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

Forum: Focus groups for health research

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SB 148 - Amendments to the Nonprofit Code

The Act revises, simplifies, and modernizes the Georgia Nonprofit Corporation Code, providing greater flexibility in forming and running such organizations

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

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

The neurobiology of attention deficit/hyperactivity disorder.

ADHD is a brain based disorder with structural and functional abnormalities in widespread but specific areas of the brain. The most significant and consistent structural imaging findings include smaller total brain volumes, and reduced volumes in the right frontal lobe, right parietal cortex, caudate nucleus, cerebellar hemispheres, and posterior-inferior lobules of the cerebellar vermis. ADHD involves hypofunction of catecholaminergic circuits, particularly those that project to the prefrontal cortex. A minimum of 18 genes have been reported to be associated with the disorder; among them the DRD4 7-repeat allele has been found associated with a thinner prefrontal and posterior parietal cortex. Epigenetic factors acting during critical periods of prenatal and postnatal development may interact with genetic determinants. Methylphenidate, as well as the catecholaminergic nonstimulant atomoxetine, are effective in improving ADHD symptoms

Oscillatory activity in prefrontal and posterior regions during implicit letter-location binding.

Many cognitive abilities involve the integration of information from different modalities, a process referred to as “binding.” It remains less clear, however, whether the creation of bound representations occurs in an involuntary manner, and whether the links between the constituent features of an object are symmetrical. We used magnetoencephalography to investigate whether oscillatory brain activity related to binding processes would be observed in conditions in which participants maintain one feature only (involuntary binding); and whether this activity varies as a function of the feature attended to by participants (binding asymmetry). Participants performed two probe recognition tasks that were identical in terms of their perceptual characteristics and only differed with respect to the instructions given (to memorize either consonants or locations). MEG data were reconstructed using a current source distribution estimation in the classical frequency bands. We observed implicit verbal–spatial binding only when participants successfully maintained the identity of consonants, which was associated with a selective increase in oscillatory activity over prefrontal regions in all frequency bands during the first half of the retention period and accompanied by increased activity in posterior brain regions. The increase in oscillatory activity in prefrontal areas was only observed during the verbal task, which suggests that this activity might be signaling neural processes specifically involved in cross-code binding. Current results are in agreement with proposals suggesting that the prefrontal cortex function as a “pointer” which indexes the features that belong together within an object

Organization (Theory) As A Way of Life

To the extent that ‘classical organization theory’ is seen to possess any enduring interest it is mainly as a historic artefact. The idea that the principles, axioms, adages and devices elaborated by its proponents any longer possess traction in the present is rarely countenanced. In contrast to this customary view, the present article seeks to indicate the continuing significance of classical organization theory, for both analysing and intervening in organizational life. This necessitates a reconstruction of the conventional understanding of this received term, one in which classical organization theory is viewed less as ‘theory’ in the conventional sense, but rather as a geographically dispersed, institutionally disconnected and historically discontinuous ‘stance’, characterized, inter alia, by a pragmatist call to experience, an antithetical attitude to ‘high’ or transcendental theorizing, and, not least, an ethical focus on organizational effectiveness born of a close connection to ‘the work itself’ or ‘the situation at hand’. Deploying the term ‘classic organization theory’ in this way, to refer to a stance, attitude or comportment, and an associated persona that bears it, we are able to highlight the significant differences between this comportment and the increasingly ‘metaphysical’ attitude characterizing many contemporary approaches to organization and organizing, not simply in organization studies, but also more widely in sociology and cultural economy