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At the liquid-gas phase transition in water, the density has a discontinuity at atmospheric pressure; however, the line of these first-order transitions defined by increasing the applied pressure terminates at the critical point1, a concept ubiquitous in statistical thermodynamics2. In correlated quantum materials, it was predicted3 and then confirmed experimentally4,5 that a critical point terminates the line of Mott metal-insulator transitions, which are also first-order with a discontinuous charge carrier density. In quantum spin systems, continuous quantum phase transitions6 have been controlled by pressure7,8, applied magnetic field9,10 and disorder11, but discontinuous quantum phase transitions have received less attention. The geometrically frustrated quantum antiferromagnet SrCu2(BO3)2 constitutes a near-exact realization of the paradigmatic Shastry-Sutherland model12-14 and displays exotic phenomena including magnetization plateaus15, low-lying bound-state excitations16, anomalous thermodynamics17 and discontinuous quantum phase transitions18,19. Here we control both the pressure and the magnetic field applied to SrCu2(BO3)2 to provide evidence of critical-point physics in a pure spin system. We use high-precision specific-heat measurements to demonstrate that, as in water, the pressure-temperature phase diagram has a first-order transition line that separates phases with different local magnetic energy densities, and that terminates at an Ising critical point. We provide a quantitative explanation of our data using recently developed finite-temperature tensor-network methods17,20-22. These results further our understanding of first-order quantum phase transitions in quantum magnetism, with potential applications in materials where anisotropic spin interactions produce the topological properties23,24 that are useful for spintronic applications.
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The dimerized quantum magnet BaCuSi_{2}O_{6} was proposed as an example of "dimensional reduction" arising near the magnetic-field-induced quantum critical point (QCP) due to perfect geometrical frustration of its interbilayer interactions. We demonstrate by high-resolution neutron spectroscopy experiments that the effective intrabilayer interactions are ferromagnetic, thereby excluding frustration. We explain the apparent dimensional reduction by establishing the presence of three magnetically inequivalent bilayers, with ratios 3â¶2â¶1, whose differing interaction parameters create an extra field-temperature scaling regime near the QCP with a nontrivial but nonuniversal exponent. We demonstrate by detailed quantum Monte Carlo simulations that the magnetic interaction parameters we deduce can account for all the measured properties of BaCuSi_{2}O_{6}, opening the way to a quantitative understanding of nonuniversal scaling in any modulated layered system.
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Interleukin-33 (IL-33) and its receptor, ST2, are implicated in bone remodeling. The lack of estrogen after menopause results in an accelerated bone loss. Here we investigated the role of ST2 in the bone loss induced by estrogen deficiency. ST2-deficient mice (ST2-/- ) and their littermates (wildtype [WT]) were ovariectomized (OVX), while ovary-intact mice were used as controls. Bone sites were analyzed by microcomputed tomography, histomorphometry, and quantitative real-time polymerase chain reaction (qPCR). Deletion of IL-33 or ST2 resulted in a similar bone loss in the femur and maxilla. Ovariectomy in WT mice caused bone loss in the same areas. The lack of ST2 in OVX mice did not alter bone remodeling in the femur but prevented bone loss in the maxilla. Consistently, ovariectomy increased the IL-33 messenger RNA (mRNA) levels in the maxilla but not in the femur. Under mechanical stimulation, ovariectomy and ST2 deletion independently increased bone remodeling induced by orthodontic tooth movement, which was also associated with a greater number of osteoclasts and a reduced number of osteoblasts in the maxillary bone. ST2-/- OVX mice, however, displayed twice as many osteoblasts as that of WT OVX mice. Ovariectomy and ST2 deletion differently altered the cytokine mRNA levels in the maxilla. Remarkably, interleukin-10 expression was decreased in both WT OVX and ST2-/- mice, and this reduction was completely restored in ST2-/- OVX mice. The results demonstrate that estrogen and IL33/ST2 independently protect against bone loss. However, the ovariectomy-induced bone loss is IL-33/ST2-dependent in the maxilla but not in the femur, indicating a bimodal and site-specific role of ST2 in bone remodeling.
