173 research outputs found

    Ketogenic diet modifies the gut microbiota in a murine model of autism spectrum disorder

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    BackgroundGastrointestinal dysfunction and gut microbial composition disturbances have been widely reported in autism spectrum disorder (ASD). This study examines whether gut microbiome disturbances are present in the BTBR(T + tf/j) (BTBR) mouse model of ASD and if the ketogenic diet, a diet previously shown to elicit therapeutic benefit in this mouse model, is capable of altering the profile.FindingsJuvenile male C57BL/6 (B6) and BTBR mice were fed a standard chow (CH, 13 % kcal fat) or ketogenic diet (KD, 75 % kcal fat) for 10-14 days. Following diets, fecal and cecal samples were collected for analysis. Main findings are as follows: (1) gut microbiota compositions of cecal and fecal samples were altered in BTBR compared to control mice, indicating that this model may be of utility in understanding gut-brain interactions in ASD; (2) KD consumption caused an anti-microbial-like effect by significantly decreasing total host bacterial abundance in cecal and fecal matter; (3) specific to BTBR animals, the KD counteracted the common ASD phenotype of a low Firmicutes to Bacteroidetes ratio in both sample types; and (4) the KD reversed elevated Akkermansia muciniphila content in the cecal and fecal matter of BTBR animals.ConclusionsResults indicate that consumption of a KD likely triggers reductions in total gut microbial counts and compositional remodeling in the BTBR mouse. These findings may explain, in part, the ability of a KD to mitigate some of the neurological symptoms associated with ASD in an animal model

    Mesenchymal Stem Cells Shift Mitochondrial Dynamics and Enhance Oxidative Phosphorylation in Recipient Cells

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    Mesenchymal stem cells (MSCs) are the most commonly used cells in tissue engineering and regenerative medicine. MSCs can promote host tissue repair through several different mechanisms including donor cell engraftment, release of cell signaling factors, and the transfer of healthy organelles to the host. In the present study, we examine the specific impacts of MSCs on mitochondrial morphology and function in host tissues. Employing in vitro cell culture of inherited mitochondrial disease and an in vivo animal experimental model of low-grade inflammation (high fat feeding), we show human-derived MSCs to alter mitochondrial function. MSC co-culture with skin fibroblasts from mitochondrial disease patients rescued aberrant mitochondrial morphology from a fission state to a more fused appearance indicating an effect of MSC co-culture on host cell mitochondrial network formation. In vivo experiments confirmed mitochondrial abundance and mitochondrial oxygen consumption rates were elevated in host tissues following MSC treatment. Furthermore, microarray profiling identified 226 genes with differential expression in the liver of animals treated with MSC, with cellular signaling, and actin cytoskeleton regulation as key upregulated processes. Collectively, our data indicate that MSC therapy rescues impaired mitochondrial morphology, enhances host metabolic capacity, and induces widespread host gene shifting. These results highlight the potential of MSCs to modulate mitochondria in both inherited and pathological disease states

    Corporate Security Responsibility: Towards a Conceptual Framework for a Comparative Research Agenda

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    The political debate about the role of business in armed conflicts has increasingly raised expectations as to governance contributions by private corporations in the fields of conflict prevention, peace-keeping and postconflict peace-building. This political agenda seems far ahead of the research agenda, in which the negative image of business in conflicts, seen as fuelling, prolonging and taking commercial advantage of violent conflicts,still prevails. So far the scientific community has been reluctant to extend the scope of research on ‘corporate social responsibility’ to the area of security in general and to intra-state armed conflicts in particular. As a consequence, there is no basis from which systematic knowledge can be generated about the conditions and the extent to which private corporations can fulfil the role expected of them in the political discourse. The research on positive contributions of private corporations to security amounts to unconnected in-depth case studies of specific corporations in specific conflict settings. Given this state of research, we develop a framework for a comparative research agenda to address the question: Under which circumstances and to what extent can private corporations be expected to contribute to public security

    A modified video-feedback intervention for carers of foster children aged 6 years and under with reactive attachment disorder : a feasibility study and pilot RCT

