Dietary and fluid adherence among haemodialysis patients attending public sector hospitals in the Western Cape

Objective There has been considerable debate about the extent to which social cognitive models of health behaviour apply in developing countries. The purpose of this paper was to determine the applicability of the Theory of Planned Behaviour (TPB) in predicting dietary and fluid adherence among a sample of haemodialysis patients attending public sector hospitals in the Western Cape. Design and methods A sample of 62 historically disadvantaged patients undergoing haemodialysis completed a battery of psychometric instruments measuring attitudes, subjective norms, perceived behavioural control regarding dietary and fluid adherence, health literacy, perceived social support, and self-reported dietary and fluid adherence. Interdialytic weight gain (IDWG), predialytic serum potassium levels, and predialytic serum phosphate levels served as biochemical indicators of dietary and fluid adherence. Results Regression analyses indicated that the linear combination of attitudes and perceived behavioural control significantly accounted for 15.5% of the variance in self-reported adherence (a medium-effect size) and 11.4% of the variance in IDWG (a modest-effect size). No significant predictors were identified for predialytic serum potassium and predialytic serum phosphate levels. Interpretation and conclusions The results indicate that, while the TPB may not function in the same manner as it does in Western samples, it may have some nuanced applicability among haemodialysis patients attending public sector hospitals in the Western Cape. SAJCN Vol. 21 (2) 2008: pp. 7-1

Screening for HIV-related PTSD: Sensitivity and specificity of the 17-item Posttraumatic Stress Diagnostic Scale (PDS) in identifying HIV-related PTSD among a South African sample

Objectives: The identification of HIV-positive patients who exhibit criteria for Post traumatic Stress Disorder (PTSD) and related trauma symptomatology is of clinical importance in the maintenance of their overall wellbeing. This study assessed the sensitivity and specificity of the 17-item Post traumatic Stress Diagnostic Scale (PDS), a self-report instrument, in the detection of HIVrelated PTSD. An adapted version of the PTSD module of the Composite International Diagnostic Interview (CIDI) served as the gold standard. Method: 85 HIV-positive patients diagnosed with HIV within the year preceding data collection were recruited by means of convenience sampling from three HIV clinics within primary health care facilities in the Boland region of South Africa. Results: A significant association was found between the 17-item PDS and the adapted PTSD module of the CIDI. A ROC curve analysis indicated that the 17-item PDS correctly discriminated between PTSD caseness and non-caseness 74.9% of the time. Moreover, a PDS cut-off point of ≥ 15 yielded adequate sensitivity (68%) and 1-specificity (65%). The 17-item PDS demonstrated a PPV of 76.0% and a NPV of 56.7%. Conclusion: The 17-item PDS can be used as a brief screening measure for the detection of HIV-related PTSD among HIV-positive patients in South Africa.Key Words: ROC analysis; Posttraumatic Stress Diagnostic Scale (PDS); Composite International Diagnostic Interview (CIDI); South Afric

A Late Quaternary Paleoecological Record From Caves of Southern Jamaica, West Indies

Studies of an unusual and diverse system of caves in coastal southern Jamaica have yielded a paleoclimatic record associated with a fossil vertebrate record that provides useful insights into the poorly documented paleoecology of latest Wisconsinan and Holocene Jamaica. Episodes of significantly increased precipitation during the Holocene have left characteristic deposits of speleothems, and have supported both faunal and archaeological communities that were dependent on these mesic conditions. Deposits of fossil bat guano preserved in the caves provide a δ¹³C record of alternating mesic and xeric climatic episodes that supports the interpretation of the faunal and archaeological record

Between innovation and legitimation : boundaries and knowledge flow in management consultancy

Management consultancy is seen by many as a key agent in the adoption of new management ideas and practices in organizations. Two contrasting views are dominant—consultants as innovators, bringing new knowledge to their clients or as legitimating client knowledge. Those few studies which examine directly the flow of knowledge through consultancy in projects with clients favour the innovator view and highlight the important analytical and practical value of boundaries— consultants as both knowledge and organizational outsiders. Likewise, in the legitimator view, the consultants’ role is seen in terms of the primacy of the organizational boundary. By drawing on a wider social science literature on boundaries and studies of inter-organizational knowledge flow and management consultancy more generally, this polarity is seen as problematic, especially at the level of the consulting project. An alternative framework of boundary relations is developed and presented which incorporates their multiplicity, dynamism and situational specificity. This points to a greater complexity and variability in knowledge flow and its potential than is currently recognized. This is significant not only in terms of our understanding of management consultancy and inter-organizational knowledge dynamics and boundaries, but of a critical understanding of the role of management consultancy more generally

