181 research outputs found

    Plasticity in the human hippocampus

    Get PDF
    If we are to approach rehabilitation of memory-impaired patients in a systematic and efficacious way, then it is vital to know if the human memory system has the propensity for plasticity in adulthood, the limiting factors on such plasticity, and the timescales of any plastic change. This thesis was motivated by an attempt to develop a body of knowledge in relation to these questions. There is wide agreement that the hippocampus plays a key role in navigation and memory across species. Evidence from animal studies suggests that spatial memoryrelated hippocampal volume changes and experience-related hippocampal neurogenesis takes place throughout the lifespan. Previous studies in humans indicated that expert navigators, licensed London taxi drivers, have different patterns of hippocampal grey matter volume relative to control participants. In addition, preliminary evidence also suggested there may be functional consequences associated with this grey matter pattern. Using licensed London taxi drivers as a model for learning and memory, the work undertaken centered on four key issues: (1) In a set of studies, I characterised the neuropsychological profile of licensed London taxi drivers in detail, which included devising a number of new table-top associational memory tests. This enabled me to assess the functional consequences of their expertise and hippocampal grey matter pattern in greater depth than previous studies. (2) In order to explore the effects of taxi drivers’ expertise in more naturalistic settings, I also examined how well they could learn the layout of an unfamiliar town compared with a group of non-taxi drivers, and how effectively taxi drivers could integrate a new district into their existing spatial representation of London. (3) I then conducted a study on experts whose knowledge was much less spatial than taxi drivers in order to examine if the effects on hippocampal grey matter and neuropsychology were general or whether they were specific to the spatial domain. (4) Given that previous taxi driver studies were cross-sectional, the question of whether the human hippocampus can exhibit spatial memory-related structural plasticity in adulthood was uncertain. I therefore conducted a longitudinal study which assessed participants both pre and post taxi driver training using structural MRI and neuropsychological measures. This enabled me to investigate, within subjects, whether hippocampal volume changes can be acquired in response to intense spatial stimulation. In addition, I explored whether ceasing to be a taxi driver (i.e. retiring after many years on the job) resulted in ‘reverse’ plasticity. I found evidence for hippocampal plasticity within individuals as a result of their intense acquisition of spatial knowledge over a number of years that was associated with qualifying to be a licensed London taxi driver, and preliminary evidence of reverse plasticity when taxi drivers retire. This suggests that hippocampal structure and memory ability can be modified in response to environmental factors and are not necessarily hard-wired. However, my results also provide some insights into the boundaries within which human memory operates, as I identified both positive and negative cognitive consequences of being an expert navigator, and also established that the MRI and neuropsychology effects of expertise on the hippocampus may be restricted to the spatial domain

    Management of mental health disorders in HIV-positive patients

    Get PDF
    These guidelines are intended as a reference document to assist HIV nurse and doctor clinicians in managing mental health disorders. It is intended to improve awareness, knowledge and capacity to support patients living with HIV and mental health disorders

    ‘They’re more like ordinary stroppy British women’: Attitudes and expectations of maternity care professionals to UK-born ethnic minority women

    Get PDF
    Objective To explore the attitudes and expectations of maternity care professionals to UK-born ethnic minority mothers. Methods Qualitative in-depth interviews with 30 professionals from eight NHS maternity units in England that provide services for large proportions of women of black Caribbean, black African, Indian, Pakistani and Irish descent. Results All the professionals reported providing care to both UK-born and migrant mothers from ethnic minorities. Most of them felt that they could differentiate between UK-born and migrant mothers based mainly on language fluency and accent. ‘Westernized dress’ and ‘freedom’ were also cited as indicators. Overall, professionals found it easier to provide services to UK-born mothers and felt that their needs were more like those of white English mothers than those of migrant mothers. UK-born mothers were generally thought to be assertive and expressive, and in control of care-related decision-making whereas some South Asian Muslim women were thought to be constrained by family influences. Preconceived ideas about ethnic minority mothers' tolerance of pain in labour, use of pharmacological pain relief measures and mode of delivery were recurring themes. Women's education and social class were felt to be major influences on the uptake of maternity care, regardless of ethnicity. Conclusions Professionals appeared to equate the needs of UK-born ethnic minority women with those of white English women. Overall, this has positive implications for care provision. Despite this, specific behavioural expectations and unconscious stereotypical views were evident and have the potential to affect clinical practice

