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991.
The mechanisms of T cell vaccination (TCV) are still unclear, especially the molecular interactions for recognition of autoreactive T cells by the immune system. Here we investigated the role of CD28:B7 interaction in TCV-induced protection in the murine EAE model. We demonstrate that there is increased expression of both B7-1 and B7-2 on autoreactive Th1 cells compared to Th2 cells. Blockade of B7 on the vaccinating autoreactive T cell surface or blockade of CD28 in recipient mice reduced the protective effect of TCV. Furthermore, we showed that TCV significantly inhibited Ag-specific CD4 and CD8 T cell proliferation and decreased Ag-specific IFN-gamma production by CD4 T cells in mice undergoing TCV, and blocking of B7 on the surface of vaccinating T cells reduced this inhibition on Ag-specific CD4 and CD8 T cell proliferation, more significantly on Ag-specific CD4 T cell proliferation. These data indicated that B7 expression on autoreactive T cells is necessary for the recognition of autoreactive T cells by the immune system and subsequent protection from EAE in mice undergoing TCV.  相似文献   
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It has been previously shown that the interaction of some weakly basic drugs with oppositely charged fatty acids during digestion can influence the solid-state form of the drug if it precipitates. The present study hypothesized the opposite effect for weakly acidic drugs. Tolfenamic acid (TA) and an oppositely charged cationic surfactant, didodecyldimethylammonium bromide (DDAB) were combined in a model medium chain lipid formulation. The phase distribution upon in vitro lipolysis was determined using HPLC and the solid-state form of precipitated TA was determined using X-ray diffraction and crossed polarized light microscopy. TA precipitated in a different polymorphic crystalline form to the starting reference material in the absence of DDAB but precipitated in an amorphous form when DDAB was included in the same formulation. The solubility of TA upon dispersion and digestion of the formulation was considerably higher in the presence of DDAB. The findings point to ionic interactions between TA and DDAB as the reason for the improved drug solubility throughout digestion, and precipitation of drug in an amorphous salt form, analogous to what has been observed in the past for some poorly water-soluble weakly basic drugs with anionic co-formers.  相似文献   
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Ischaemia reperfusion (I/R) is associated with liver injury and impaired regeneration during partial hepatectomy (PH). The aim of this study was to investigate the effect of thymoquinone (TQ), the active compound of essential oil obtained from Nigella sativa seeds, on rat liver after PH. Male Wistar rats were divided equally into four groups (n = 6) receiving an oral administration of either vehicle solution (sham and PH groups) or TQ at 30 mg/kg (TQ and TQ + PH groups) for 10 consecutive days. Then, rats underwent PH (70%) with 60 minutes of ischaemia followed by 24 hours of reperfusion (PH and TQ + PH groups). Alanine aminotransferase (ALT) activity and histopathological damage were determined. Also, antioxidant parameters, liver regeneration index, hepatic adenosine triphosphate (ATP) content, endoplasmic reticulum (ER) stress and apoptosis were assessed. In response to PH under I/R, liver damage was significantly alleviated by TQ treatment as evidenced by the decrease in ALT activity (P < .01) and histological findings (P < .001). In parallel, TQ preconditioning increased hepatic antioxidant capacities. Moreover, TQ improved mitochondrial function (ATP, P < .05), attenuated ER stress parameters and repressed the expression of apoptotic effectors. Taken together, our results suggest that TQ preconditioning could be an effective strategy to reduce liver injury after PH under I/R. The protective effects were mediated by the increase of antioxidant capacities and the decrease of ER stress and apoptosis.  相似文献   
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Background

In recent years, greater emphasis has been placed on gambling venues to identify potential problem gamblers, respond appropriately and refer to treatment. In seeking the perspectives of problem gamblers, venue staff and treatment providers, this qualitative study investigates how problem gamblers experience being identified and referred for treatment by venue staff.

Methods

A semi-structured interview guide focusing on experiences and perceptions of problem gambling identification and referral for treatment in gaming venues was used to conduct 4 focus groups and 9 semi-structured in-depth interviews. Participants comprised 22 problem gamblers, 10 gambling venue staff and 8 problem gambling counsellors. Audio recordings were transcribed verbatim, and an interpretive phenomenological analysis was conducted.

Results

‘Role conflict’ was identified as a considerable source of stress for venue staff who described conflicting priorities in responding to problem gamblers whilst maintaining employer profit margins. Problem gamblers described offers of help from venue staff as hypocritical and disingenuous. Venue staff also described reluctance to make moral judgements through the identification of and engagement with problem gamblers, and gamblers described resentment in being singled out and targeted as a problem gambler. Being approached and offered referral to a counselling service was a rare occurrence among problem gamblers. This corresponded with reports by gambling counsellors.

Conclusions

Role conflict experienced by gambling venue staff and patrons alike inhibits effective referral of potential problem gamblers into treatment. Reducing the need for gambling venue staff to make a perceived moral judgement about the gambling behaviours of specific patrons may improve the reception of responsible gambling information and promote help-seeking.
  相似文献   
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Surveys indicate that many Australians would prefer to die at home, but relatively few do. Recognising that patients and their families may not have the support they need to enable end‐of‐life care at home, a consortium of care providers developed, and received funding to trial, the Palliative Care Home Support Program (PCHSP) across seven health districts in New South Wales, Australia. The programme aimed to supplement end‐of‐life care in the home provided by existing multidisciplinary community palliative care teams, with specialist supportive community care workers (CCWs). An evaluation of the service was undertaken, focussing on the self‐reported impact of the service on family carers (FCs), with triangulation of findings from community palliative care teams and CCWs. Service evaluation data were obtained through postal surveys and/or qualitative interviews with FCs, community palliative care teams and CCWs. FCs also reported the experience of their loved one based on 10 items drawn from the Quality of Death and Dying Questionnaire (QODD). Thematic analysis of surveys and interviews found that the support provided by CCWs was valued by FCs for: enabling choice (i.e. to realise end‐of‐life care in the home); providing practical assistance (“hands‐on”); and for emotional support and reassurance. This was corroborated by community palliative care teams and CCWs. Responses by FCs on the QODD items indicated that in the last week of life, effective control of symptoms was occurring and quality of life was being maintained. This study suggests that satisfactory outcomes for patients and their families who wish to have end‐of‐life care in the home can be enabled with the additional support of specially trained CCWs. A notable benefit of the PCHSP model, which provided specific palliative care vocational training to an existing community care workforce, was a relatively rapid increase in the palliative care workforce across the state.  相似文献   
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