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Remodelación Ósea/fisiología , Estrógenos/deficiencia , Proteína 1 Similar al Receptor de Interleucina-1/genética , Proteína 1 Similar al Receptor de Interleucina-1/metabolismo , Osteoporosis/metabolismo , Análisis de Varianza , Animales , Modelos Animales de Enfermedad , Femenino , Fémur , Técnicas de Inactivación de Genes , Interleucina-10/metabolismo , Interleucina-33/genética , Maxilar , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteoporosis/etiología , Ovariectomía/efectos adversos , ARN Mensajero/metabolismo , Semaforina-3A/metabolismo , Microtomografía por Rayos XRESUMEN
We consider the finite-temperature phase diagram of the S=1/2 frustrated Heisenberg bilayer. Although this two-dimensional system may show magnetic order only at zero temperature, we demonstrate the presence of a line of finite-temperature critical points related to the line of first-order transitions between the dimer-singlet and -triplet regimes. We show by high-precision quantum Monte Carlo simulations, which are sign-free in the fully frustrated limit, that this critical point is in the Ising universality class. At zero temperature, the continuous transition between the ordered bilayer and the dimer-singlet state terminates on the first-order line, giving a quantum critical end point, and we use tensor-network calculations to follow the first-order discontinuities in its vicinity.
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We investigate manifestations of topological order in monoaxial helimagnet Cr_{1/3}NbS_{2} by performing transport measurements on ultrathin crystals. Upon sweeping the magnetic field perpendicularly to the helical axis, crystals thicker than one helix pitch (48 nm) but much thinner than the magnetic domain size (â¼1 µm) are found to exhibit sharp and hysteretic resistance jumps. We show that these phenomena originate from transitions between topological sectors with a different number of magnetic solitons. This is confirmed by measurements on crystals thinner than 48 nm-in which the topological sector cannot change-that do not exhibit any jump or hysteresis. Our results show the ability to deterministically control the topological sector of finite-size Cr_{1/3}NbS_{2} and to detect intersector transitions by transport measurements.
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Alveolar bone loss is a result of an aggressive form of periodontal disease (PD) associated with Aggregatibacter actinomycetemcomitans (Aa) infection. PD is often observed with other systemic inflammatory conditions, including arthritis. Melanocortin peptides activate specific receptors to exert antiarthritic properties, avoiding excessing inflammation and modulating macrophage function. Recent work has indicated that melanocortin can control osteoclast development and function, but whether such protection takes place in infection-induced alveolar bone loss has not been investigated. The purpose of this study was to evaluate the role of melanocortin in Aa-induced PD. Mice were orally infected with Aa and treated with the melanocortin analog DTrp8-γMSH or vehicle daily for 30 d. Then, periodontal tissue was collected and analyzed. Aa-infected mice treated with DTrp8-γMSH presented decreased alveolar bone loss and a lower degree of neutrophil infiltration in the periodontium than vehicle-treated animals; these actions were associated with reduced periodontal levels of TNF-α, IFN-γ, and IL-17A. In vitro experiments with cells differentiated into osteoclasts showed that osteoclast formation and resorptive activity were attenuated after treatment with DTrp8-γMSH. Thus, melanocortin agonism could represent an innovative way to tame overexuberant inflammation and, at the same time, preserve bone physiology, as seen after Aa infection.-Madeira, M. F. M., Queiroz-Junior, C. M., Montero-Melendez, T., Werneck, S. M. C., Corrêa, J. D., Soriani, F. M., Garlet, G. P., Souza, D. G., Teixeira, M. M., Silva, T. A., Perretti, M. Melanocortin agonism as a viable strategy to control alveolar bone loss induced by oral infection.
