175 research outputs found

    Zinc-Assisted Microscale Granules Made of the SARS-CoV-2 Spike Protein Trigger Neutralizing, Antivirus Antibody Responses

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    Protein secretory granules; SARS-CoV-2; AntibodiesGránulos secretores de proteínas; SARS-CoV-2; AnticuerposGrànuls secretors de proteïnes; SARS-CoV-2; AnticossosThe development of new and more efficient vaccination approaches is a constant need, due to the pressure of historical and emerging infectious diseases and the limited efficacy and universality of the current vaccination technologies. Peptides and recombinant proteins have been explored for decades as subunit vaccines for bacterial and viral infections, presented either as soluble protein species or as virus-like assemblies. Recently, synthetic secretory protein-only microscale granules have been developed as dynamic depots for sustained protein release. They are based on the reversible coordination between ionic Zn and histidine residues, which promotes a fast formation of granular particles in vitro out of soluble protein and a slow release of such building block protein in vivo through the physiological chelation of the metal. Such an endocrine-like platform represents a new drug delivery system fully validated in oncology by which soluble and functional protein drugs are progressively released from the granules and made available for antitumor activities upon subcutaneous administration. By exploring such an approach for immunization here, microparticles made of a recombinant form of the receptor binding domain (RBD) of SARS-CoV-2 were tested as an antigen delivery system for induction of antibody responses against the virus upon administration of the material in the absence of added adjuvants. Also, the comparison between protein materials produced in bacterial, mammalian, or insect cell factories has demonstrated a moderate impact of protein glycosylation on the final immunological performance of the system. Therefore, we propose the consideration of synthetic protein secretory granules as a new sustainable immunization platform based on fully manageable, self-organized, and self-formulated immunogens, aimed at reducing the dosage, costs, and complexity of vaccination regimens.The authors appreciate the financial support received from AGAUR (2020PANDE00003 and 2021SGR00092 to A.V.), from CIBER-Consorcio Centro de Investigación Biomédica en Red- (CB06/01/0014), Instituto de Salud Carlos III, Ministerio de Ciencia e Innovación, through intramural projects (NANOSARS to E.P. and NANOREMOTE to E.V.). We also appreciate the support from AEI for the development of multimeric recombinant drugs (PID2019-105416RB-I00/AEI/10.13039/501100011033 and PDC2022-133858-I00 to E.V., PID2019-107298RB-C22 to N.F.-M., PID2020-116174RB-I00 to A.V. and PID2022-1368450 OB-10/AEI/10.13039/501100011033 to A.V. and E.V.). M.T.P.F. received a FAPESP fellowship (No. 2021/08528-0) and L.C.S.F. received a FAPESP research grant (No. 2020/05204-7). A.V. received an ICREA ACADEMIA award

    Visualizing group II intron dynamics between the first and second steps of splicing

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    Group II introns are ubiquitous self-splicing ribozymes and retrotransposable elements evolutionarily and chemically related to the eukaryotic spliceosome, with potential applications as gene-editing tools. Recent biochemical and structural data have captured the intron in multiple conformations at different stages of catalysis. Here, we employ enzymatic assays, X-ray crystallography, and molecular simulations to resolve the spatiotemporal location and function of conformational changes occurring between the first and the second step of splicing. We show that the first residue of the highly-conserved catalytic triad is protonated upon 5’-splice-site scission, promoting a reversible structural rearrangement of the active site (toggling). Protonation and active site dynamics induced by the first step of splicing facilitate the progression to the second step. Our insights into the mechanism of group II intron splicing parallels functional data on the spliceosome, thus reinforcing the notion that these evolutionarily-related molecular machines share the same enzymatic strategy

    Differentiated neuroprogenitor cells incubated with human or canine adenovirus, or lentiviral vectors have distinct transcriptome profiles

