1,987 research outputs found
Neoflavonoids as Inhibitors of HIV-1 Replication by Targeting the Tat and NF-kB Pathways
Twenty-eight neoflavonoids have been prepared and evaluated in vitro against HIV-1.
Antiviral activity was assessed on MT-2 cells infected with viral clones carrying the luciferase reporter
gene. Inhibition of HIV transcription and Tat function were tested on cells stably transfected with the
HIV-LTR and Tat protein. Seven 4-phenylchromen-2-one derivatives showed HIV transcriptional
inhibitory activity but only the phenylchrome-2-one 10 inhibited NF- B and displayed anti-Tat activity
simultaneously. Compounds 10, 14, and 25, inhibited HIV replication in both targets at concentrations
<25 M. The assays of these synthetic 4-phenylchromen-2-ones may aid in the investigation of some
aspects of the anti-HIV activity of such compounds and could serve as a scaffold for designing better
anti-HIV compounds, which may lead to a potential anti-HIV therapeutic dru
EVALUACIÓN IN VITRO DE LA EFICACIA ANTIFÚNGICA DEL HIDRÓXIDO DE CALCIO EN AGUA DESTILADA Y DEL GEL DE DIGLUCONATO DE CLORHEXIDINA AL 0.2% COMO MEDICACIÓN INTRACONDUCTO FRENTE A CANDIDA ALBICANS
Purpose: To evaluate the effectiveness in vitro of Ca(OH)2 paste in distilled water and cholrhexidine digluconate gel (CHX) up to 0.2% separately as induct medications forehead Candida albicans roots of extracted human teeth.Materials and methods: By means of an experimental study in vitro in which 45 dental roots were used, previously inoculated with Candida albicans ATCC6455017 during 72 hours and that later were medicated intracanal with Ca(OH)2 paste (Eufar®) in distilled water p/v 50% and CHX digluconate gel up to 0.2%. (Perioxidin®), during seven days. In the next step each radicular specimen was instrumented with Hedstrom files of the second series in order to obtain dentine mud of the radicular channel system, which is diluted in 5 ml of soy tripticasa spreaded on agar saboraud up to 2% during 72 hours to 37ºC to determine (UFC/mL) of this yeast.Results: The study showed that the effectiveness of the Ca(OH)2 paste is 62.5% and the one of the CHX digluconate gel was 6.25%. Besides that the ANOVA revealed differences statistically significants (p=0.0013) between the averages of UFC/ml of Candida albicans among that medications. Also, the Bonferroni test established significant differences among the UFC/mL averages of Candida albicans after medicated with Ca(OH)2 compared with CHX gel up to 2%. (p=0.002) and the control group (p=0.010). However, there were not found significant differences in the treatment with CHX gel and the control group.Conclusions: Candida albicans is able to settle down in the interior of the canal’s system and interacts with dentine.Objetivo: Evaluar la eficacia in vitro de la pasta de Ca(OH)2 en agua destilada y gel de digluconato de clorhexidina (CHX) al 0.2%, separadamente, como medicaciones intraconducto frente a Candida albicans en raíces de dientes humanos extraídos.Materiales y métodos: Mediante un estudio experimental in vitro, en el que se utilizaron 45 raíces uniradiculares, previamente inocula-das con Candida albicans, ATCC6455017 durante 72 horas y que luego fueron medicadas intraconducto con pasta de Ca(OH)2 (Eufar®) en agua destilada p/v 50% y con gel de digluconato de clorhexidina al 0.2% (Perioxidin®), durante 7 días; en el siguiente paso, cada espécimen radicular fue instrumentado con limas Hedstrom de la segunda serie para obtener barrillo dentinario del sistema del canales radiculares, el cual se diluye en 5 ml de tripticasa soya que se siembra en agar saboraud al 2%, durante 72 horas a 37°C, para determinar (UFC/ml) de esta levadura.Resultado: La eficacia de la pasta de Ca(OH)2 fue del 62.5% y la del gel de CHX al 0.2% fue de 6.25%. El ANOVA reveló diferencias esta-dísticamente significativas (p=0.0013) entre los promedios de UFC/ml de Candida albicans, entre las medicaciones. También, el test de Bonferroni estableció diferencias significativas entre los promedios de UFC/ml de Candida albicans después de medicar con pasta de Ca(OH)2comparado con gel de CHX al 0.2% (p=0.002) y el grupo control (p=0.010). Sin embargo, no se encontraron diferencias significativas entre el tratamiento con gel de CHX al 0.2% y el grupo control.Conclusiones: Se demostró, in vitro, que Candida albicans es capaz de establecerse al interior del sistema del canal radicular e interactuar con la dentina.[Bedoya LF, Niño MP, Peña CM, Toloza E. Evaluación in vitro de la eficacia antifúngica del hidróxido de calcio en agua destilada y del gel de digluconato de clorhexidina al 0.2% como medicación intraconducto frente a Candida albicans. Ustasalud 2008; 7: 77 - 86