Neurospora crassa suppressors act on amber

Neurospora crassa suppressors act on ambe

Feeling Tired?: How Sharing Positive Experiences Can Boost Vitality

Three studies indicated how sharing positive experiences can boost vitality

Posterior Vitreous Detachment and the Posterior Hyaloid Membrane

PURPOSE: Despite posterior vitreous detachment being a common ocular event affecting most individuals in an aging population, there is little consensus regarding its precise anatomic definition. We investigated the morphologic appearance and molecular composition of the posterior hyaloid membrane to determine whether the structure clinically observed enveloping the posterior vitreous surface after posterior vitreous detachment is a true basement membrane and to postulate its origin. Understanding the relationship between the vitreous (in both its attached and detached state) and the internal limiting membrane of the retina is essential to understanding the cause of rhegmatogenous retinal detachment and vitreoretinal interface disorders, as well as potential future prophylactic and treatment strategies. DESIGN: Clinicohistologic correlation study. PARTICIPANTS: Thirty-six human donor globes. METHODS: Vitreous bodies identified to have posterior vitreous detachment were examined with phase-contrast microscopy and confocal microscopy after immunohistochemically staining for collagen IV basement membrane markers, in addition to extracellular proteins that characterize the vitreoretinal junction (fibronectin, laminin) and vitreous gel (opticin) markers. The posterior retina similarly was stained to evaluate the internal limiting membrane. Findings were correlated to the clinical appearance of the posterior hyaloid membrane observed during slit-lamp biomicroscopy after posterior vitreous detachment and compared with previously published studies. MAIN OUTCOME MEASURES: Morphologic appearance and molecular composition of the posterior hyaloid membrane. RESULTS: Phase-contrast microscopy consistently identified a creased and distinct glassy membranous sheet enveloping the posterior vitreous surface, correlating closely with the posterior hyaloid membrane observed during slit-lamp biomicroscopy in patients with posterior vitreous detachment. Immunofluorescent confocal micrographs demonstrated the enveloping membranous structure identified on phase-contrast microscopy to show positive stain results for type IV collagen. Immunofluorescence of the residual intact internal limiting membrane on the retinal surface also showed positive stain results for type IV collagen. CONCLUSIONS: The results of this study provide immunohistochemical evidence that the posterior hyaloid membrane is a true basement membrane enveloping the posterior hyaloid surface. Because this membranous structure is observed only after posterior vitreous detachment, the results of this study indicate that it forms part of the internal limiting membrane when the vitreous is in its attached state

Algorithm for numerical integration of the rigid-body equations of motion

A new algorithm for numerical integration of the rigid-body equations of motion is proposed. The algorithm uses the leapfrog scheme and the quantities involved are angular velocities and orientational variables which can be expressed in terms of either principal axes or quaternions. Due to specific features of the algorithm, orthonormality and unit norms of the orientational variables are integrals of motion, despite an approximate character of the produced trajectories. It is shown that the method presented appears to be the most efficient among all known algorithms of such a kind.Comment: 4 pages, 1 figur

Distinctive effects of eicosapentaenoic and docosahexaenoic acids in regulating neural stem cell fate are mediated via endocannabinoid signalling pathways

Emerging evidence suggests a complex interplay between the endocannabinoid system, omega-3 fatty acids and the immune system in the promotion of brain self-repair. However, it is unknown if all omega-3 fatty acids elicit similar effects on adult neurogenesis and if such effects are mediated or regulated by interactions with the endocannabinoid system. This study investigated the effects of DHA and EPA on neural stem cell (NSC) fate and the role of the endocannabinoid signalling pathways in these effects. EPA, but not DHA, significantly increased proliferation of NSCs compared to controls, an effect associated with enhanced levels of the endocannabinoid 2-arachidonylglycerol (2-AG) and p-p38 MAPK, effects attenuated by pre-treatment with CB1 (AM251) or CB2 (AM630) receptor antagonists. Furthermore, in NSCs derived from IL-1β deficient mice, EPA significantly decreased proliferation and p-p38 MAPK levels compared to controls, suggesting a key role for IL-1β signalling in the effects observed. Although DHA similarly increased 2-AG levels in wild-type NSCs, there was no concomitant increase in proliferation or p-p38 MAPK activity. In addition, in NSCs from IL-1β deficient mice, DHA significantly increased proliferation without effects on p-P38 MAPK, suggesting effects of DHA are mediated via alternative signalling pathways. These results provide crucial new insights into the divergent effects of EPA and DHA in regulating NSC proliferation and the pathways involved, and highlight the therapeutic potential of their interplay with endocannabinoid signalling in brain repair