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Pérdida de Hueso Alveolar/prevención & control , Melanocortinas/agonistas , Osteoclastos/microbiología , Infecciones por Pasteurellaceae/prevención & control , Enfermedades Periodontales/metabolismo , Aggregatibacter actinomycetemcomitans , Pérdida de Hueso Alveolar/etiología , Animales , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/fisiología , Macrófagos/inmunología , Ratones Endogámicos C57BL , Periodontitis/tratamiento farmacológico , Periodontitis/metabolismoRESUMEN
AIM: Leukotrienes (LTs) are pro-inflammatory lipid mediators formed by the enzyme 5-lipoxygenase (5-LO). The involvement of 5-LO metabolites in periodontal disease (PD) is not well defined. This study aimed to assess the role of 5-LO in experimental PD induced by Aggregatibacter actinomycetemcomitans (Aa). MATERIAL AND METHODS: In vivo experiments were carried out using SV129 wild-type (WT) and 5-LO-deficient (5lo-/- ) mice inoculated with Aa. Osteoclasts were stimulated in vitro with AaLPS in the presence or not of selective inhibitors of the 5-LO pathway, or LTB4 or platelet-activating factor (PAF), as PAF has already been shown to increase osteoclast activity. RESULTS: In 5lo-/- mice, there were no loss of alveolar bone and less TRAP-positive osteoclasts in periodontal tissues, after Aa inoculation, despite local production of TNF-α and IL-6. The differentiation and activity of osteoclasts stimulated with AaLPS were diminished in the presence of BLT1 antagonist or 5-LO inhibitor, but not in the presence of cysteinyl leukotriene receptor antagonist. The osteoclast differentiation induced by PAF was impaired by the BLT1 antagonism. CONCLUSION: In conclusion, LTB4 but not CysLTs is important for Aa-induced alveolar bone loss. Overall, LTB4 affects osteoclast differentiation and activity and is a key intermediate of PAF-induced osteoclastogenesis.
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Aggregatibacter actinomycetemcomitans/patogenicidad , Pérdida de Hueso Alveolar/enzimología , Pérdida de Hueso Alveolar/microbiología , Araquidonato 5-Lipooxigenasa/farmacología , Animales , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Hidroxiurea/análogos & derivados , Hidroxiurea/farmacología , Interleucina-6/metabolismo , Ratones , Osteoclastos/efectos de los fármacos , Reacción en Cadena en Tiempo Real de la Polimerasa , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
The relevance of IL-33 and its receptor ST2 for bone remodeling is not well-defined. Our aim was to assess the role and underlying mechanisms of IL-33/ST2 in mechanically induced bone remodeling. BALB/c (wild type) and ST2 deficient (St2(-/-)) mice were subjected to mechanical loading in alveolar bone. Microtomography, histology, and real-time quantitative PCR were performed to analyze bone parameters, apoptosis and bone cell counts, and expression of bone remodeling markers, respectively. MC3T3-E1 osteoblastic cells and bone marrow cells were used to verify if mechanical force triggered IL-33 and ST2 expression as well as the effects of IL-33 on osteoclast differentiation and activity. Mechanical loading increased the expression of IL-33 and ST2 in alveolar bone in vivo and in osteoblastic cells in vitro. St2(-/-) mice had increased mechanical loading-induced bone resorption, number of osteoclasts, and expression of proresorptive markers. In contrast, St2(-/-) mice exhibited reduced numbers of osteoblasts and apoptotic cells in periodontium and diminished expression of osteoblast signaling molecules. In vitro, IL-33 treatment inhibited osteoclast differentiation and activity even in the presence of receptor activator of NF-κB ligand. IL-33 also increased the expression of pro-apoptotic molecules, including Bcl-2-associated X protein (BAX), cell-surface Fas receptor (FAS), FASL, FAS-associated death domain, tumor necrosis factor-related apoptosis-inducing ligand, and BH3 interacting-domain death (BID). Overall, these findings suggest that IL-33/ST2 have anti-osteoclastogenic effects and reduce osteoclast formation and activity by inducing their apoptosis.