Exploring the HIV-1 Rev Recognition Element (RRE)-Rev Inhibitory Capacity and Antiretroviral Action of Benfluron Analogs
Human immunodeficiency virus-type 1 (HIV-1) remains one of the leading contributors to the global burden of disease, and novel antiretroviral agents with alternative mechanisms are needed to cure this infection. Here, we describe an exploratory attempt to optimize the antiretroviral properties of benfluron, a cytostatic agent previously reported to exhibit strong anti-HIV activity likely based on inhibitory actions on virus transcription and Rev-mediated viral RNA export. After obtaining six analogs designed to modify the benzo[c]fluorenone system of the parent molecule, we examined their antiretroviral and toxicity properties together with their capacity to recognize the Rev Recognition Element (RRE) of the virus RNA and inhibit the RRE-Rev interaction. The results indicated that both the benzo[c] and cyclopentanone components of benfluron are required for strong RRE-Rev target engagement and antiretroviral activity and revealed the relative impact of these moieties on RRE affinity, RRE-Rev inhibition, antiviral action and cellular toxicity. These data provide insights into the biological properties of the benzo[c]fluorenone scaffold and contribute to facilitating the design of new anti-HIV agents based on the inhibition of Rev function.This research was funded by Generalitat Valenciana of Spain (PROMETEO 2021/036 grant to J.G. and GRISOLIAP/2020/026 contract to M.P.S.), MCIN/AEI/10.13039/501100011033 of Spain and “ERDF A way of making Europe” (grants PID2020-117508RB-I00 to V.M., RTI2021-093935-B-I00 to J.G., PID2021-125978OB-C2 to J.A. and PID2019-109870RB-I00 and CB21/13/00063 to J.M.-P.).S
4-Deoxyphorbol inhibits HIV-1 infection in synergism with antiretroviral drugs and reactivates viral reservoirs through PKC/MEK activation synergizing with vorinostat.
Latent HIV reservoirs are the main obstacle to eradicate HIV infection. One strategy proposes to eliminate these viral reservoirs by pharmacologically reactivating the latently infected T cells. We show here that a 4-deoxyphorbol ester derivative isolated from Euphorbia amygdaloides ssp. semiperfoliata, 4β-dPE A, reactivates HIV-1 from latency and could potentially contribute to decrease the viral reservoir. 4β-dPE A shows two effects in the HIV replication cycle, infection inhibition and HIV transactivation, similarly to other phorboids PKC agonists such PMA and prostratin and to other diterpene esters such SJ23B. Our data suggest 4β-dPE A is non-tumorigenic, unlike the related compound PMA. As the compounds are highly similar, the lack of tumorigenicity by 4β-dPE A could be due to the lack of a long side lipophilic chain that is present in PMA. 4β-dPE activates HIV transcription at nanomolar concentrations, lower than the concentration needed by other latency reversing agents (LRAs) such as prostratin and similar to bryostatin. PKCθ/MEK activation is required for the transcriptional activity, and thus, anti-latency activity of 4β-dPE A. However, CD4, CXCR4 and CCR5 receptors down-regulation effect seems to be independent of PCK/MEK, suggesting the existence of at least two different targets for 4β-dPE A. Furthermore, NF-κb transcription factor is involved in 4β-dPE HIV reactivation, as previously shown for other PKCs agonists. We also studied the effects of 4β-dPE A in combination with other LRAs. When 4β-dPE A was combined with another PKC agonists such as prostratin an antagonic effect was achieved, while, when combined with an HDAC inhibitor such as vorinostat, a strong synergistic effect was obtained. Interestingly, the latency