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    Several studies have demonstrated the potential for vector-mediated gene transfer to the brain. Helper-dependent (HD) human (HAd) and canine (CAV-2) adenovirus, and VSV-G-pseudotyped self-inactivating HIV-1 vectors (LV) effectively transduce human brain cells and their toxicity has been partly analysed. However, their effect on the brain homeostasis is far from fully defined, especially because of the complexity of the central nervous system (CNS). With the goal of dissecting the toxicogenomic signatures of the three vectors for human neurons, we transduced a bona fide human neuronal system with HD-HAd, HD-CAV-2 and LV. We analysed the transcriptional response of more than 47,000 transcripts using gene chips. Chip data showed that HD-CAV-2 and LV vectors activated the innate arm of the immune response, including Toll-like receptors and hyaluronan circuits. LV vector also induced an IFN response. Moreover, HD-CAV-2 and LV vectors affected DNA damage pathways - but in opposite directions - suggesting a differential response of the p53 and ATM pathways to the vector genomes. As a general response to the vectors, human neurons activated pro-survival genes and neuron morphogenesis, presumably with the goal of re-establishing homeostasis. These data are complementary to in vivo studies on brain vector toxicity and allow a better understanding of the impact of viral vectors on human neurons, and mechanistic approaches to improve the therapeutic impact of brain-directed gene transfer

    Write, draw, show, and tell: a child-centred dual methodology to explore perceptions of out-of-school physical activity

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    Background Research to increase children’s physical activity and inform intervention design has, to date, largely underrepresented children’s voices. Further, research has been limited to singular qualitative methods that overlook children’s varied linguistic ability and interaction preference. The aim of this study was to use a novel combination of qualitative techniques to explore children’s current views, experiences and perceptions of out-of-school physical activity as well as offering formative opinion about future intervention design. Methods Write, draw, show and tell (WDST) groups were conducted with 35 children aged 10–11 years from 7 primary schools. Data were analysed through a deductive and inductive process, firstly using the Youth Physical Activity Promotion Model as a thematic framework, and then inductively to enable emergent themes to be further explored. Pen profiles were constructed representing key emergent themes. Results The WDST combination of qualitative techniques generated complimentary interconnected data which both confirmed and uncovered new insights into factors relevant to children’s out-of-school physical activity. Physical activity was most frequently associated with organised sports. Fun, enjoyment, competence, and physical activity provision were all important predictors of children’s out-of-school physical activity. Paradoxically, parents served as both significant enablers (i.e. encouragement) and barriers (i.e. restricting participation) to physical activity participation. Some of these key findings would have otherwise remained hidden when compared to more traditional singular methods based approaches. Conclusions Parents are in a unique position to promote health promoting behaviours serving as role models, physical activity gatekeepers and choice architects. Given the strong socialising effect parents have on children’s physical activity, family-based physical activity intervention may offer a promising alternative compared to traditional school-based approaches. Parents' qualitative input is important to supplement children’s voices and inform future family-based intervention design. The WDST method developed here is an inclusive, interactive and child-centred methodology which facilitates the exploration of a wide range of topics and enhances data credibility

    Walking school buses as a form of active transportation for children : A review of the evidence

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    ABSTRACT BACKGROUND: Walking School Buses (WSBs) offer a potentially healthier way for children to get to school whilst reducing traffic congestion. A number of pressing societal challenges make it timely to evaluate evidence of their value. METHODS: Studies that focused solely on WSBs were identified through online and manual literature searches. Twelve WSB studies involving a total of 9173 children were reviewed. Study aims, designs, methods, outcomes, and barriers and facilitators were examined. RESULTS: WSBs were found to be associated with increased prevalence of walking to school and general activity levels though not always significantly. Time constraints emerged as barriers to WSBs, impacting on recruitment of volunteers and children to the WSBs. Facilitators of WSBs included children enjoying socializing and interacting with the environment. CONCLUSIONS: Preliminary evidence of the health value of WSBs was demonstrated, along with recommendations for the design of future studies. By tackling barriers of time constraints, volunteer recruitment and parents’ safety concerns whilst at the same time, increasing convenience and time savings for families, future WSBs are likely to be more sustainable and taken up by more schools. Implications for future innovation in school health were identified

