25 research outputs found
ISCOM-like nanoparticles formulated with Quillaja brasiliensis Saponins are promising adjuvants for seasonal influenza vaccines
Vaccination is the most effective public health intervention to prevent influenza infections, which are responsible for an important burden of respiratory illnesses and deaths each year. Currently, licensed influenza vaccines are mostly split inactivated, although in order to achieve higher efficacy rates, some influenza vaccines contain adjuvants. Although split-inactivated vaccines induce mostly humoral responses, tailoring mucosal and cellular immune responses is crucial for preventing influenza infections. Quillaja brasiliensis saponin-based adjuvants, including ISCOM-like nanoparticles formulated with the QB-90 saponin fraction (IQB90), have been studied in preclinical models for more than a decade and have been demonstrated to induce strong humoral and cellular immune responses towards several viral antigens. Herein, we demonstrate that a split-inactivated IQB90 adjuvanted influenza vaccine triggered a protective immune response, stronger than that induced by a commercial unadjuvanted vaccine, when applied either by the subcutaneous or the intranasal route. Moreover, we reveal that this novel adjuvant confers up to a ten-fold dose-sparing effect, which could be crucial for pandemic preparedness. Last but not least, we assessed the role of caspase-1/11 in the generation of the immune response triggered by the IQB90 adjuvanted influenza vaccine in a mouse model and found that the cellular-mediated immune response triggered by the IQB90-Flu relies, at least in part, on a mechanism involving the casp-1/11 pathway but not the humoral response elicited by this formulation
Dating Violence : Stude with Adolescents from Heredia (Costa Rica)
RESUMEN: Gran parte del comportamiento agresivo humano se da en el contexto de una relación amorosa. El colectivo adolescente no es una excepción: las investigaciones señalan una notable prevalencia de este problema, evidenciándose la necesidad de profundizar en su estudio, especialmente en Iberoamérica, dada la escasez de trabajos al respecto. Este estudio tiene como objetivos fortalecer el conocimiento sobre el comportamiento agresivo en parejas adolescentes de Costa Rica. Para ello, se toman en consideración diferentes formas de agresión, en lugar de analizar únicamente agresiones físicas o sexuales; además se estudian posibles diferencias en función del sexo. Basándose en un diseño ex post facto, se aplica un instrumento estandarizado a 468 adolescentes de Heredia (Costa Rica), que analiza cinco formas de agresión: verbal-emocional; física; sexual; relacional y amenazas. Los resultados muestran que son escasos los participantes en la investigación que no cometieron o sufrieron alguna agresión en pareja, especialmente verbales-emocionales o verbales-emocionales y sexuales, si bien la frecuencia de estas fue baja; además, se detectan algunas diferencias significativas intersexos. De los hallazgos obtenidos se concluye la existencia de dificultades en los adolescentes para afrontar, de forma constructiva, conflictos que se presentan en sus relaciones, algo que debe ser abordado de manera integral para incrementar la eficacia de los programas preventivos para jóvenes.ABSTRACT: Most of human aggressive behavior occurs in the context of a romantic relationship. Adolescents are not an exception: research show a significant prevalence of dating violence, revealing the need for further study, especially in Latin America, given the lack of research on this topic. This study aims at strengthening knowledge about aggressive behavior in adolescent dating relationships in Costa Rica, taking into account different aggressive behaviors, not only physical or sexual abuse; differences by gender are also analyzed. Based on an ex post facto design, a standardized instrument was used to measure five types of aggressive behavior (i.e., verbal-emotional, physical, sexual, relational and threats) in a sample of 468 adolescents from Heredia (Costa Rica). Results show that most participants had committed or suffered aggressions in dating relationships, especially verbal-emotional or both verbal-emotional and sexual abuse, but the mean frequency of reported aggression was low; some significant intersex differences were also found. Results obtained indicate that adolescents have difficulties to deal with conflicts in their romantic relationship; thus this problem needs to be addressed holistically in order to increase the impact of prevention programs for youth
Oseltamivir-Resistant Pandemic A/H1N1 Virus Is as Virulent as Its Wild-Type Counterpart in Mice and Ferrets
The neuraminidase inhibitor oseltamivir is currently used for treatment of patients infected with the pandemic A/H1N1 (pH1N1) influenza virus, although drug-resistant mutants can emerge rapidly and possibly be transmitted. We describe the characteristics of a pair of oseltamivir-resistant and oseltamivir-susceptible pH1N1 clinical isolates that differed by a single change (H274Y) in the neuraminidase protein. Viral fitness of pH1N1 isolates was assessed in vitro by determining replication kinetics in MDCK α2,6 cells and in vivo by performing experimental infections of BALB/c mice and ferrets. Despite slightly reduced propagation of the mutant isolate in vitro during the first 24 h, the wild-type (WT) and mutant resistant viruses induced similar maximum weight loss in mice and ferrets with an identical pyrexic response in ferrets (AUC of 233.9 and 233.2, P = 0.5156). Similarly, comparable titers were obtained for the WT and the mutant strains on days 1, 3, 6 and 9 post-infection in mouse lungs and on days 1–7 in ferret nasal washes. A more important perivascular (day 6) and pleural (days 6 and 12) inflammation was noted in the lungs of mice infected with the H274Y mutant, which correlated with increased pulmonary levels of IL-6 and KC. Such increased levels of IL-6 were also observed in lymph nodes of ferrets infected with the mutant strain. Furthermore, the H274Y mutant strain was transmitted to ferrets. In conclusion, viral fitness of the H274Y pH1N1 isolate is not substantially altered and has the potential to induce severe disease and to disseminate
Seroconversion to Seasonal Influenza Viruses after A(H1N1)pdm09 Virus Infection, Quebec, Canada
We looked for cross-reactive antibodies in 122 persons with paired serum samples collected during the 2009 pandemic of influenza virus A(H1N1)pdm09. Eight (12%) of 67 persons with A(H1N1)pdm09 infection confirmed by reverse transcription PCR and/or serology also seroconverted to the seasonal A/Brisbane/59/2007 (H1N1) virus, compared with 1 (2%) of 55 A(H1N1)pdm09-negative persons (p<0.05)
World Society for Virology first international conference: Tackling global virus epidemics
This communication summarizes the presentations given at the 1st international conference of the World Society for Virology (WSV) held virtually during 16–18 June 2021, under the theme of tackling global viral epidemics. The purpose of this biennial meeting is to foster international collaborations and address important viral epidemics in different hosts. The first day included two sessions exclusively on SARS-CoV-2 and COVID-19. The other two days included one plenary and three parallel sessions each. Last not least, 16 sessions covered 140 on-demand submitted talks. In total, 270 scientists from 49 countries attended the meeting, including 40 invited keynote speakers.Peer reviewe
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World Society for Virology first international conference: Tackling global virus epidemics.