    Outcomes of a randomized controlled trial assessing a smartphone Application to reduce unmet needs among people diagnosed with CancEr (ACE)

    Get PDF
    © 2019 The Authors. Cancer Medicine published by John Wiley & Sons Ltd. Background: Smartphone technology represents an opportunity to deliver practical solutions for people affected by cancer at a scale that was previously unimaginable, such as information, appointment monitoring, and improved access to cancer support services. This study aimed to determine whether a smartphone application (app) reduced the unmet needs among people newly diagnosed with cancer. Methods: A single blind, multisite randomized controlled trial to determine the impact of an app-based, 4-month intervention. Newly diagnosed cancer patients were approached at three health service treatment clinics. Results: Eighty-two people were randomized (intervention; n = 43 and control; n = 39), average age was 59.5 years (SD: 12.9); 71% female; 67% married or in a de facto relationship. At baseline, there were no differences in participants’ characteristics between the groups. No significant effects, in reducing unmet needs, were demonstrated at the end of intervention (4-month) or 12-month follow-up. Overall, 94% used the app in weeks 1-4, which decreased to 41% in weeks 13-16. Mean app use time per participant: Cancer Information, 6.9 (SD: 18.9) minutes; Appointment Schedule, 5.1 (SD: 9.6) minutes; Cancer Services 1.5 minutes (SD: 6.8); Hospital Navigation, 1.4 (SD: 2.8) minutes. Conclusions: Despite consumer involvement in the design of this smartphone technology, the app did not reduce unmet needs. This may have been due to the study being underpowered. To contribute to a meaningful understanding and improved implementation of smartphone technology to support people affected by cancer, practical considerations, such as recruitment issues and access to, and confidence with, apps, need to be considered. Australian New Zealand Clinical Trials Registration (ACTRN) Trial Registration: 12616001251415; WEF 7/9/2016

    Socio-cultural influences on the behaviour of South Asian women with diabetes in pregnancy: qualitative study using a multi-level theoretical approach

    Get PDF
    BACKGROUND: Diabetes in pregnancy is common in South Asians, especially those from low-income backgrounds, and leads to short-term morbidity and longer-term metabolic programming in mother and offspring. We sought to understand the multiple influences on behaviour (hence risks to metabolic health) of South Asian mothers and their unborn child, theorise how these influences interact and build over time, and inform the design of culturally congruent, multi-level interventions. METHODS: Our sample for this qualitative study was 45 women of Bangladeshi, Indian, Sri Lankan, or Pakistani origin aged 21-45 years with a history of diabetes in pregnancy, recruited from diabetes and antenatal services in two deprived London boroughs. Overall, 17 women shared their experiences of diabetes, pregnancy, and health services in group discussions and 28 women gave individual narrative interviews, facilitated by multilingual researchers, audiotaped, translated, and transcribed. Data were analysed using the constant comparative method, drawing on sociological and narrative theories. RESULTS: Key storylines (over-arching narratives) recurred across all ethnic groups studied. Short-term storylines depicted the experience of diabetic pregnancy as stressful, difficult to control, and associated with negative symptoms, especially tiredness. Taking exercise and restricting diet often worsened these symptoms and conflicted with advice from relatives and peers. Many women believed that exercise in pregnancy would damage the fetus and drain the mother's strength, and that eating would be strength-giving for mother and fetus. These short-term storylines were nested within medium-term storylines about family life, especially the cultural, practical, and material constraints of the traditional South Asian wife and mother role and past experiences of illness and healthcare, and within longer-term storylines about genetic, cultural, and material heritage - including migration, acculturation, and family memories of food insecurity. While peer advice was familiar, meaningful, and morally resonant, health education advice from clinicians was usually unfamiliar and devoid of cultural meaning. CONCLUSIONS: 'Behaviour change' interventions aimed at preventing and managing diabetes in South Asian women before and during pregnancy are likely to be ineffective if delivered in a socio-cultural vacuum. Individual education should be supplemented with community-level interventions to address the socio-material constraints and cultural frames within which behavioural 'choices' are made

    Resveratrol Delays Age-Related Deterioration and Mimics Transcriptional Aspects of Dietary Restriction without Extending Life Span

