62 research outputs found
Structure-Analysis of the HIV-1 Integrase Y143C/R Raltegravir Resistance Mutation in Association with the Secondary Mutation T97A
No full textABSTRACT
The HIV-1 integrase (IN) mutations Y143C/R are known as raltegravir (RAL) primary resistance mutations. In a previous study (S. Reigadas et al., PLoS One 5:e10311, 2010), we investigated the genetic pathway and the dynamics of emergence of the Y143C/R mutations in three patients failing RAL-containing regimens. In these patients, the Y143C/R mutation was associated with the T97A mutation. The aim of the present biochemical and molecular studies
in vitro
was to evaluate whether the secondary mutation, T97A, associated with the Y143C/R mutation could increase the level of resistance to RAL and impact IN activities. Site-directed mutagenesis experiments were performed with expression vectors harboring the region of the
pol
gene coding for IN. With a 3′-end processing assay, the 50% inhibitory concentrations (IC
50
) were 1.2 μM, 1.2 μM, 2.4 μM (fold change [FC], 2), and 20 μM (FC, 16.7) for IN wild type (WT), the IN T97A mutation, the IN Y143C/T97A mutation, and the IN Y143R/T97A mutation, respectively. FCs of 18 and 100 were observed with the strand transfer assay for IN Y143C/T97A and Y143R/T97A mutations, with IC
50
of 0.625 μM and 2.5 μM, respectively. In the strand transfer assay, the IN Y143C or R mutation combined with the secondary mutation T97A severely impaired susceptibility to RAL compared to results with the IN Y143C or R mutation alone. Assays without RAL suggested that the T97A mutation could rescue the catalytic activity which was impaired by the presence of the Y143C/R mutation. The combination of the T97A mutation with the primary RAL resistance mutations Y143C/R strongly reduces the susceptibility to RAL and rescues the catalytic defect due to the Y143C/R mutation. This result indicates that the emergence of the Y143C/R/T97A double-mutation pattern in patients is a signature of a high resistance level.
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Characterization of the gut microbiome of patients with Clostridioides difficile infection, patients with non–C. difficile diarrhea, and C. difficile–colonized patients
No full textFunding:
This study was funded by Fondo de Investigaciones Sanitarias (FIS), Research Project number PI16/00490 and PI20/01381, PFIS grant number FI21/00310, and by the European Regional Development Fund (FEDER) “A way of making Europe”.Introduction
Clostridioides difficile infection (CDI) is the main cause of nosocomial diarrhea in developed countries. A key challenge in CDI is the lack of objective methods to ensure more accurate diagnosis, especially when differentiating between true infection and colonization/diarrhea of other causes. The main objective of this study was to explore the role of the microbiome as a predictive biomarker of CDI.
Methods
Between 2018 and 2021, we prospectively included patients with CDI, recurrent CDI (R-CDI), non-CDI diarrhea (NO-CDI), colonization by C. difficile, and healthy individuals. Clinical data and fecal samples were collected. The microbiome was analyzed by sequencing the hypervariable V4 region of the 16S rRNA gene on an Illumina Miseq platform. The mothur bioinformatic pipeline was followed for pre-processing of raw data, and mothur and R were used for data analysis.
Results
During the study period, 753 samples from 657 patients were analyzed. Of these, 247 were from patients with CDI, 43 were from patients colonized with C. difficile, 63 were from healthy individuals, 324 were from NOCDI, and 76 were from R-CDI. We found significant differences across the groups in alpha and beta diversity and in taxonomic abundance. We identified various genera as the most significant biomarkers for CDI (Bacteroides, Proteus, Paraprevotella, Robinsoniella), R-CDI (Veillonella, Fusobacterium, Lactobacillus, Clostridium sensu stricto I), and colonization by C. difficile (Parabacteroides, Faecalicoccus, Flavonifractor, Clostridium XVIII).
