16 research outputs found

    Late-acting dominant lethal genetic systems and mosquito control

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    BACKGROUND: Reduction or elimination of vector populations will tend to reduce or eliminate transmission of vector-borne diseases. One potential method for environmentally-friendly, species-specific population control is the Sterile Insect Technique (SIT). SIT has not been widely used against insect disease vectors such as mosquitoes, in part because of various practical difficulties in rearing, sterilization and distribution. Additionally, vector populations with strong density-dependent effects will tend to be resistant to SIT-based control as the population-reducing effect of induced sterility will tend to be offset by reduced density-dependent mortality. RESULTS: We investigated by mathematical modeling the effect of manipulating the stage of development at which death occurs (lethal phase) in an SIT program against a density-dependence-limited insect population. We found late-acting lethality to be considerably more effective than early-acting lethality. No such strains of a vector insect have been described, so as a proof-of-principle we constructed a strain of the principal vector of the dengue and yellow fever viruses, Aedes (Stegomyia) aegypti, with the necessary properties of dominant, repressible, highly penetrant, late-acting lethality. CONCLUSION: Conventional SIT induces early-acting (embryonic) lethality, but genetic methods potentially allow the lethal phase to be tailored to the program. For insects with strong density-dependence, we show that lethality after the density-dependent phase would be a considerable improvement over conventional methods. For density-dependent parameters estimated from field data for Aedes aegypti, the critical release ratio for population elimination is modeled to be 27% to 540% greater for early-acting rather than late-acting lethality. Our success in developing a mosquito strain with the key features that the modeling indicated were desirable demonstrates the feasibility of this approach for improved SIT for disease control

    UK women smokers' experiences of an age-progression smoking cessation intervention: Thematic analysis of accounts

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    Objectives Appearance-related interventions to promote healthy behaviour have been found effective to communicate health risks. The current study aimed to explore women smokers' experiences of age-progression software showing the effects of smoking on the face. Methods A qualitative design was implemented, utilizing both individual interviews and focus groups within a critical realist framework. Fifteen, 19–52 year-old women smokers were administered an age-progression intervention. All participants responded to the intervention, engaged in semi-structured interviews, and were invited back to attend one of three focus groups. Data were analysed using inductive thematic analysis. Results Four main themes were identified: Health versus Appearance, Shock Reaction, Perceived Susceptibility, and Intention to Quit. Participants found the intervention useful, voicing need for a comprehensive approach that includes both appearance and health. Despite increases in appearance-based apps which could diminish impact, women's accounts of shock induced by the aged smoking-morphed images were similar to previous work conducted more than ten years previously. Conclusions The study provides novel insights in how women smokers currently perceive, and react to, an age-progression intervention for smoking cessation. Innovation Findings emphasise the implementation of this intervention type accompanied by health information in a range of patient settings

    Expression of p16 Within Myenteric Neurons of the Aged Colon: A Potential Marker of Declining Function.

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    Human colonic neuromuscular functions decline among the elderly. The aim was to explore the involvement of senescence. A preliminary PCR study looked for age-dependent differences in expression of CDKN1A (encoding the senescence-related p21 protein) and CDKN2A (encoding p16 and p14) in human ascending and descending colon (without mucosa) from 39 (approximately 50: 50 male: female) adult (aged 27-60 years) and elderly donors (70-89 years). Other genes from different aging pathways (e.g., inflammation, oxidative stress, autophagy) and cell-types (e.g., neurons, neuron axonal transport) were also examined. Unlike CDKN1A, CDKN2A (using primers for p16 and p14 but not when using p14-specific primers) was upregulated in both regions of colon. Compared with the number of genes appearing to upregulate in association with temporal age, more genes positively associated with increased CDKN2A expression (respectively, 16 and five of 44 genes studied for ascending and descending colon). Confirmation of increased expression of CDKN2A was sought by immunostaining for p16 in the myenteric plexus of colon from 52 patients, using a semi-automated software protocol. The results showed increased staining not within the glial cells (S100 stained), but in the cytoplasm of myenteric nerve cell bodies (MAP2 stained, with identified nucleus) of ascending, but not descending colon of the elderly, and not in the cell nucleus of either region or age group (5,710 neurons analyzed: n = 12-14 for each group). It was concluded that increased p16 staining within the cytoplasm of myenteric nerve cell bodies of elderly ascending (but not descending) colon, suggests a region-dependent, post-mitotic cellular senescence-like activity, perhaps involved with aging of enteric neurons within the colon

