42 research outputs found

    DNA Immunization with Fusion of CTLA-4 to Hepatitis B Virus (HBV) Core Protein Enhanced Th2 Type Responses and Cleared HBV with an Accelerated Kinetic

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    BACKGROUND: Typically, DNA immunization via the intramuscular route induces specific, Th1-dominant immune responses. However, plasmids expressing viral proteins fused to cytotoxic T lymphocyte antigen 4 (CTLA-4) primed Th2-biased responses and were able to induced effective protection against viral challenge in the woodchuck model. Thus, we addressed the question in the mouse model how the Th1/Th2 bias of primed immune responses by a DNA vaccine influences hepatitis B virus (HBV) clearance. PRINCIPAL FINDINGS: Plasmids expressing HBV core protein (HBcAg) or HBV e antigen and HBcAg fused to the extracellular domain of CTLA-4 (pCTLA-4-HBc), CD27, and full length CD40L were constructed. Immunizations of these DNA plasmids induced HBcAg-specific antibody and cytotoxic T-cell responses in mice, but with different characteristics regarding the titers and subtypes of specific antibodies and intensity of T-cell responses. The plasmid pHBc expressing HBcAg induced an IgG2a-dominant response while immunizations of pCTLA-4-HBc induced a balanced IgG1/IgG2a response. To assess the protective values of the immune responses of different characteristics, mice were pre-immunized with pCTLA-4-HBc and pHBc, and challenged by hydrodynamic injection (HI) of pAAV/HBV1.2. HBV surface antigen (HBsAg) and DNA in peripheral blood and HBcAg in liver tissue were cleared with significantly accelerated kinetics in both groups. The clearance of HBsAg was completed within 16 days in immunized mice while more than 50% of the control mice are still positive for HBsAg on day 22. Stronger HBcAg-specific T-cell responses were primed by pHBc correlating with a more rapid decline of HBcAg expression in liver tissue, while anti-HBs antibody response developed rapidly in the mice immunized with pCTLA-4-HBc, indicating that the Th1/Th2 bias of vaccine-primed immune responses influences the mode of viral clearance. CONCLUSION: Viral clearance could be efficiently achieved by Th1/Th2-balanced immune response, with a small but significant shift in T-cell and B-cell immune responses

    Altered Intracellular Localization and Mobility of SBDS Protein upon Mutation in Shwachman-Diamond Syndrome

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    Shwachman-Diamond Syndrome (SDS) is a rare inherited disease caused by mutations in the SBDS gene. Hematopoietic defects, exocrine pancreas dysfunction and short stature are the most prominent clinical features. To gain understanding of the molecular properties of the ubiquitously expressed SBDS protein, we examined its intracellular localization and mobility by live cell imaging techniques. We observed that SBDS full-length protein was localized in both the nucleus and cytoplasm, whereas patient-related truncated SBDS protein isoforms localize predominantly to the nucleus. Also the nucleo-cytoplasmic trafficking of these patient-related SBDS proteins was disturbed. Further studies with a series of SBDS mutant proteins revealed that three distinct motifs determine the intracellular mobility of SBDS protein. A sumoylation motif in the C-terminal domain, that is lacking in patient SBDS proteins, was found to play a pivotal role in intracellular motility. Our structure-function analyses provide new insight into localization and motility of the SBDS protein, and show that patient-related mutant proteins are altered in their molecular properties, which may contribute to the clinical features observed in SDS patients

    Psychosocial Factors That Shape Patient and Carer Experiences of Dementia Diagnosis and Treatment : A Systematic Review of Qualitative Studies

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    Funding: This article presents independent research commissioned by the UK National Institute for Health Research (NIHR) under Research for Patient Benefit (Grant Reference Number PB-PG-0808-16024). The views expressed in this paper are those of the authors and not necessarily those of the NHS, the NIHR, nor the Department of Health. The sponsor of the study had no role in study design, data analysis, data interpretation or writing of the reportEarly diagnosis and intervention for people with dementia is increasingly considered a priority, but practitioners are concerned with the effects of earlier diagnosis and interventions on patients and caregivers. This systematic review evaluates the qualitative evidence about how people accommodate and adapt to the diagnosis of dementia and its immediate consequences, to guide practice. Methods and Findings: We systematically reviewed qualitative studies exploring experiences of community-dwelling individuals with dementia, and their carers, around diagnosis and the transition to becoming a person with dementia. We searched PubMed, PsychINFO, Embase, CINAHL, and the British Nursing Index (all searched in May 2010 with no date restrictions; PubMed search updated in February 2012), checked reference lists, and undertook citation searches in PubMed and Google Scholar (ongoing to September 2011). We used thematic synthesis to identify key themes, commonalities, barriers to earlier diagnosis, and support identified as helpful. We identified 126 papers reporting 102 studies including a total of 3,095 participants. Three overarching themes emerged from our analysis: (1) pathways through diagnosis, including its impact on identity, roles, and relationships; (2) resolving conflicts to accommodate a diagnosis, including the acceptability of support, focusing on the present or the future, and the use or avoidance of knowledge; and (3) strategies and support to minimise the impact of dementia. Consistent barriers to diagnosis include stigma, normalisation of symptoms, and lack of knowledge. Studies report a lack of specialist support particularly post-diagnosis. Conclusions: There is an extensive body of qualitative literature on the experiences of community-dwelling individuals with dementia on receiving and adapting to a diagnosis of dementia. We present a thematic analysis that could be useful to professionals working with people with dementia. We suggest that research emphasis should shift towards the development and evaluation of interventions, particularly those providing support after diagnosis.Peer reviewedFinal Published versio

    How do persons with dementia participate in decision making related to health and daily care? A multi-case study

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    Background Many countries have passed laws giving patients the right to participate in decisions about health care. People with dementia cannot be assumed to be incapable of making decisions on their diagnosis alone as they may have retained cognitive abilities. The purpose of this study was to gain a better understanding of how persons with dementia participated in making decisions about health care and how their family carers and professional caregivers influenced decision making. Methods This Norwegian study had a qualitative multi-case design. The triad in each of the ten cases consisted of the person with dementia, the family carer and the professional caregiver, in all 30 participants. Inclusion criteria for the persons with dementia were: (1) 67 years or older (2) diagnosed with dementia (3) Clinical Dementia Rating score 2, moderate dementia; (3) able to communicate verbally. The family carers and professional caregivers were then asked to participate. A semi-structured interview guide was used in interviews with family carers and professional caregivers. Field notes were written after participant observation of interactions between persons with dementia and professional caregivers during morning care or activities at a day centre. How the professional caregivers facilitated decision making was the focus of the observations that varied in length from 30 to 90 minutes. The data were analyzed using framework analysis combined with a hermeneutical interpretive approach. Results Professional caregivers based their assessment of mental competence on experience and not on standardized tests. Persons with dementia demonstrated variability in how they participated in decision making. Pseudo-autonomous decision making and delegating decision making were new categories that emerged. Autonomous decision making did occur but shared decision making was the most typical pattern. Reduced mental capacity, lack of available choices or not being given the opportunity to participate led to non-involvement. Not all decisions were based on logic; personal values and relationships were also considered. Conclusions Persons with moderate dementia demonstrated variability in how they participated in decision making. Optimal involvement was facilitated by positioning them as capable of influencing decisions, assessing decision-specific competence, clarifying values and understanding the significance of relationships and context
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