Discussion
We observed differences in microbiome patterns between healthy individuals, colonized patients, CDI, R-CDI, and NOCDI diarrhea. We identified possible microbiome biomarkers that could prove useful in the diagnosis of true CDI infections. Further studies are warranted.European CommissionInstituto de Salud Carlos IIIMinisterio de Ciencia, Innovación y UniversidadesDepto. de Bioquímica y Biología MolecularDepto. de MedicinaDepto. de Microbiología y ParasitologíaFac. de Ciencias BiológicasFac. de MedicinaTRUEpu
Finite morphisms and simultaneous reduction of the multiplicity
No full text"This is the peer reviewed version of the following article: Abad C, Bravo A, Villamayor U. OV. Finite morphisms and simultaneous reduction of the multiplicity. Mathematische Nachrichten. 2020;293:8–38, which has been published in final form at https://doi.org/10.1002/mana.201800470. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited"Let X be a singular algebraic variety defined over a perfect field k, with quotient field K ( X ) . Let s ≥ 2 be the highest multiplicity of X and let F s ( X ) be the set of points of multiplicity s. If Y ⊂ F s ( X ) is a regular center and X ← X 1 is the blow up at Y, then the highest multiplicity of X1 is less than or equal to s. A sequence of blow ups at regular centers Y i ⊂ F s ( X i ) , say X ← X 1 ← ⋯ ← X n , is said to be a simplification of the multiplicity if the maximum multiplicity of X n is strictly lower than that of X, that is, if F s ( X n ) is empty. In characteristic zero there is an algorithm which assigns to each X a unique simplification of the multiplicity. However, the problem remains open when the characteristic is positive. In this paper we will study finite dominant morphisms between singular varieties β : X ′ → X of generic rank r ≥ 1 (i.e., [ K ( X ′ ) : K ( X ) ] = r ). We will see that, when imposing suitable conditions on β, there is a strong link between the strata of maximum multiplicity of X and X ′ , say F s ( X ) and F r s ( X ′ ) respectively. In such case, we will say that the morphism is strongly transversal. When β : X ′ → X is strongly transversal one can obtain information about the simplification of the multiplicity of X from that of X ′ and vice versa. Finally, we will see that given a singular variety X and a finite field extension L of K ( X ) of rank r ≥ 1 , one can construct (at least locally, in étale topology) a strongly transversal morphism β : X ′ → X , where X ′ has quotient field L.The authors were partially supported by the Spanish Ministry of Economy and Competitiveness, through the “Severo Ochoa” Programme for Centres of Excellence in R&D (SEV2015-0554), and through MTM2015-68524-P (MINECO/FEDER
Specific interference between two unrelated internal ribosome entry site elements impairs translation efficiency
No full textAbstractInternal ribosome entry site (IRES) elements allow simultaneous synthesis of multiple proteins in eukaryotic cells. Here, two unrelated IRESs that perform efficiently in bicistronic constructs, the picornavirus foot-and-mouth disease virus (FMDV) and the cellular immunoglobulin heavy chain binding protein (BiP) IRES, were used to generate a tricistronic vector. Functional analysis of the tricistronic RNA evidenced that the efficiency of protein synthesis under the control of BiP IRES was lower than that of the FMDV IRES, relative to the efficiency measured in bicistronic vectors. A specific competition between these elements was verified using two separate mono- or bicistronic constructs in vivo and in vitro. In contrast, no interference was detected with the hepatitis C virus (HCV) IRES. The interference effect of FMDV IRES was observed in cis and trans, in support of competition for common transacting factors different than those used in cap- and HCV-dependent initiation
Una biblioteca motivadora
No full textEl Proyecto se llevó a cabo en el CP Pintor Manuel Liaño de Barreda, participaron cinco profesores en el proyecto de los que tres asistieron a cursos de formación sobre bibliotecas escolares y el programa ABIES impartido por el CPR de Torrelavega. Los objetivos del proyecto fueron los siguientes: Organizativos: 1. Eliminar de la biblioteca aquellos libros que no se utilicen habitualmente por estar desfasados o no ser atractivos. 2. Adquirir nuevos fondos para dotarla convenientemente para los lectores a quien se dirige.3. Poseer una biblioteca moderna y hábil para ser utilizada. 4. Informatizar los volúmenes con el programa ABIES. 5. Abrir la biblioteca a padres, madres y antiguos alumnos. 6. Involucrar a la Asociación de Padres. Educativos: Crear y potenciar el hábito lector. Facilitar la continuidad de la ilusión lectora. Recuperar como lectores a los adultos que han perdido este hábito. Intentar que la biblioteca sea un foco de animación cultural para el barrio. Las actividades que se pusieron en marcha para su desarrollo fueron: Entrega de carnets de lector. Forrado de libros y pegado de tejuelos y códigos de barras. Actividades de animación a la lectura y libro fórum. Explicación de las normas de uso de la biblioteca. Préstamo de libros. Redacción de artículos para la revista escolar. Catalogación de libros e informatización de los fondos bibliográficos. Colaboración de ex-alumnos para efectuar el préstamo de libros en horario extra escolar. Préstamo de libros. En el anexo se puede consultar los resultados de las encuestas realizadas y también las peticiones de los alumnos antes de comenzar con el proyecto. Los materiales utilizados fueron: ordenador, material infotmático, material de papelería.Gobierno de Cantabria. Consejería de Educación y JuventudES