Funder: Department of Health, Australian GovernmentThis communication summarizes the presentations given at the 1st international conference of the World Society for Virology (WSV) held virtually during 16-18 June 2021, under the theme of tackling global viral epidemics. The purpose of this biennial meeting is to foster international collaborations and address important viral epidemics in different hosts. The first day included two sessions exclusively on SARS-CoV-2 and COVID-19. The other two days included one plenary and three parallel sessions each. Last not least, 16 sessions covered 140 on-demand submitted talks. In total, 270 scientists from 49 countries attended the meeting, including 40 invited keynote speakers
Identification of Thioredoxin Glutathione Reductase Inhibitors That Kill Cestode and Trematode Parasites
Parasitic flatworms are responsible for serious infectious diseases that affect humans as well as livestock animals in vast regions of the world. Yet, the drug armamentarium available for treatment of these infections is limited: praziquantel is the single drug currently available for 200 million people infected with Schistosoma spp. and there is justified concern about emergence of drug resistance. Thioredoxin glutathione reductase (TGR) is an essential core enzyme for redox homeostasis in flatworm parasites. In this work, we searched for flatworm TGR inhibitors testing compounds belonging to various families known to inhibit thioredoxin reductase or TGR and also additional electrophilic compounds. Several furoxans and one thiadiazole potently inhibited TGRs from both classes of parasitic flatworms: cestoda (tapeworms) and trematoda (flukes), while several benzofuroxans and a quinoxaline moderately inhibited TGRs. Remarkably, five active compounds from diverse families possessed a phenylsulfonyl group, strongly suggesting that this moiety is a new pharmacophore. The most active inhibitors were further characterized and displayed slow and nearly irreversible binding to TGR. These compounds efficiently killed Echinococcus granulosus larval worms and Fasciola hepatica newly excysted juveniles in vitro at a 20 µM concentration. Our results support the concept that the redox metabolism of flatworm parasites is precarious and particularly susceptible to destabilization, show that furoxans can be used to target both flukes and tapeworms, and identified phenylsulfonyl as a new drug-hit moiety for both classes of flatworm parasites
Activity of the Oral Neuraminidase Inhibitor A-322278 against the Oseltamivir-Resistant H274Y (A/H1N1) Influenza Virus Mutant in Mice▿
The new oral neuraminidase (NA) inhibitor A-322278 was evaluated in mice infected with influenza A/H1N1 wild-type virus or the oseltamivir-resistant (H274Y mutant) virus. A-322278 decreased mortality rates and lung virus titers significantly more than oseltamivir in mice infected with the NA H274Y mutant when therapy was started 4 h before or even 48 h after infection
ISCOM-like Nanoparticles Formulated with <i>Quillaja brasiliensis</i> Saponins Are Promising Adjuvants for Seasonal Influenza Vaccines
Vaccination is the most effective public health intervention to prevent influenza infections, which are responsible for an important burden of respiratory illnesses and deaths each year. Currently, licensed influenza vaccines are mostly split inactivated, although in order to achieve higher efficacy rates, some influenza vaccines contain adjuvants. Although split-inactivated vaccines induce mostly humoral responses, tailoring mucosal and cellular immune responses is crucial for preventing influenza infections. Quillaja brasiliensis saponin-based adjuvants, including ISCOM-like nanoparticles formulated with the QB-90 saponin fraction (IQB90), have been studied in preclinical models for more than a decade and have been demonstrated to induce strong humoral and cellular immune responses towards several viral antigens. Herein, we demonstrate that a split-inactivated IQB90 adjuvanted influenza vaccine triggered a protective immune response, stronger than that induced by a commercial unadjuvanted vaccine, when applied either by the subcutaneous or the intranasal route. Moreover, we reveal that this novel adjuvant confers up to a ten-fold dose-sparing effect, which could be crucial for pandemic preparedness. Last but not least, we assessed the role of caspase-1/11 in the generation of the immune response triggered by the IQB90 adjuvanted influenza vaccine in a mouse model and found that the cellular-mediated immune response triggered by the IQB90-Flu relies, at least in part, on a mechanism involving the casp-1/11 pathway but not the humoral response elicited by this formulation