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Apoptosis/fisiología , Remodelación Ósea/fisiología , Interleucina-33/fisiología , Osteoclastos/fisiología , Receptores de Interleucina/fisiología , Animales , Biomarcadores/metabolismo , Densidad Ósea/fisiología , Resorción Ósea/fisiopatología , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Proteína 1 Similar al Receptor de Interleucina-1 , Interleucina-33/biosíntesis , Interleucina-33/farmacología , Ratones Endogámicos BALB C , Ratones Noqueados , Osteoclastos/citología , Osteoclastos/efectos de los fármacos , Osteoclastos/metabolismo , Periodoncio/metabolismo , Periodoncio/patología , Receptores de Interleucina/biosíntesis , Receptores de Interleucina/deficiencia , Estrés Mecánico , Soporte de PesoRESUMEN
Because there is clinical evidence for an association between periodontal disease and rheumatoid arthritis, it is important to develop suitable experimental models to explore pathogenic mechanisms and therapeutic opportunities. The K/BxN serum model of inflammatory arthritis was applied using distinct protocols, and modulation of joint disruption afforded by dexamethasone and calcitonin was established in comparison to the melanocortin (MC) receptor agonist DTrp(8)-γ-melanocyte stimulating hormone (MSH; DTrp). Wild-type and MC receptor type 3 (MC3)-null mice of different ages were also used. There was significant association between severity of joint disease, induced with distinct protocols and volumes of the arthritogenic K/BxN serum, and periodontal bone damage. Therapeutic treatment with 10 µg dexamethasone, 30 ng elcatonin, and 20 µg DTrp per mouse revealed unique and distinctive pharmacological properties, with only DTrp protecting both joint and periodontal tissue. Further analyses in nonarthritic animals revealed higher susceptibility to periodontal bone loss in Mc3r(-/-) compared with wild-type mice, with significant exacerbation at 14 weeks of age. These data reveal novel protective properties of endogenous MC3 on periodontal status in health and disease and indicate that MC3 activation could lead to the development of a new genus of anti-arthritic bone-sparing therapeutics.
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Artritis Experimental/metabolismo , Artritis Reumatoide/metabolismo , Enfermedades Periodontales/metabolismo , Receptor de Melanocortina Tipo 3/metabolismo , Animales , Artritis Experimental/complicaciones , Artritis Reumatoide/complicaciones , Modelos Animales de Enfermedad , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Enfermedades Periodontales/complicacionesRESUMEN
Irinotecan is a useful chemotherapeutic for the treatment of various cancers. Irinotecan treatment is associated with mucositis, which clearly limits the use of the drug. Mechanisms that account for mucositis are only partially known. This study assessed mechanisms and the role of inflammasome activation in irinotecan-induced mucositis. Mucositis in mice was induced by irinotecan injection in C57BL/6 wild-type, gp91phox(-/-), il-18(-/-), casp-1(-/-), and asc(-/-) mice once a day for 4 consecutive days. In some experiments, mice received apocynin to inhibit NADPH oxidase (NOX), IL-1 receptor antagonist, or IL-18 binding protein to prevent activation of IL-1 and IL-18 receptors, respectively. Mice were euthanized 7 days after the beginning of irinotecan treatment, and small intestines were collected for analysis. Irinotecan treatment resulted in increased IL-1ß and IL-18 production in ileum and NOX-2-dependent oxidative stress. gp91phox(-/-) and apocynin-treated mice had diminished oxidative stress and less severe mucositis. Furthermore, treatment with apocynin decreased caspase-1 activation and IL-1ß and IL-18 production in the ileum. asc(-/-) and casp-1(-/-) mice also had less intestinal injury and decreased IL-1ß and IL-18 production. Finally, both the absence of IL-18 and IL-1ß resulted in reduced inflammatory response and attenuated intestinal injury. NOX-2-derived oxidative stress mediates inflammasome activation and inflammasome-dependent production of IL-1ß and IL-18, which mediate tissue injury during irinotecan-induced mucositis in mice.