reversing effect of the combination was synergistically diminishing the EC50 value but also increasing the efficacy showed by the drugs alone. In addition, combinations of 4β-dPE A with antiretroviral drugs as CCR5 antagonist, NRTIs, NNRTIs and PIs, showed a consistent synergistic effect, suggesting that the combination would not interefer with antiretroviral therapy (ART). Finally, 4β-dPE A induced latent HIV reactivation in CD4 + T cells of infected patients under ART at similar levels than the tumorigenic phorbol derivative PMA, showing a clear reactivation effect. In summary, we describe here the mechanism of action of a new potent deoxyphorbol derivative as a latency reversing agent candidate to decrease the size of HIV reservoirs.This work was supported by Ministry of Education of the Peruvian government (PRONABEC), the Universidad Complutense de Madrid (UCM-Santander PR87/19), the Instituto de Salud Carlos III (ISCIII-FIS PI16CIII/00034) and the Spanish AIDS Research Network RD12/0017/0015 that is included in the Spanish I D I Plan and is co-financed by ISCIII-Subdirección General de Evaluación and European Funding for Regional Development (FEDER). This work has also benefited from an “Investissement d’Avenir” grant managed by Agence Nationale de la Recherche (CEBA, ANR- 10-LABX-25-01).S
3-Phenylcoumarins as Inhibitors of HIV-1 Replication
We have synthesized fourteen 3-phenylcoumarin derivatives and evaluated their
anti-HIV activity. Antiviral activity was assessed on MT-2 cells infected with viral clones
carrying the luciferase gene as reporter. Inhibition of HIV transcription and Tat function
were tested on cells stably transfected with the HIV-LTR and Tat protein. Six compounds
displayed NF-κB inhibition, four resulted Tat antagonists and three of them showed both
activities. Three compounds inhibited HIV replication with IC50 values < 25 μM. The
antiviral effect of the 4-hydroxycoumarin derivative 19 correlates with its specific
inhibition of Tat functions, while compound 8, 3-(2-chlorophenyl)coumarin, seems to act
through a mechanism unrelated to the molecular targets considered in this research
Ground/space, passive/active remote sensing observations coupled with particle dispersion modelling to understand the inter-continental transport of wildfire smoke plumes
During the 2017 record-breaking burning season in Canada/United States, intense wild fires raged during the first week of September in the Pacific northwestern region (British Columbia, Alberta, Washington, Oregon, Idaho, Montana and northern California) burning mostly temperate coniferous forests. The heavy loads of smoke particles emitted in the atmosphere reached the Iberian Peninsula (IP) a few days later on 7 and 8 September. Satellite imagery allows to identify two main smoke clouds emitted during two different periods that were injected and transported in the atmosphere at several altitude levels. Columnar properties on 7 and 8 September at two Aerosol Robotic Network (AERONET) mid-altitude, background sites in northern and southern Spain are: aerosol optical depth (AOD) at 440 nm up to 0.62, Ångström exponent of 1.6–1.7, large dominance of small particles (fine mode fraction >0.88), low absorption AOD at 440 nm (0.98). Profiles from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) show the presence of smoke particles in the stratosphere during the transport, whereas the smoke is only observed in the troposphere at its arrival over the IP. Portuguese and Spanish ground lidar stations from the European Aerosol Research Lidar Network/Aerosols, Clouds, and Trace gases Research InfraStructure Network (EARLINET/ACTRIS) and the Micro-Pulse Lidar NETwork (MPLNET) reveal smoke plumes with different properties: particle depolarization ratio and color ratio, respectively, of 0.05 and 2.5 in the mid troposphere (5–9 km) and of 0.10 and 3.0 in the upper troposphere (10–13 km). In the mid troposphere the particle depolarization ratio does not seem time-dependent during the transport whereas the color ratio seems to increase (larger particles sediment first). To analyze the horizontal and vertical transport of the smoke from its origin to the