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    BACKGROUND: Looked-after children are at risk of suboptimal attachment patterns and reactive attachment disorder. However, access to interventions varies widely and there are no evidence-based interventions for this disorder. OBJECTIVES: (1) To adapt an existing video-feedback intervention to meet the specific needs of foster children in the UK with reactive attachment symptoms, (2) to conduct a case series to road-test the treatment manual and study procedures, (3) to conduct a scoping study of the key hurdles in a pilot trial and (4) to conduct a pilot randomised controlled trial of the adapted intervention to determine the feasibility of a future full-scale trial. DESIGN: This was a mixed-methods study. The adapted treatment manual was developed with expert input and tested on a small case series. Qualitative interviews with key stakeholders were used in the scoping study in preparation for the trial and later with foster carers who received the new intervention. The final stage was a feasibility and pilot randomised controlled trial of the new intervention, compared with usual care. Researchers assessing the outcomes were blinded to group assignment. SETTING: The study was set in outpatient child and adolescent mental health services and partner social services departments. Sites included urban and rural/semirural areas. PARTICIPANTS: Participants were foster carers with children aged ≤ 6 years presenting with difficulties in the domain of reactive attachment disorder. Key stakeholders included children's services managers and mental health service practitioners in the scoping study. Foster carers who received the modified intervention participated in qualitative interviews. INTERVENTION: The video-feedback intervention to promote positive parenting and sensitive discipline is an extensively evaluated and effective treatment approach. This intervention was modified (based on the adapted version for foster care in the Netherlands) to suit the needs of young children with reactive attachment symptoms in foster care in the UK and was delivered to improve the sensitive responding of foster carers, foster carer-child relationships and child outcomes. The modified intervention was delivered in-home by trained mental health professionals over a period of 4-6 months. MAIN OUTCOME MEASURE: The main outcome was reactive attachment symptom scores on the Disturbances of Attachment Interview. RESULTS: A series of minor changes to the intervention programme were introduced, which focused on improving its suitability for the UK foster care context. Challenges in recruitment meant that, despite numerous modifications to the protocol and the inclusion of additional sites, only 30 families (target, n = 40) were recruited to the randomised controlled trial (15 allocated to each group). However, most other trial parameters were deemed feasible and acceptable, particularly the high levels of data and treatment completeness. All randomised families were available for baseline analyses, but two in the treatment arm were not available for post-treatment analyses. The revised intervention was positively received by practitioners and foster carers. LIMITATIONS: Only three-quarters of the target sample size was recruited. Furthermore, the sites' own exclusion of potential participants and the low return rates of screening questionnaires raise the possibility of non-randomness of non-responses. CONCLUSION: A larger-scale trial may be feasible, but only if recruitment barriers can be overcome. Dedicated resources to support recruitment within local authorities and wider inclusion criteria are recommended. Central resourcing of intervention capacity to supplement NHS staff is also recommended. TRIAL REGISTRATION: This trial is registered as ISRCTN18374094. FUNDING: This project was funded by the National Institute for Health and Care Research ( NIHR ) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 35. See the NIHR Journals Library website for further project information

    Genetic Characterization of Physical Activity Behaviours in University Students Enrolled in Kinesiology Degree Programs

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    Studies of physical activity behaviours have increasingly shown the importance of heritable factors such as genetic variation. Non-synonymous polymorphisms of alpha-actinin 3 (ACTN3) and the β-adrenergic receptors 1 and 3 (ADRB) have been previously associated with exercise capacity and cardiometabolic health. We thus hypothesized that these polymorphisms are also related to physical activity behaviors in young adults. To test this hypothesis we examined relationships between ACTN3 (R577X), ARDB1 (Arg389Gly) and ADRB3 (Trp64Arg), and physical activity behaviors in university students. We stratified for student enrollment in kinesiology degree programs compared to non-majors as we previously found this to be a predictor of physical activity. We did not identify novel associations between physical activity and ACTN3. However, the minor alleles of ADRB1 and ADRB3 were significantly underrepresented in kinesiology students compared to non-majors. Furthermore, carriers of the ADRB1 minor allele reported reduced participation in moderate physical activity and increased afternoon fatigue compared to ancestral allele homozygotes. Together, these findings suggest that the heritability of physical activity behaviours in young adults may be linked to non-synonymous polymorphisms within β-adrenergic receptors.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

    Selection, characterization and application of new RNA HIV gp 120 aptamers for facile delivery of Dicer substrate siRNAs into HIV infected cells

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    The envelope glycoprotein of human immunodeficiency virus (HIV) consists of an exterior glycoprotein (gp120) and a trans-membrane domain (gp41) and has an important role in viral entry into cells. HIV-1 entry has been validated as a clinically relevant anti-viral strategy for drug discovery. In the present work, several 2′-F substituted RNA aptamers that bind to the HIV-1BaL gp120 protein with nanomole affinity were isolated from a RNA library by the SELEX (Systematic Evolution of Ligands by EXponential enrichment) procedure. From two of these aptamers we created a series of new dual inhibitory function anti-gp120 aptamer–siRNA chimeras. The aptamers and aptamer–siRNA chimeras specifically bind to and are internalized into cells expressing HIV gp160. The Dicer-substrate siRNA delivered by the aptamers is functionally processed by Dicer, resulting in specific inhibition of HIV-1 replication and infectivity in cultured CEM T-cells and primary blood mononuclear cells (PBMCs). Moreover, we have introduced a ‘sticky’ sequence onto a chemically synthesized aptamer which facilitates attachment of the Dicer substrate siRNAs for potential multiplexing. Our results provide a set of novel inhibitory agents for blocking HIV replication and further validate the use of aptamers for delivery of Dicer substrate siRNAs