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Inflamasomas/metabolismo , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , Mucositis/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Animales , Camptotecina/efectos adversos , Camptotecina/análogos & derivados , Caspasa 1/metabolismo , Íleon/metabolismo , Íleon/patología , Irinotecán , Masculino , Glicoproteínas de Membrana/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Mucositis/inducido químicamente , NADPH Oxidasa 2 , NADPH Oxidasas/metabolismo , Estrés OxidativoRESUMEN
We report on the real space profile of spin polarons in the quasi-two-dimensional frustrated dimer spin system SrCu(2)(BO(3))(2) doped with 0.16% of Zn. The (11)B nuclear magnetic resonance spectrum exhibits 15 additional boron sites near nonmagnetic Zn impurities. With the help of exact diagonalizations of finite clusters, we have deduced from the boron spectrum, the distribution of local magnetizations at the Cu sites with fine spatial resolution, providing direct evidence for an extended spin polaron. The results are confronted with those of other experiments performed on doped and undoped samples of SrCu(2)(BO(3))(2).
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We investigate by angle-resolved photoemission the electronic structure of in situ grown tetragonal CuO, a synthetic quasi-two-dimensional edge-sharing cuprate. We show that, in spite of the very different nature of the copper oxide layers, with twice as many Cu in the CuO layers of tetragonal CuO as compared to the CuO(2) layers of the high-T(c) cuprates, the low-energy electronic excitations are surprisingly similar, with a Zhang-Rice singlet dispersing on weakly coupled cupratelike sublattices. This system should thus be considered as a member of the high-T(c) cuprate family, with, however, interesting differences due to the intralayer coupling between the cupratelike sublattices.
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Human-centred design (HCD) is an approach to problem-solving that prioritises understanding and meeting the needs of the end-users. Researchers and designers practice empathic listening as users share their perspectives, thereby enabling a variety of stakeholders to cocreate effective solutions. While a valuable and, in theory, straightforward process, HCD in practice can be chaotic: Practitioners often struggle to navigate an excess of (often conflicting) ideas and to strike a balance between problem-understanding and problem-solving. In this practice paper, we outline our own experiences with HCD, which ultimately resulted in the development of a successful video-based intervention to bolster vaccine confidence in the Philippines. We highlight the use of 'radical circles' to overcome roadblocks and navigate tensions. Radical circles entail groups of individuals with divergent opinions and identities engaging in critical analysis of a given idea, actively challenging standard ways of thinking, and ultimately, generating solutions. Employing radical circles enabled us to innovate and adapt to new perspectives that emerged along the non-linear HCD pathway. Our incorporation of radical circles into HCD methodology demonstrates its potential as a powerful complementary step in the meaning-making process. In our view, radical circles could enrich HCD processes and provide a solution to design overcrowding, leading to meaningful, transformative and successful interventions.
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Promoción de la Salud , Humanos , Filipinas , Promoción de la Salud/métodos , Vacunas , Solución de ProblemasRESUMEN
We report on NMR and torque measurements on the frustrated quasi-two-dimensional spin-dimer system SrCu(2)(BO(3))(2) in magnetic fields up to 34 T that reveal a sequence of magnetization plateaus at 1/8, 2/15, 1/6, and 1/4 of the saturation and two incommensurate phases below and above the 1/6 plateau. The magnetic structures determined by NMR involve a stripe order of triplets in all plateaus, suggesting that the incommensurate phases originate from proliferation of domain walls. We propose that the magnetization process of SrCu(2)(BO(3))(2) is best described as an incomplete devil's staircase.
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The magnetization process of the orthogonal-dimer antiferromagnet SrCu2(BO3)2 is investigated in high magnetic fields of up to 118 T. A 1/2 plateau is clearly observed in the field range 84 to 108 T in addition to 1/8, 1/4, and 1/3 plateaus at lower fields. Using a combination of state-of-the-art numerical simulations, the main features of the high-field magnetization, a 1/2 plateau of width 24 T, a 1/3 plateau of width 34 T, and no 2/5 plateau, are shown to agree quantitatively with the Shastry-Sutherland model if the ratio of inter- to intradimer exchange interactions J'/J=0.63. It is further predicted that the intermediate phase between the 1/3 and 1/2 plateaus is not uniform but consists of a 1/3 supersolid followed by a 2/5 supersolid and possibly a domain-wall phase, with a reentrance into the 1/3 supersolid above the 1/2 plateau.
