209 research outputs found
Adolescent Sexuality and Culture: South African Mothers` Perspective
This study explores South African mothers’ perspective on adolescent sexuality within their cultural prism. Forty-four (44) mothers were purposefully selected for the study. Data was collected through six focus group discussions. The results indicated that culturally embedded reasons inhibited mothers from effectively imparting knowledge about sexuality to their daughters.Insufficient information, lack of role models and fear of sensitising their daughters to sexuality issues were other inhibitory factors.Keywords: Adolescent, sexuality, mothers, HIV and AIDS, sexual behaviour, culture
A temperature dependent virus binding assay reveals the presence of neutralising antibodies in human cytomegalovirus gB vaccine recipients’ sera
Human cytomegalovirus (HCMV) remains an important cause of mortality in immune-compromised transplant patients and following congenital infection. Such is the burden, an effective vaccine strategy is considered to be of the highest priority. The most successful vaccines to date have focused on generating immune responses against glycoprotein B (gB) – a protein essential for HCMV fusion and entry. We have previously reported that an important component of the humoral immune response elicited by gB/MF59 vaccination of patients awaiting transplant is the induction of non-neutralizing antibodies that target cell-associated virus with little evidence of concomitant classical neutralizing antibodies. Here we report that a modified neutralization assay that promotes prolonged binding of HCMV to the cell surface reveals the presence of neutralizing antibodies in sera taken from gB-vaccinated patients that cannot be detected using standard assays. We go on to show that this is not a general feature of gB-neutralizing antibodies, suggesting that specific antibody responses induced by vaccination could be important. Although we can find no evidence that these neutralizing antibody responses are a correlate of protection in vivo in transplant recipients their identification demonstrates the utility of the approach in identifying these responses. We hypothesize that further characterization has the potential to aid the identification of functions within gB that are important during the entry process and could potentially improve future vaccine strategies directed against gB if they prove to be effective against HCMV at higher concentrations
Seronegative patients vaccinated with cytomegalovirus gB-MF59 vaccine have evidence of neutralising antibody responses against gB early post-transplantation
Background
Human cytomegalovirus (HCMV) causes a ubiquitous infection which can pose a significant threat for immunocompromised individuals, such as those undergoing solid organ transplant (SOT). Arguably, the most successful vaccine studied to date is the recombinant glycoprotein-B (gB) with MF59 adjuvant which, in 3 Phase II trials, demonstrated 43–50% efficacy in preventing HCMV acquisition in seronegative healthy women or adolescents and reduction in virological parameters after SOT. However, the mechanism of vaccine protection in seronegative recipients remains undefined.
Methods
We evaluated samples from the cohort of seronegative SOT patients enroled in the Phase II glycoprotein-B/MF59 vaccine trial who received organs from seropositive donors. Samples after SOT (0–90 days) were tested by real-time quantitative PCR for HCMV DNA. Anti-gB antibody levels were measured by ELISA. Neutralization was measured as a decrease in infectivity for fibroblast cell cultures revealed by expression of immediate-early antigens.
Findings
Serological analyses revealed a more rapid increase in the humoral response against gB post transplant in vaccine recipients than in those randomised to receive placebo. Importantly, a number of patient sera displayed HCMV neutralising responses – neutralisation which was abrogated by pre-absorbing the sera with recombinant gB.
Interpretation
We hypothesise that the vaccine primed the immune system of seronegative recipients which, when further challenged with virus at time of transplant, allowed the host to mount rapid immunological humoral responses even under conditions of T cell immune suppression during transplantation
Seronegative patients vaccinated with cytomegalovirus gB-MF59 vaccine have evidence of neutralising antibody responses against gB early post-transplantation
Background
Human cytomegalovirus (HCMV) causes a ubiquitous infection which can pose a significant threat for immunocompromised individuals, such as those undergoing solid organ transplant (SOT). Arguably, the most successful vaccine studied to date is the recombinant glycoprotein-B (gB) with MF59 adjuvant which, in 3 Phase II trials, demonstrated 43–50% efficacy in preventing HCMV acquisition in seronegative healthy women or adolescents and reduction in virological parameters after SOT. However, the mechanism of vaccine protection in seronegative recipients remains undefined.
Methods
We evaluated samples from the cohort of seronegative SOT patients enroled in the Phase II glycoprotein-B/MF59 vaccine trial who received organs from seropositive donors. Samples after SOT (0–90 days) were tested by real-time quantitative PCR for HCMV DNA. Anti-gB antibody levels were measured by ELISA. Neutralization was measured as a decrease in infectivity for fibroblast cell cultures revealed by expression of immediate-early antigens.
Findings
Serological analyses revealed a more rapid increase in the humoral response against gB post transplant in vaccine recipients than in those randomised to receive placebo. Importantly, a number of patient sera displayed HCMV neutralising responses – neutralisation which was abrogated by pre-absorbing the sera with recombinant gB.