    What influences people’s responses to public health messages for managing risks and preventing infectious diseases? A rapid systematic review of the evidence and recommendations

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    Background: Individual behaviour changes, such as hand hygiene and physical distancing, are required on a population scale to reduce transmission of infectious diseases such as COVID-19. However, little is known about effective methods of communicating risk reducing information, and how populations might respond. Objective: To synthesise evidence relating to what (1) characterises effective public health messages for managing risk and preventing infectious disease and (2) influences people’s responses to messages. Design: A rapid systematic review was conducted. Protocol is published on Prospero CRD42020188704. Data sources: Electronic databases were searched: Ovid Medline, Ovid PsycINFO and Healthevidence. org, and grey literature (PsyarXiv, OSF Preprints) up to May 2020. Study selection: All study designs that (1) evaluated public health messaging interventions targeted at adults and (2) concerned a communicable disease spread via primary route of transmission of respiratory and/or touch were included. Outcomes included preventative behaviours, perceptions/awareness and intentions. Non-English language papers were excluded. Synthesis: Due to high heterogeneity studies were synthesised narratively focusing on determinants of intentions in the absence of measured adherence/ preventative behaviours. Themes were developed independently by two researchers and discussed within team to reach consensus. Recommendations were translated from narrative synthesis to provide evidence-based methods in providing effective messaging. Results: Sixty-eight eligible papers were identified. Characteristics of effective messaging include delivery by credible sources, community engagement, increasing awareness/knowledge, mapping to stage of epidemic/ pandemic. To influence intent effectively, public health messages need to be acceptable, increase understanding/perceptions of health threat and perceived susceptibility. Discussion: There are four key recommendations: (1) engage communities in development of messaging, (2) address uncertainty immediately and with transparency, (3) focus on unifying messages from sources and (4) frame messages aimed at increasing understanding, social responsibility and personal control. Embedding principles of behavioural science into public health messaging is an important step towards more effective health-risk communication during epidemics/pandemics

    A qualitative investigation of the health behaviours of young children from refugee families using Photo Elicitation Interviews

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    OBJECTIVES: To explore the experiences and perspectives of refugee parents regarding health behaviour changes among their children (i.e. changes in diet, levels of physical activity) and the impact of these changes on the health of their children aged 2–12 years. DESIGN: A qualitative approach using semi-structured interviews supported by photo-elicitation. METHODS: Parents of 2–12 years old children who had relocated to the UK within the past three or more years were recruited from two refugee organisations in the UK. Semi-structured face-to-face interviews and photo-elicitation were used to stimulate face-to-face in-depth discussions with participants. Data were analysed using an inductive and latent thematic analysis approach. RESULTS: Twenty-seven parent refugees were recruited. Participants were primarily mothers (85%) and from Syria (70%). Other countries of origin were Sudan, Eritrea, Iraq, Kuwait, Libya and Tunisia. Twenty-six interviews were conducted in Arabic and one in English. The analysis identified three themes: (1) Reflection on acculturation, (2) Changed parental role, and (3) Environmental barriers to being healthy. Participants described facing substantial changes to their lifestyle and personal context, including a restricted living space, restricted neighbourhood/community and inclement weather. These differences in the environment required parents to adjust their roles, and practices around their own and their child’s eating habits. These changes influenced refugee children’s health behaviours. Of particular concern to parents were increased sedentary behaviour and consumption of unhealthy snacks. CONCLUSIONS: Multiple factors were identified relating to changes in family circumstances and environments that influenced refugee children’s health behaviours. Targeting these behaviours in tailored interventions may help improve refugee children’s health

    What factors are associated with obesity‐related health behaviours among child refugees following resettlement in developed countries?:A systematic review and synthesis of qualitative and quantitative evidence