    SurgiCal Obesity Treatment Study (SCOTS) : a prospective, observational cohort study on health and socioeconomic burden in treatment-seeking individuals with severe obesity in Scotland, UK

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    Objectives: There is a lack of evidence to inform the delivery and follow-up of bariatric surgery for people with severe obesity. The SurgiCal Obesity Treatment Study (SCOTS) is a national longitudinal cohort of people undergoing bariatric surgery. Here, we describe characteristics of the recruited SCOTS cohort, and the relationship between health and socioeconomic status with body mass index (BMI) and age. Participants/Methods: 445 participants scheduled for bariatric surgery at any of 14 centres in Scotland, UK, were recruited between 2013 and 2016 for this longitudinal cohort study (1 withdrawal); 249 completed health-related preoperative patient-reported outcome measures. Regression models were used to estimate the effect of a 10-unit increase in age or BMI, adjusting for sex, smoking and socioeconomic status. Results: Mean age was 46 years and median BMI was 47 kg/m2. For each 10 kg/m2 higher BMI, there was a change of −5.2 (95% CI −6.9 to –3.5; p<0.0001) in Rand 12-item Short Form Survey Physical Component Summary (SF-12 PCS), −0.1 (95% CI −0.2 to –0.1; p<0.0001) in EuroQoL 5-level EQ-5D version index score and 14.2 (95% CI 10.7 to 17.7; p<0.0001) in Impact of Weight on Quality of Life-Lite Physical Function Score. We observed a 3.1 times higher use of specialist aids and equipment at home (OR: 3.1, 95% CI 1.9 to 5.0; p<0.0001). Broadly, similar results were seen for each 10-year higher age, including a change of −2.1 (95% CI −3.7 to –0.5; p<0.01) in SF-12 PCS. Conclusions: A higher BMI combined with older age is associated with poor physical functioning and quality of life in people seeking bariatric surgery treatment. Policy-makers must consider the health and care needs of these individuals and invest to provide increased access to effective weight management. Trial registration number: ISRCTN47072588

    Mapping diphtheria-pertussis-tetanus vaccine coverage in Africa, 2000-2016: a spatial and temporal modelling study.

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    BACKGROUND: Routine childhood vaccination is among the most cost-effective, successful public health interventions available. Amid substantial investments to expand vaccine delivery throughout Africa and strengthen administrative reporting systems, most countries still require robust measures of local routine vaccine coverage and changes in geographical inequalities over time. METHODS: This analysis drew from 183 surveys done between 2000 and 2016, including data from 881 268 children in 49 African countries. We used a Bayesian geostatistical model calibrated to results from the Global Burden of Diseases, Injuries, and Risk Factors Study 2017, to produce annual estimates with high-spatial resolution (5 ×    5 km) of diphtheria-pertussis-tetanus (DPT) vaccine coverage and dropout for children aged 12-23 months in 52 African countries from 2000 to 2016. FINDINGS: Estimated third-dose (DPT3) coverage increased in 72·3% (95% uncertainty interval [UI] 64·6-80·3) of second-level administrative units in Africa from 2000 to 2016, but substantial geographical inequalities in DPT coverage remained across and within African countries. In 2016, DPT3 coverage at the second administrative (ie, district) level varied by more than 25% in 29 of 52 countries, with only two (Morocco and Rwanda) of 52 countries meeting the Global Vaccine Action Plan target of 80% DPT3 coverage or higher in all second-level administrative units with high confidence (posterior probability ≥95%). Large areas of low DPT3 coverage (≤50%) were identified in the Sahel, Somalia, eastern Ethiopia, and in Angola. Low first-dose (DPT1) coverage (≤50%) and high relative dropout (≥30%) together drove low DPT3 coverage across the Sahel, Somalia, eastern Ethiopia, Guinea, and Angola. INTERPRETATION: Despite substantial progress in Africa, marked national and subnational inequalities in DPT coverage persist throughout the continent. These results can help identify areas of low coverage and vaccine delivery system vulnerabilities and can ultimately support more precise targeting of resources to improve vaccine coverage and health outcomes for African children. FUNDING: Bill & Melinda Gates Foundation
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