Interpretation
We hypothesise that the vaccine primed the immune system of seronegative recipients which, when further challenged with virus at time of transplant, allowed the host to mount rapid immunological humoral responses even under conditions of T cell immune suppression during transplantation
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A protocol paper: community engagement interventions for cardiovascular disease prevention in socially disadvantaged populations in the UK: an implementation research study
Background: Cardiovascular disorders (CVD) are the single greatest cause of mortality worldwide. In the UK, the National Health Service (NHS) has launched an initiative of health checks over and above current care to tackle CVD. However, the uptake of Health Checks is poor in disadvantaged communities. This protocol paper sets out a UK-based study (Sussex and Nottingham) aiming to co-produce a community delivered CVD risk assessment and coaching intervention to support community members to reduce their risk of CVD. The overall aim of the project is to implement a tailored-to-context community engagement (CE) intervention on awareness of CVD risks in vulnerable populations in high, middle and low-income countries. The specific objectives of the study are to enhance stakeholder' engagement; to implement lifestyle interventions for cardiovascular primary prevention, in disadvantaged populations and motivate uptake of NHS health checks.
Methods: This study uses both qualitative and quantitative methods in three phases of evaluation, including pre-, per-and post-implementation. To ensure contextual appropriateness the 'Scaling-up Packages of Interventions for Cardiovascular disease prevention in selected sites in Europe and Sub-Saharan Africa: An implementation research' (SPICES) project will organize a multi-component community-engagement intervention. For the qualitative component, the pre-implementation phase will involve a contextual assessment and stakeholder mapping, exploring potentials for CVD risk profiling strategies and led by trained Community Health Volunteers (CHV) to identify accessibility and acceptability. The per-implementation phase will involve healthy lifestyle counselling provided by CHVs and evaluation of the outcome to identify fidelity and scalability. The post-implementation phase will involve developing sustainable community-based strategies for CVD risk reduction. All three components will include a process evaluation. A stepped wedge cluster randomised trial of the roll out will focus on implementation outcomes including uptake and engagement and changes in risk profiles. The quantitative component includes pre and post-intervention surveys. The theory of the socio-ecological framework will be applied to analyse the community engagement approach.
Discussion: Based on the results ultimately a sustainable community engagement-based strategy for the primary prevention of CVD risk will be developed to enhance the performance of NHS health care in the UK. The Trial Registration number is ISRCTN68334579
Interplay between edge states and simple bulk defects in graphene nanoribbons
We study the interplay between the edge states and a single impurity in a
zigzag graphene nanoribbon. We use tight-binding exact diagonalization
techniques, as well as density functional theory calculations to obtain the
eigenvalue spectrum, the eigenfunctions, as well the dependence of the local
density of states (LDOS) on energy and position. We note that roughly half of
the unperturbed eigenstates in the spectrum of the finite-size ribbon hybridize
with the impurity state, and the corresponding eigenvalues are shifted with
respect to their unperturbed values. The maximum shift and hybridization occur
for a state whose energy is inverse proportional to the impurity potential;
this energy is that of the impurity peak in the DOS spectrum. We find that the
interference between the impurity and the edge gives rise to peculiar
modifications of the LDOS of the nanoribbon, in particular to oscillations of
the edge LDOS. These effects depend on the size of the system, and decay with
the distance between the edge and the impurity.Comment: 10 pages, 15 figures, revtex
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Nigerian cultural beliefs about mental health conditions and traditional healing: a qualitative study
Purpose: Cultural beliefs and traditions are integral to understanding indigenous mental health conditions (MHCs) and traditional healing. However, Nigerian cultural beliefs about MHCs and traditional healing are under-researched.
Design/methodology/approach: The study adopted a qualitative design using a critical realist and social constructionist perspectives to explore Nigerian mental health care practitioners (MHCPs) and lay participants (LPs) views regarding mental health conditions and traditional healing. Purposive and snowball sampling techniques were employed to select 53 participants (MHCPs = 26; LPs = 27; male = 32; female = 21) in four Nigerian cities (Ado-Ekiti, Enugu, Jos and Zaria). Data were collected using semi-structured interviews and analysed through thematic analyses.
Findings: The datasets revealed three overarching themes, namely: (i) existing cultural beliefs about MHCs as spiritual curse; (ii) description of traditional healing as the first treatment modality for MHCs; and (iii) perceived stigma associated with MHCs and help-seeking behaviours.
Originality/Practical implications: A study of Nigerian cultural beliefs and traditional healing contribute meaningfully to mental health systems. Future research and policy initiatives could explore ways of optimising traditional healing practices and community awareness programmes to increase access to mental health care in Nigeria
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