Executive dysfunction and attention contribute to gait interference in ‘off’ state Parkinson's Disease

Motor and cognitive processes are required for successful ‘real world’ walking. We explored the specific contribution of motor function, executive function, and attention to functional gait performance in people with Parkinson's Disease (PD) when ‘off’ medication. Twenty-nine people with PD wearing an accelerometer were tested in their home whilst walking under four task conditions. Explanatory characteristics included age, motor function, executive function, sustained attention and divided attention. Repeated measures ANOVA compared gait speed under different task conditions. Multiple regression analysis explored the effect of characteristics on gait speed and gait interference (difference between dual and single task). Gait performance deteriorated under complex conditions (F = 51.0, P < .001). Motor function and attention explained up to 65% variance in gait speed. Motor function, attention and executive function explained up to 66% variance in gait interference. Sustained attention explained up to 10% variance in gait speed; executive function explained up to 21% variance in gait interference and divided attention explained up to 22% variance in gait interference. Motor function, executive function and attention contribute to gait speed and gait interference in PD during a functional walking task whilst ‘off’ medication. When both executive function and attention are included as explanatory variables, attention discriminates gait performance more effectively. Whilst both contribute to functional gait, they are used selectively to optimise performance for different conditions and to meet complex task requirements.     

Drivers for renewal and reform of contemporary nursing curricula: a blueprint for change

The creation of a curriculum blueprint appropriate to the development of a professional nurse who is practice-ready for the current and future context of health service delivery must take account of the extant context as well as an unpredictable and sometimes ambiguous future. The curriculum renewal process itself ought to challenge existing long held ideals, practices, and sacred cows within the health and higher education sectors. There is much to consider and importantly curriculum developers need to be mindful of reform within the health sector and health workforce education, as well as the concomitant vision and requirements of the nursing profession. Curriculum must develop more than discipline knowledge and skills: it must provide an infrastructure for generic abilities both social and intellectual in order to better prepare students for the registered nurse role. This paper discusses a number of forces that are essential to consider in curriculum development in undergraduate nursing education.     

Dental abnormalities after pediatric bone marrow transplantation

Our purpose was to describe the types and frequencies of altered dental development in pediatric patients following bone marrow transplantation (BMT). A retrospective review of the medical records and panoramic radiographs of all patients who underwent BMT at St Jude Children's Research Hospital between 1990 and 2000, for whom pre-BMT and post-BMT dental examination and panoramic radiography records were available, is presented. All patients were treated on institutional protocols. We recorded patient demographics and radiographic evidence of microdontia, hypodontia, taurodontia, root stunting, caries, enamel pearls, dental restorations/extractions and pulpal calcification. The 99 patients identified (52 males, 47 females) had a median age of 13.5 years (range, 3.4-25.9 years) at the time of BMT. In all, 73 were Caucasian, 15 were African-American, and 11 were of other races. The frequency of radiographically evident root stunting in permanent teeth was significantly increased after BMT (P<0.001), but there was no significant change in the frequency of other dental abnormalities after BMT. Dental abnormalities are prevalent in survivors of childhood BMT, but only root stunting appeared to progress with BMT.     

树突状细胞与肝脏疾病

免疫反应的产生首先是由抗原提呈细胞(antigenpresenting cells,APC)捕获抗原,经其加工处理后将抗原信息传递给T,B淋巴细胞,从而引发一系列的特异性免疫应答.APC包括树突状细胞(dendritic cells,DC)、巨噬细胞(MΦ)、B细胞等,其中DC是人体内最具潜能的抗原提呈细胞(APC),能在体内外直接激活纯真(naive)T细胞,提呈抗原给MHC-Ⅰ类限制性CD8+和MHC-Ⅱ类限制性CD4+T淋巴细胞,诱导特异性免疫应答[1-6].     

Recovery of contact hypersensitivity responses following murine bone marrow transplantation: comparison of gamma-irradiation and busulfan as preparative marrow-ablative agents

Bone marrow transplantation (BMT) is often followed by significant morbidity and mortality due to protracted immunodeficiency. We have hypothesized that the bone marrow-ablative regimen may delay the recovery of normal immune function following transplantation by impairing the interaction of host endothelial cells with circulating graft-derived lymphocytes. This report compares the relative effects of busulfan (an alkylating drug) and gamma-irradiation on the tissue- specific localization potential of lymphocytes and the eventual recovery of immune function within syngeneic murine transplant recipients. Localization of normal lymphocytes into peripheral lymph nodes of irradiated BMT recipients was markedly less (less than 50%) than in busulfan-treated or normal mice over the first 2 months post- BMT. This finding correlated with irradiation-induced endothelial cell edema and microvascular occlusions within lymphocyte-receptive areas of the nodal microvasculature. The effect of both preparative regimens on the recovery of contact hypersensitivity (CHS) was also analyzed. This response recovered more quickly (between 1 and 2 months) in busulfan- pretreated animals. Further experiments demonstrated that the decrease in CHS responsiveness appeared, in part, related to a depression in the capacity of lymphocytes to localize into skin sites of antigen deposition within irradiated mice. The impairment of tissue-specific lymphocyte localization may represent a novel mechanism by which whole body irradiation can contribute to delayed immunologic reconstitution following bone marrow transplantation.