in the consumption between the different hospitals. Daptomycin underdosing was present in more than 20 % of cases. (c) 2023 Published by Elsevier Ltd on behalf of King Saud Bin Abdulaziz University for Health Sciences. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)
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