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Under magnetic fields, quantum magnets often undergo exotic phase transitions with various kinds of order. The discovery of a sequence of fractional magnetization plateaus in the Shastry-Sutherland compound SrCu2(BO3)2 has played a central role in the high-field research on quantum materials, but so far this system could only be probed up to half the saturation value of the magnetization. Here, we report the first experimental and theoretical investigation of this compound up to the saturation magnetic field of 140 T and beyond. Using ultrasound and magnetostriction techniques combined with extensive tensor-network calculations (iPEPS), several spin-supersolid phases are revealed between the 1/2 plateau and saturation (1/1 plateau). Quite remarkably, the sound velocity of the 1/2 plateau exhibits a drastic decrease of -50%, related to the tetragonal-to-orthorhombic instability of the checkerboard-type magnon crystal. The unveiled nature of this paradigmatic quantum system is a new milestone for exploring exotic quantum states of matter emerging in extreme conditions.
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Campos Magnéticos , Imanes , Fenómenos Químicos , Fenómenos Físicos , RegistrosRESUMEN
INTRODUCTION: The success of global health interventions heavily relies on reaching populations in a way that aligns with their priorities and needs. This warrants novel approaches to determine the design of meaningful interventions and targeted delivery pathways. To date, global health scholarship and practice have largely underused approaches already established in fields that emphasize customer satisfaction, such as quality management or consumer psychology. METHODS: In our study, we apply Kano methodology-originally designed to understand how product attributes nonlinearly influence customer satisfaction-to inform design decisions regarding a video-based vaccine intervention in the Philippines. Between September 2021 and April 2022, we administered a Kano questionnaire to 205 caregivers of small children. Data were analyzed following routine Kano approaches, supplemented by cultural consensus analysis (CCA), which is an approach used largely in anthropology to identify distinct cultural groups and competencies. RESULTS: Applying Kano and CCA methodologies allowed us to make informed design decisions in terms of optimizing accessibility and credibility of an intervention that ultimately proved successful in bolstering vaccine intentions. Results guided us to include national and international logos, to appreciate the value of summarizing key messages, and to recognize the importance of fact- or story-based communication as attributes that influenced respondent satisfaction one-dimensionally. We found that involving trusted messengers and including text-based information were required to avoid dissatisfaction. Interacting with someone after viewing the product and creating opportunities to share the promotional material via social media were attractive attributes whose presence would increase satisfaction but would not spark severe dissatisfaction if omitted. Other attributes (short duration, video- or animation-based intervention, delivering the intervention at health centers or in group settings) played a limited role in respondent satisfaction. CONCLUSIONS: Global health research and practice can benefit from applying approaches established in other fields when making evidence-based prioritization decisions to tailor interventions.
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Satisfacción Personal , Vacunas , Niño , Humanos , Filipinas , Nigeria , Comportamiento del ConsumidorRESUMEN
BACKGROUND: The public's confidence in vaccinations has eroded, and anti-vaccination movements have gained traction around the world, including in the Philippines. 'Salubong', a Filipino term, refers to welcoming someone back into one's life and elicits ideas about friendship and family relationships. We extended this concept to vaccines in efforts to design an intervention that would re-welcome vaccines into homes. METHODS: Using human-centred design, we developed and refined a story-based intervention that engages Filipino families, community leaders and community health workers. We conducted a randomised controlled trial among 719 caregivers of small children to test the developed intervention against a control video. We assessed the binary improvement (improvement vs no improvement) and the amount of improvement in vaccine attitudes and intentions after intervention exposure. RESULTS: Although the intervention group began with marginally higher baseline vaccine attitude scores, we found that 62% of the intervention group improved their vaccine attitude scores versus 37% of the control group (Fisher's exact, p<0.001). Among individuals whose scores improved after watching the assigned video, the intervention group saw higher mean attitude score improvements on the 5-point scale (Cohen's d=0.32 with 95% CI 0.10 to 0.54, two-sided t-test, p<0.01). We observed similar patterns among participants who stated that they had previously delayed or refused a vaccine for their child: 67% of 74 in the intervention group improved their vaccine attitude scores versus 42% of 54 in the control group (Fisher's exact, p<0.001). Among the subset of these individuals whose scores improved after watching the assigned video, the intervention group saw higher mean attitude score improvements on the 5-point scale that were marginally significant (Cohen's d=0.35 with 95% CI -0.01 to 0.70, two-sided t-test, p=0.06). CONCLUSIONS: Our results provide solid evidence for the potential of co-designed vaccine confidence campaigns and regulations.