Recours au test de résistance génotypique sur ADN VIH : Consensus Français de type DELPHI
No full textInternational audienceAbstract Covid-19 has spurred a renewed interest in decontamination techniques for air, objects and surfaces. Beginning in 2020, urgent effort was done to permit the reuse of UV-C for inactivating SARS-CoV-2. However, those studies diverged widely on the dose necessary to reach this goal; until today, the real value of the sensitivity of the virus to a 254-nm illumination is not known precisely. In this study, decontamination was performed in an original UV-C large decontamination chamber (UVCab, ON-LIGHT, France) delivering an omnidirectional irradiation with an average dose of 50 mJ/cm 2 in 60 s. Viral inactivation was checked by both cell culture and PCR test. SARS-CoV-2 was inactivated by UV-C light within 3 s on both porous (disposable gown) and non-porous (stainless steel and apron) surfaces. For the porous surface, an irradiation of 5 min was needed to achieve a completely negative PCR signal. The Z value estimating the sensitivity of SARS-CoV-2 to UV-C in the experimental conditions of our cabinet was shown to be > 0.5820 m 2 /J. These results illustrate the ability of this apparatus to inactivate rapidly and definitively high loads of SARS-CoV-2 deposited on porous or non-porous supports and opens new perspectives on material decontamination using UV-C
Hepatitis C virus (HCV) protease variability and anti-HCV protease inhibitor resistance in HIV/HCV-coinfected patients
No full textInternational audienceOBJECTIVES: Data on the natural selection of isolates harbouring mutations within the NS3 protease, conferring resistance to hepatitis C virus (HCV) protease inhibitors (PIs), are limited for HIV/HCV-coinfected patients. The aim of this study was to describe the natural prevalence of mutations conferring resistance to HCV PIs in HIV/HCV-coinfected patients compared with HCV-monoinfected patients. METHODS: The natural prevalences of HCV PI resistance mutations in 120 sequences from HIV/HCV-coinfected patients (58 genotype 1a, 18 genotype 1b and 44 genotype 4) and 501 sequences from HCV-monoinfected patients (476 genotype 1 and 25 genotype 4), retrieved from GenBank as a control group, were compared. RESULTS: Of 76 sequences from HIV/HCV genotype 1-coinfected patients, six (7.9%) showed amino acid substitutions associated with HCV PI resistance (V36L, n=1; V36M, n=2; T54S, n=2; R155K, n=1). In 31 of 476 (6.5%) HCV genotype 1 sequences retrieved from the GenBank database, HCV PI resistance mutations were found. The difference was not statistically significant (P=0.6). All of the sequences from HIV/HCV genotype 4-coinfected patients and those retrieved from the GenBank database had amino acid changes at position 36 (V36L). CONCLUSION: Our study suggests that the natural prevalence of strains resistant to HCV PIs does not differ between HCV-monoinfected and HIV/HCV-coinfected patients. Further studies on larger cohorts are needed to confirm these findings and to evaluate the impact of these mutations in clinical practice
Fecal microbiota transplantation for recurrent Clostridium difficile infection: Experience, protocol, and results.
No full textFecal microbiota transplantation (FMT) is a highly effective therapy for recurrent Clostridium difficile infection (R-CDI). Despite its excellent efficacy, it is still not a routine procedure in most European centers. FMT has not been widely used in Spain to date. We describe our experience with FMT, including a novel approach based on oral fecal capsules
Telemedicine networks of EHAS Foundation in Latin America
No full textRural areas in developing countries are characterized by lack of resources, low population density and scarcity of communications infrastructure. These circumstances make it difficult to provide appropriate healthcare services. This paper explains research results achieved by EHAS (Enlace Hispano Americano de Salud - Hispano American Health Link) and how they have contributed to improve healthcare in isolated areas of developing countries through the use of Information and Communication Technologies (ICT). As the first step, EHAS always collaborates with public health systems to identify its communication and information needs. Based on the analysis of needs, EHAS does research on appropriate technologies to provide communication in each context and on information systems suited to needs of health personnel. In parallel, EHAS has worked to provide applications that, making use of the communications services installed, could improve the healthcare services in these remote areas. In this line, solutions to improve epidemiological surveillance or to provide telemedicine services (like a digital stethoscope or a tele-microscopy system) have been developed. EHAS has also performed several researches trying to ensure the sustainability of their solutions and has summarized them in a Management Framework for Sustainable e-Healthcare Provision. Finally, the effort to spread acquired knowledge has crystallized in a book that details all the technologies and procedures previously mentioned
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