    Effects of a school-based intervention on active commuting to school and health-related fitness

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    Background: Active commuting to school has declined over time, and interventions are needed to reverse this trend. The main objective was to investigate the effects of a school-based intervention on active commuting to school and health-related fitness in school-age children of Southern Spain. Methods: A total of 494 children aged 8 to 11 years were invited to participate in the study. The schools were non-randomly allocated (i.e., school level allocation) into the experimental group (EG) or the control group (CG). The EG received an intervention program for 6 months (a monthly activity) focused on increasing the level of active commuting to school and mainly targeting children’s perceptions and attitudes. Active commuting to school and health-related fitness (i.e., cardiorespiratory fitness, muscular fitness and speed-agility), were measured at baseline and at the end of the intervention. Children with valid data on commuting to school at baseline and follow-up, sex, age and distance from home to school were included in the final analysis (n = 251). Data was analyzed through a factorial ANOVA and the Bonferroni post-hoc test. Results: At follow up, the EG had higher rates of cycling to school than CG for boys only (p = 0.04), but not for walking to school for boys or girls. The EG avoided increases in the rates of passive commuting at follow up, which increased in the CG among girls for car (MD = 1.77; SE = 0.714; p = 0.010) and bus (MD = 1.77; SE = 0.714; p = 0.010) modes. Moreover, we observed significant interactions and main effects between independent variables (study group, sex and assessment time point) on health-related fitness (p < 0.05) over the 6-month period between groups, with higher values in the control group (mainly in boys). Conclusion: A school-based intervention focused on increasing active commuting to school was associated with increases in rates of cycling to school among boys, but not for walking to school or health-related fitness. However, the school-based intervention avoided increases in rates of passive commuting in the experimental group, which were significantly increased in girls of the control group

    Feasibility of an incentive scheme to promote active travel to school: a pilot cluster randomised trial

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    Abstract Background In Great Britain, 19% of trips to primary school within 1 mile, and 62% within 1–2 miles, are by car. Active travel to school (ATS) offers a potential source of moderate-to-vigorous physical activity (MVPA). This study tested the feasibility of an intervention to promote ATS in 9–10 year olds and associated trial procedures. Methods A parallel cluster randomised pilot trial was conducted over 9 weeks in two schools from a low-income area in northeast England. Measures included daily parental ATS reports (optionally by SMS) and child ATS reports, as well as accelerometry (ActiGraph GT3X+). At baseline, all children were asked to wear the accelerometer for the same week; in the post-randomisation phase, small subsamples were monitored each week. In the 2 weeks when a child wore the accelerometer, parents also reported the start and finish times of the journey to school. The intervention consisted of a lottery-based incentive scheme; every ATS day reported by the parent, whether by paper or SMS, corresponded to one ticket entered into a weekly £5 voucher draw. Before each draw session, the researcher prepared the tickets and placed them into an opaque bag, from which one was randomly picked by the teacher at the draw session. Results Four schools replied positively (3.3%, N = 123) and 29 participants were recruited in the two schools selected (33.0%, N = 88). Participant retention was 93.1%. Most materials were returned on time: accelerometers (81.9%), parental reports (82.1%) and child reports (97.9%). Draw sessions lasted on average 15.9 min (IQR 10–20) and overall session attendance was 94.5%. Parent-child report agreement regarding ATS was moderate (k = 0.53, CI 95% 0.45; 0.60). Differences in minutes of accelerometer-assessed MVPA between parent-reported ATS and non-ATS trips were assessed during two timeframes: during the journey to school based on the times reported by the parent (U = 390.5, p < 0.05, 2.46 (n = 99) vs 0.76 (n = 13)) and in the hour before classes (U = 665.5, p < 0.05, 4.99 (n = 104) vs 2.55 (n = 19)). Differences in MVPA minutes between child-reported ATS and non-ATS trips were also significant for each of the timeframes considered (U = 596.5, p < 0.05, 2.40 (n = 128) vs 0.81 (n = 15) and U = 955.0, p < 0.05, 4.99 (n = 146) vs 2.59 (n = 20), respectively). Conclusions Data suggest the feasibility of an ATS incentive scheme and of most trial procedures. School recruitment stood out as requiring further piloting. Trial registration ClinicalTrials.gov: NCT02282631 . Registered 5th September 2014