IP, particle dispersion modelling is performed with the Hybrid Single Particle Lagrangian Integrated Trajectory Model (HYSPLIT) parameterized with satellite-derived biomass burning emission estimates from the Global Fire Assimilation System (GFAS) of the Copernicus Atmosphere Monitoring Service (CAMS). Three compounds are simulated: carbon monoxide, black carbon and organic carbon. The results show that the first smoke plume which travels slowly reaches rapidly (~1 day) the upper troposphere and lower stratosphere (UTLS) but also shows evidence of large scale horizontal dispersion, while the second plume, entrained by strong subtropical jets, reaches the upper troposphere much slower (~2.5 days). Observations and dispersion modelling all together suggest that particle depolarization properties are enhanced during their vertical transport from the mid to the upper troposphere.Spanish groups acknowledge the Spanish Ministry of Economy and Competitivity (MINECO) (ref. CGL2013-45410-R, CGL2014-52877-R, CGL2014-55230-R, TEC2015-63832-P, CGL2015-73250-JIN, CGL2016-81092-R and CGL2017-85344-R)European Union through H2020 programme ACTRIS-2, grant 654109European Union through H2020 programme EUNADICS-AV, grant 723986European Union through H2020 programme GRASP-ACE, grant 77834
Native American ancestry significantly contributes to neuromyelitis optica susceptibility in the admixed Mexican population
Neuromyelitis Optica (NMO) is an autoimmune disease with a higher prevalence in non-European populations. Because the Mexican population resulted from the admixture between mainly Native American and European populations, we used genome-wide microarray, HLA high-resolution typing and AQP4 gene sequencing data to analyze genetic ancestry and to seek genetic variants conferring NMO susceptibility in admixed Mexican patients. A total of 164 Mexican NMO patients and 1,208 controls were included. On average, NMO patients had a higher proportion of Native American ancestry than controls (68.1% vs 58.6%; p = 5 × 10–6). GWAS identified a HLA region associated with NMO, led by rs9272219 (OR = 2.48, P = 8 × 10–10). Class II HLA alleles HLA-DQB1*03:01, -DRB1*08:02, -DRB1*16:02, -DRB1*14:06 and -DQB1*04:02 showed the most significant associations with NMO risk. Local ancestry estimates suggest that all the NMO-associated alleles within the HLA region are of Native American origin. No novel or missense variants in the AQP4 gene were found in Mexican patients with NMO or multiple sclerosis. To our knowledge, this is the first study supporting the notion that Native American ancestry significantly contributes to NMO susceptibility in an admixed population, and is consistent with differences in NMO epidemiology in Mexico and Latin America.Fil: Romero Hidalgo, Sandra. Instituto Nacional de Medicina Genómica; MéxicoFil: Flores Rivera, José. Instituto Nacional de Neurología y Neurocirugía; MéxicoFil: Rivas Alonso, Verónica. Instituto Nacional de Neurología y Neurocirugía; MéxicoFil: Barquera, Rodrigo. Max Planck Institute For The Science Of Human History; Alemania. Instituto Nacional de Antropología e Historia; MéxicoFil: Villarreal Molina, María Teresa. Instituto Nacional de Medicina Genómica; MéxicoFil: Antuna Puente, Bárbara. Instituto Nacional de Medicina Genómica; MéxicoFil: Macias Kauffer, Luis Rodrigo. Universidad Nacional Autónoma de México; MéxicoFil: Villalobos Comparán, Marisela. Instituto Nacional de Medicina Genómica; MéxicoFil: Ortiz Maldonado, Jair. Instituto Nacional de Neurología y Neurocirugía; MéxicoFil: Yu, Neng. American Red Cross; Estados UnidosFil: Lebedeva, Tatiana V.. American Red Cross; Estados UnidosFil: Alosco, Sharon M.. American Red Cross; Estados UnidosFil: García Rodríguez, Juan Daniel. Instituto Nacional de Medicina Genómica; MéxicoFil: González Torres, Carolina. Instituto Nacional de Medicina Genómica; MéxicoFil: Rosas Madrigal, Sandra. Instituto Nacional de Medicina Genómica; MéxicoFil: Ordoñez, Graciela. Neuroimmunología, Instituto Nacional de Neurología y Neurocirugía; MéxicoFil: Guerrero Camacho, Jorge Luis. Instituto Nacional de Neurología y Neurocirugía; MéxicoFil: Treviño Frenk, Irene. American British Cowdray Medical