    Get PDF
    22 páginas, 4 figuras.A small molecule that safely mimics the ability of dietary restriction (DR) to delay age-related diseases in laboratory animals is greatly sought after. We and others have shown that resveratrol mimics effects of DR in lower organisms. In mice, we find that resveratrol induces gene expression patterns in multiple tissues that parallel those induced by DR and every-other-day feeding. Moreover, resveratrol-fed elderly mice show a marked reduction in signs of aging, including reduced albuminuria, decreased inflammation, and apoptosis in the vascular endothelium, increased aortic elasticity, greater motor coordination, reduced cataract formation, and preserved bone mineral density. However, mice fed a standard diet did not live longer when treated with resveratrol beginning at 12 months of age. Our findings indicate that resveratrol treatment has a range of beneficial effects in mice but does not increase the longevity of ad libitum-fed animals when started midlife.This work was supported by grants from the American Heart Association (0425834T to J.A.B. and 0435140N to A.C.) and from the NIH (RO1GM068072, AG19972, and AG19719 to D.A.S.), (HL077256 to Z.U.), (HD034089 to L.W), (2RO1 EY011733 to N.S.W.), Spanish grant (BFU2005-03017 to P.N.), and by the generous support of Mr. Paul F. Glenn and The Paul F. Glenn Laboratories for the Biological Mechanisms of Aging.Peer reviewe

    HacA-Independent Functions of the ER Stress Sensor IreA Synergize with the Canonical UPR to Influence Virulence Traits in Aspergillus fumigatus

    Get PDF
    Endoplasmic reticulum (ER) stress is a condition in which the protein folding capacity of the ER becomes overwhelmed by an increased demand for secretion or by exposure to compounds that disrupt ER homeostasis. In yeast and other fungi, the accumulation of unfolded proteins is detected by the ER-transmembrane sensor IreA/Ire1, which responds by cleaving an intron from the downstream cytoplasmic mRNA HacA/Hac1, allowing for the translation of a transcription factor that coordinates a series of adaptive responses that are collectively known as the unfolded protein response (UPR). Here, we examined the contribution of IreA to growth and virulence in the human fungal pathogen Aspergillus fumigatus. Gene expression profiling revealed that A. fumigatus IreA signals predominantly through the canonical IreA-HacA pathway under conditions of severe ER stress. However, in the absence of ER stress IreA controls dual signaling circuits that are both HacA-dependent and HacA-independent. We found that a ΔireA mutant was avirulent in a mouse model of invasive aspergillosis, which contrasts the partial virulence of a ΔhacA mutant, suggesting that IreA contributes to pathogenesis independently of HacA. In support of this conclusion, we found that the ΔireA mutant had more severe defects in the expression of multiple virulence-related traits relative to ΔhacA, including reduced thermotolerance, decreased nutritional versatility, impaired growth under hypoxia, altered cell wall and membrane composition, and increased susceptibility to azole antifungals. In addition, full or partial virulence could be restored to the ΔireA mutant by complementation with either the induced form of the hacA mRNA, hacAi, or an ireA deletion mutant that was incapable of processing the hacA mRNA, ireAΔ10. Together, these findings demonstrate that IreA has both HacA-dependent and HacA-independent functions that contribute to the expression of traits that are essential for virulence in A. fumigatus

    Critical views on postpartum care expressed by new mothers

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Women's evaluation of hospital postpartum care has consistently been more negative than their assessment of other types of maternity care. The need to further explore what is wrong with postpartum care, in order to stimulate changes and improvements, has been stressed. The principal aim of this study was to describe women's negative experiences of hospital postpartum care, expressed in their own words. Characteristics of the women who spontaneously gave negative comments about postpartum care were compared with those who did not.</p> <p>Methods</p> <p>Data were taken from a population-based prospective longitudinal study of 2783 Swedish-speaking women surveyed at three time points: in early pregnancy, at two months, and at one year postpartum. At the end of the two follow-up questionnaires, women were asked to add any comment they wished. Content analysis of their statements was performed.</p> <p>Results</p> <p>Altogether 150 women gave negative comments about postpartum care, and this sample was largely representative of the total population-based cohort. The women gave a diverse and detailed description of their experiences, for instance about lack of opportunity to rest and recover, difficulty in getting individualised information and breastfeeding support, and appropriate symptom management. The different statements were summarised in six categories: organisation and environment, staff attitudes and behaviour, breastfeeding support, information, the role of the father and attention to the mother.</p> <p>Conclusion</p> <p>The findings of this study underline the need to further discuss and specify the aims of postpartum care. The challenge of providing high-quality follow-up after childbirth is discussed in the light of a development characterised by a continuous reduction in the length of hospital stay, in combination with increasing public demands for information and individualised care.</p
    corecore