    Mode shifting in school travel mode: examining the prevalence and correlates of active school transport in Ontario, Canada

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    <p>Abstract</p> <p>Background</p> <p>Studies examining the correlates of school transport commonly fail to make the distinction between morning and afternoon school trips. The purpose of this study was to examine the prevalence and correlates of mode shift from passive in the morning to active in the afternoon among elementary and secondary school students in Ontario, Canada.</p> <p>Methods</p> <p>Data were derived from the 2009 cycle of the Ontario Student Drug Use and Health Survey (OSDUHS). 3,633 students in grades 7 through 12 completed self-administered questionnaires. Socio-demographic, behavioural, psychological, and environmental predictors of active school transport (AST) were assessed using logistic regression.</p> <p>Results</p> <p>Overall, 47% and 38% of elementary school students reported AST to and from school, respectively. The corresponding figures were 23% and 32% for secondary school students. The prevalence of AST varied temporarily and spatially. There was a higher prevalence of walking/biking found for elementary school students than for secondary school students, and there was an approximate 10% increase in AST in the afternoon. Different correlates of active school transport were also found across elementary and secondary school students. For all ages, students living in urban areas, with a shorter travel time between home and school, and having some input to the decision making process, were more likely to walk to and from school.</p> <p>Conclusions</p> <p>Future research examining AST should continue to make the analytic distinction between the morning and afternoon trip, and control for the moderating effect of age and geography in predicting mode choice. In terms of practice, these variations highlight the need for school-specific travel plans rather than 'one size fits all' interventions in promoting active school transport.</p

    Physical Activity Patterns of the Spanish Population Are Mostly Determined by Sex and Age: Findings in the ANIBES Study

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    Background Representative data for the Spanish population regarding physical activity (PA) behaviors are scarce and seldom comparable due to methodological inconsistencies. Aim Our objectives were to describe the PA behavior by means of the standardized self-reported International Physical Activity Questionnaire (IPAQ) and to know the proportion of the Spanish population meeting and not meeting international PA recommendations. Material and Methods PA was assessed using the IPAQ in a representative sample of 2285 individuals (males, 50.4%) aged 9–75 years and living in municipalities of at least 2,000 inhabitants. Data were analyzed according to: age groups 9–12, 13–17, 18–64, and 65–75 years; sex; geographical distribution; locality size and educational levels. Results Mean total PA was 868.8±660.9 min/wk, mean vigorous PA 146.4±254.1 min/wk, and mean moderate PA 398.1±408.0 min/wk, showing significant differences between sexes (p<0.05). Children performed higher moderate-vigorous PA than adolescents and seniors (p<0.05), and adults than adolescents and seniors (p<0.05). Compared to recommendations, 36.2%of adults performed <150 min/week of moderate PA, 65.4% <75 min/week of vigorous PA and 27.0%did not perform any PA at all, presenting significant differences between sexes (p<0.05). A total of 55.4%of children and adolescents performed less than 420 min/week of MVPA, being higher in the later (62.6%) than in the former (48.4%). Highest non-compliance was observed in adolescent females (86.5%). Conclusion Sex and age are the main influencing factors on PA in the Spanish population. Males engage in more vigorous and light PA overall, whereas females perform more moderate PA. PA behavior differs between age groups and no clear lineal increase with age could be observed. Twenty-seven percent of adults and 55.4% of children and adolescents do not meet international PA recommendations. Identified target groups should be addressed to increase PA in the Spanish populationCoca-Cola Iberia through Spanish Nutrition Foundation (FEN)Coca-Cola Iberi
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