Center; México. Instituto Nacional de la Nutrición Salvador Zubiran; MéxicoFil: Escamilla Tilch, Monica. Instituto Nacional de la Nutrición Salvador Zubiran; MéxicoFil: García Lechuga, Maricela. Instituto Nacional de la Nutrición Salvador Zubiran; MéxicoFil: Tovar Méndez, Víctor Hugo. Instituto Nacional de la Nutrición Salvador Zubiran; MéxicoFil: Pacheco Ubaldo, Hanna. Instituto Nacional de Antropología E Historia. Escuela Nacional de Antropología E Historia; MéxicoFil: Acuña Alonzo, Victor. Instituto Nacional de Antropología E Historia. Escuela Nacional de Antropología E Historia; MéxicoFil: Bortolini, María Cátira. Universidade Federal do Rio Grande do Sul; BrasilFil: Gallo, Carla. Universidad Peruana Cayetano Heredia; PerúFil: Bedoya Berrío, Gabriel. Universidad de Antioquia; ColombiaFil: Rothhammer, Francisco. Universidad de Tarapacá; ChileFil: Gonzalez-Jose, Rolando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Ciencias Sociales y Humanas; ArgentinaFil: Ruiz Linares, Andrés. Colegio Universitario de Londres; Reino UnidoFil: Canizales Quinteros, Samuel. Universidad Nacional Autónoma de México; MéxicoFil: Yunis, Edmond. Dana Farber Cancer Institute; Estados UnidosFil: Granados, Julio. Instituto Nacional de la Nutrición Salvador Zubiran; MéxicoFil: Corona, Teresa. Instituto Nacional de Neurología y Neurocirugía; Méxic
Reconstructing Native American Population History
The peopling of the Americas has been the subject of extensive genetic, archaeological and linguistic research; however, central questions remain unresolved1–5. One contentious issue is whether the settlement occurred via a single6–8 or multiple streams of migration from Siberia9–15. The pattern of dispersals within the Americas is also poorly understood. To address these questions at higher resolution than was previously possible, we assembled data from 52 Native American and 17 Siberian groups genotyped at 364,470 single nucleotide polymorphisms. We show that Native Americans descend from at least three streams of Asian gene flow. Most descend entirely from a single ancestral population that we call “First American”. However, speakers of Eskimo-Aleut languages from the Arctic inherit almost half their ancestry from a second stream of Asian gene flow, and the Na-Dene-speaking Chipewyan from Canada inherit roughly one-tenth of their ancestry from a third stream. We show that the initial peopling followed a southward expansion facilitated by the coast, with sequential population splits and little gene flow after divergence, especially in South America. A major exception is in Chibchan-speakers on both sides of the Panama Isthmus, who have ancestry from both North and South America
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Genome-wide association study of Tourette Syndrome
Tourette Syndrome (TS) is a developmental disorder that has one of the highest familial recurrence rates among neuropsychiatric diseases with complex inheritance. However, the identification of definitive TS susceptibility genes remains elusive. Here, we report the first genome-wide association study (GWAS) of TS in 1285 cases and 4964 ancestry-matched controls of European ancestry, including two European-derived population isolates, Ashkenazi Jews from North America and Israel, and French Canadians from Quebec, Canada. In a primary meta-analysis of GWAS data from these European ancestry samples, no markers achieved a genome-wide threshold of significance (p<5 × 10−8); the top signal was found in rs7868992 on chromosome 9q32 within COL27A1 (p=1.85 × 10−6). A secondary analysis including an additional 211 cases and 285 controls from two closely-related Latin-American population isolates from the Central Valley of Costa Rica and Antioquia, Colombia also identified rs7868992 as the top signal (p=3.6 × 10−7 for the combined sample of 1496 cases and 5249 controls following imputation with 1000 Genomes data). This study lays the groundwork for the eventual identification of common TS susceptibility variants in larger cohorts and helps to provide a more complete understanding of the full genetic architecture of this disorder
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