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    Refugee children are likely to become less active and eat more unhealthily after their resettlement in developed countries. This review aims to identify and synthesize research about factors that influence unhealthy behaviours related to obesity in this population. Six electronic databases were searched systematically to identify studies that sampled refugee children or parents of refugee children aged 2 to 16 years who have resettled in a developed country. Methodological and cultural study quality was assessed and factors associated with obesity‐related health behaviours investigated. Twenty studies fulfilled the inclusion criteria. Five major themes, representing factors influencing health behaviours, were identified from the data synthesis process: Acculturation, Environmental, Socioeconomic, Cognitive, and Family. The analysis revealed that refugee's health behaviours are influenced by several complex factors that are common to immigrant groups but have a greater influence among refugees. The review also revealed parental practices influence the health behaviours of children, especially those aged 2 to 10 years. Research is needed to understand further the role that parents have in influencing health behaviours and weight trajectories of children following resettlement

    Systematic review of interventions to promote the performance of physical distancing behaviours during infectious disease pandemics/epidemics

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    ObjectivesPhysical distancing, defined as keeping 1-2m apart when co-located, can prevent cases of droplet or aerosol transmitted infectious diseases such as SARS-CoV2. During the COVID-19 pandemic, distancing was a recommendation or a requirement in many countries. This systematic review aimed to determine which interventions and behavior change techniques (BCTs) are effective in promoting adherence to distancing and through which potential mechanisms of action (MOAs). MethodsSix databases were searched. The review included studies that were (a) conducted on humans, (b) reported physical distancing interventions, (c) included any comparator (e.g., pre-intervention versus post-intervention; randomized controlled trial) and (d) reported actual distancing or predictors of distancing behavior. Risk of bias was assessed using the Mixed Methods Appraisal Tool. BCTs and potential MoAs were identified in each intervention. ResultsSix papers indicated that distancing interventions could successfully change MoAs and behavior. Successful BCTs (MoAs) included feedback on behavior (e.g., motivation); information about health consequences, salience of health consequences (e.g., beliefs about consequences), demonstration (e.g., beliefs about capabilities) and restructuring the physical environment (e.g., environmental context and resources). The most promising interventions were proximity buzzers, directional systems and posters with loss-framed messages that demonstrated the behaviors. ConclusionsThe evidence indicates several BCTs and potential MoAs that should be targeted in interventions and highlights the gaps that should be focused on in future research.KEYWORDS: Systematic review; physical distancing; COVID-19; social distancingHighlights•Evaluates the effectiveness of interventions to promote distancing in pandemics•Six studies show that interventions can increase distancing •Key techniques: feedback, information about consequences, restructuring •Key delivery modes are posters and proximity buzzers•Further research is required to test more techniques and modes of delivery<br/

    An age-progression intervention for smoking cessation: A pilot study investigating the influence of two sets of instructions on intervention efficacy.

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    Background: Research on age-progression facial morphing interventions for smoking cessation has not investigated the effect of different instructions for intervention delivery. The objective of this pilot study was to investigate the influence of two instruction types used to deliver the intervention on efficacy of the intervention. Method: Women were recruited and randomly allocated to an age-progression intervention session with i) neutral instructions ii) instructions designed to reassure or iii) a condition that controlled for participant engagement (“control”). The conditions were delivered in a onetime procedure, after which primary (quitting intentions) and secondary (cigarettes/week, quit attempts) outcomes were measured immediately post-intervention, and at one- and three-months. Results: Seventy-two women (M = 25.7; SD = 0.9) were recruited and randomly allocated to condition (Neutral n = 27, Reassuring n = 22, Control n = 23). Quitting intentions were higher in the Reassuring versus Control arm (three months post-intervention, F = 4.37, p = 0.016, 95% CI [.231, 2.539], eta2 = .11); quit attempts were greater in the two intervention arms (58%) versus Control (one-month post-intervention, 15%) (2= 9.83, p &lt; .05, OR 1.00 [.28, 3.63]). Conclusions: Findings highlight the importance of optimising instructions to enhance intervention efficacy.<br/

    Scoping review of mobile phone app uptake and engagement to inform digital contract tracing tools for COVID-19

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    While researchers work to develop an effective COVID-19 vaccination, government and healthcare agencies across the world are developing and testing new ‘digital contact tracing’ technologies to help support the transition from emergency lockdown measures. During this transition phase, it is proposed that people will be able to move more freely, whilst ensuring continual monitoring and rapid action to tackle any new outbreaks of the COVID-19 virus
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