1,207 research outputs found
Sustaining point-of-use (POU) water quality interventions in Ghana: the behavioural perspective
In Ghana, diarrhoeal diseases continue to be a major cause of under-five morbidity and mortality, mainly
due to faecally-contaminated household water and unhygienic practices. Although the West Africa Water
Initiative (WAWI) partnership has attained remarkable success in drilling boreholes and providing alternative
improved water sources in intervention communities in the Northern Region, promoting household water
treatment and safe storage products and technologies alongside is a cost effective alternative to reducing
diarrhoeal and other water-related diseases. This paper outlines the behaviour change perspective for
implementing household safe water treatment and storage technologies, based on a literature review. The
review highlights the health benefits of point-of-use water products, sources of water supply in WAWI intervention
communities, current water treatment and storage practices, the facilitating factors and obstacles
to behaviour change
Functional cooperation of xenoproteins after hamster‐to‐rat liver transplantation: With particular reference to hamster C3 and secretory component for rat IgA
Abstract: Long‐term survival after hamster‐to‐rat liver xenotransplantation has provided the opportunity to study the posttransplantation source of major serum proteins and the functional consequences of several different receptor‐ligand interactions, where one or the other is a xenogeneic protein. We report here that serum albumin, α‐1‐antitrypsin, complement component 3, and other acute phase reactants switch from recipient to donor origin during the first week after transplantation while serum immunoglobulins remain largely that of recipient. Despite the disparate source of complement (hamster) and immunoglobulins (rat), these two proteins were able to cooperate effectively to produce lysis of sheep red blood cells. Moreover, rat IgA was successfully processed by hamster hepatocytes and biliary epithelial cells, being present in the bile of successful liver xenograft recipients within one day after transplantation. The ability of these liver xenograft recipients to survive long‐term in conventional and viral‐free animal facilities without grossly obvious morbidity or unusual susceptibility to stress, suggests that xenogeneic proteins are able to successfully interact with several different physiologic I systems in the hamster‐to‐rat combination. © 1995 Munksgaar
Abnormal cingulum bundle development in autism: A probabilistic tractography study
There is now considerable evidence that white matter abnormalities play a role in the neurobiology of autism. Little research has been directed, however, at understanding (a) typical white matter development in autism and how this relates to neurocognitive impairments observed in the disorder. In this study we used probabilistic tractography to identify the cingulum bundle in 21 adolescents and young adults with Autism Spectrum Disorder (ASD), and 21 age- and sex-matched healthy volunteers. We investigated group differences in the relationships between age and fractional anisotropy, a putative measure of white matter integrity, within the cingulum bundle. Moreover, in a preliminary investigation, we examined the relationship between cingulum fractional anisotropy and executive functioning using the Behavior Rating Inventory of Executive Function (BRIEF). The ASD participants demonstrated significantly lower fractional anisotropy within the cingulum bundle compared to the typically developing volunteers. There was a significant group-by-age interaction such that the ASD group did not show the typical age-associated increases in fractional anisotropy observed among healthy individuals. Moreover, lower fractional anisotropy within the cingulum bundle was associated with worse BRIEF behavioral regulation index scores in the ASD group. The current findings implicate a dysregulation in cingulum bundle white matter development occurring in late adolescence and early adulthood in ASD, and suggest that greater disturbances in this trajectory are associated with executive dysfunction in ASD. (C) 2013 Elsevier Ireland Ltd. All rights reserved
The Neural Circuitry Mediating Shifts in Behavioral Response and Cognitive Set in Autism
Recent studies have suggested that the social and cognitive impairments in autism are associated with neural processing deficits in specific brain regions. However, these studies have primarily focused on neural systems responsible for face processing and social behaviors. Although repetitive, stereotyped behaviors are a hallmark of autism, little is known about the neural mechanisms underlying these behaviors in the disorder
Modulating perceptual complexity and load reveals degradation of the visual working memory network in ageing
Previous neuroimaging studies have reported a posterior to anterior shift of activation in ageing (PASA). Here, we explore the nature of this shift by modulating load (1,2 or 3 items) and perceptual complexity in two variants of a visual working memory task (VWM): a ‘simple’ color and a ‘complex’ shape change detection task. Functional near-infrared spectroscopy (fNIRS) was used to record changes in activation in younger (N=24) and older adults (N=24). Older adults exhibited PASA by showing lesser activation in the posterior cortex and greater activation in the anterior cortex when compared to younger adults. Further, they showed reduced accuracy at loads 2 and 3 for the simple task and across all loads for the complex task. Activation in the posterior and anterior cortices was modulated differently for younger and older adults. In older adults, increasing load in the simple task was accompanied by decreasing activation in the posterior cortex and lack of modulation in the anterior cortex, suggesting the inability to encode and/or maintain representations without much aid from higher-order centers. In the complex task, older adults recruited verbal working memory areas in the posterior cortex, suggesting that they used adaptive strategies such as labelling the shape stimuli. This was accompanied by reduced activation in the anterior cortex reflecting the inability to exert top-down modulation to typical VWM areas in the posterior cortex to improve behavioral performance
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Disorder-specific functional abnormalities during sustained attention in youth with Attention Deficit Hyperactivity Disorder (ADHD) and with Autism
Attention Deficit Hyperactivity Disorder (ADHD) and Autism Spectrum Disorder (ASD) are often comorbid and share behavioural-cognitive abnormalities in sustained attention. A key question is whether this shared cognitive phenotype is based on common or different underlying pathophysiologies. To elucidate this question, we compared 20 boys with ADHD to 20 age and IQ matched ASD and 20 healthy boys using functional magnetic resonance imaging (fMRI) during a parametrically modulated vigilance task with a progressively increasing load of sustained attention. ADHD and ASD boys had significantly reduced activation relative to controls in bilateral striato–thalamic regions, left dorsolateral prefrontal cortex (DLPFC) and superior parietal cortex. Both groups also displayed significantly increased precuneus activation relative to controls. Precuneus was negatively correlated with the DLPFC activation, and progressively more deactivated with increasing attention load in controls, but not patients, suggesting problems with deactivation of a task-related default mode network in both disorders. However, left DLPFC underactivation was significantly more pronounced in ADHD relative to ASD boys, which furthermore was associated with sustained performance measures that were only impaired in ADHD patients. ASD boys, on the other hand, had disorder-specific enhanced cerebellar activation relative to both ADHD and control boys, presumably reflecting compensation. The findings show that ADHD and ASD boys have both shared and disorder-specific abnormalities in brain function during sustained attention. Shared deficits were in fronto–striato–parietal activation and default mode suppression. Differences were a more severe DLPFC dysfunction in ADHD and a disorder-specific fronto–striato–cerebellar dysregulation in ASD
Osseous metaplasia in an ulcerating tubular adenoma of the colon: a case report
<p>Abstract</p> <p>Introduction</p> <p>Heterotopic bone is rarely found in the gastrointestinal tract. Here we report a rare case of metaplastic ossification within a benign ulcerating adenoma and review the literature concerning the aetiology.</p> <p>Case presentation</p> <p>A 63-year-old woman, who presented with a history of melaena, was found at colonoscopy to have a pedunculated ulcerating polyp. Histological examination demonstrated multiple areas of osseous metaplasia within the polyp stroma.</p> <p>Conclusion</p> <p>Heterotopic ossification in colonic adenomas is a particularly rare phenomenon, with the majority of cases occurring within malignant lesions. The suggested mechanisms for its aetiology still remain unclear.</p
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