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Vacunas , Niño , Humanos , Filipinas , Vacunación , Agentes Comunitarios de SaludRESUMEN
INTRODUCTION: Targeted vaccination promotion efforts aimed at building vaccine confidence require an in-depth understanding of how and by whom decisions about vaccinating children are made. While several studies have highlighted how parents interact with other stakeholders when discussing childhood vaccination, less is known about the way in which vaccination uptake is negotiated within households. METHODS: We conducted 44 in-depth interviews with caregivers of children under five in the Philippines who had delayed or refused vaccination. Interviews were conducted between August 2020 and March 2021 and were audio-recorded, transcribed verbatim and translated into English. Notions of intra-household vaccination bargaining emerged early during systematic debriefings and were probed more pointedly throughout data collection. RESULTS: Parents as well as paternal and maternal families proved to be dominant stakeholders in intra-household bargaining for childhood vaccination. Although bargaining among these stakeholders was based on engrained, gender-based power imbalances, disadvantaged stakeholders could draw on a range of interrelated sources of bargaining power to nevertheless shape decision-making. Sources of bargaining power included, in descending order of their relevance for vaccination, (1) physical presence at the household (at the time of vaccination decision-making), (2) interest in the topic of vaccination and conviction of one's own position, (3) previous vaccination and caregiving experience, and (4) access to household resources (including finances). The degree to which each household member could draw on these sources of bargaining power varied considerably over time and across households. CONCLUSION: Our findings highlight how bargaining due to intra-household disagreement coins decisions regarding childhood vaccination. Considering the risks for public health associated with vaccine hesitancy globally, we advocate for acknowledging intra-household dynamics in research and practice, such as by purposefully targeting household members with decision-making capacity in vaccination promotion efforts, aligning promotion efforts with available bargaining capacity or further empowering those convinced of vaccination.
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Composición Familiar , Vacunación , Niño , Humanos , Negociación , Padres , FilipinasRESUMEN
BACKGROUND: Obesity leads to chronic low-grade inflammation, promoting detrimental effects on bone. The consumption of virgin coconut oil (VCO) is associated with benefits related to meta-inflammation. We evaluated the effect of VCO supplementation on osteopenia promoted by diet-induced obesity in mice. METHODS: Male BALB/c mice were fed a control (C) or highly refined carbohydrate-containing (HC) diet for eight weeks. After that, the HC diet group was supplemented with three doses of VCO for four weeks. RESULTS: The HC diet increased the adiposity and leptin levels associated with augmented systemic inflammatory cells improved with VCO supplementation. The HC diet reduced the trabecular bone in the tibia, lumbar vertebrae, distal and proximal femur, as well as the bone mineral density of the femur and alveolar bone. The VCO supplementation reverted bone osteopenia by increasing the trabecular bone in different sites and improving femur and alveolar bone microarchitecture. Although the reduced number of osteoblasts in the alveolar bone of the HC diet group was not significantly enhanced by VCO supplementation, the reduced Alp expression in the HC diet group was enhanced in the VCO group. These beneficial effects were associated with lowering the Rankl/Opg ratio. CONCLUSION: VCO supplementation might be an effective strategy to attenuate bone osteopenic effects induced by obesity.