Visceral Leishmaniasis Relapse in Southern Sudan (1999–2007): A Retrospective Study of Risk Factors and Trends

Visceral leishmaniasis (kala-azar) caused by Leishmania donovani is spread from person to person by Phlebotomus sandflies. Major epidemics of visceral leishmaniasis have occurred in Southern Sudan during the 20th century. The worst of these killed 100,000 people in the western Upper Nile area of Southern Sudan from 1984–1994, a loss of one-third of the population. Médecins Sans Frontières has treated 40,000 kala-azar patients in Southern Sudan since the late 1980's. In this study we used routinely collected clinical data to investigate why some patients relapse after treatment. We found that patients with severely enlarged spleens (splenomegaly) are more likely to relapse. Patients treated for 17 days with a combination of two drugs (sodium stibogluconate and paromomycin) were more likely to relapse (but less likely to die) than patients treated for 30 days with a single drug (sodium stibogluconate). However, the transition from sodium stibogluconate to the sodium stibogluconate/paromomycin combination as standard treatment between 2001–2003 has not led to a significant increase in visceral leishmaniasis relapse

A human MAP kinase interactome.

Mitogen-activated protein kinase (MAPK) pathways form the backbone of signal transduction in the mammalian cell. Here we applied a systematic experimental and computational approach to map 2,269 interactions between human MAPK-related proteins and other cellular machinery and to assemble these data into functional modules. Multiple lines of evidence including conservation with yeast supported a core network of 641 interactions. Using small interfering RNA knockdowns, we observed that approximately one-third of MAPK-interacting proteins modulated MAPK-mediated signaling. We uncovered the Na-H exchanger NHE1 as a potential MAPK scaffold, found links between HSP90 chaperones and MAPK pathways and identified MUC12 as the human analog to the yeast signaling mucin Msb2. This study makes available a large resource of MAPK interactions and clone libraries, and it illustrates a methodology for probing signaling networks based on functional refinement of experimentally derived protein-interaction maps

Current and Calcium Responses to Local Activation of Axonal NMDA Receptors in Developing Cerebellar Molecular Layer Interneurons

In developing cerebellar molecular layer interneurons (MLIs), NMDA increases spontaneous GABA release. This effect had been attributed to either direct activation of presynaptic NMDA receptors (preNMDARs) or an indirect pathway involving activation of somato-dendritic NMDARs followed by passive spread of somatic depolarization along the axon and activation of axonal voltage dependent Ca2+ channels (VDCCs). Using Ca2+ imaging and electrophysiology, we searched for preNMDARs by uncaging NMDAR agonists either broadly throughout the whole field or locally at specific axonal locations. Releasing either NMDA or glutamate in the presence of NBQX using short laser pulses elicited current transients that were highly sensitive to the location of the spot and restricted to a small number of varicosities. The signal was abolished in the presence of high Mg2+ or by the addition of APV. Similar paradigms yielded restricted Ca2+ transients in interneurons loaded with a Ca2+ indicator. We found that the synaptic effects of NMDA were not inhibited by blocking VDCCs but were impaired in the presence of the ryanodine receptor antagonist dantrolene. Furthermore, in voltage clamped cells, bath applied NMDA triggers Ca2+ elevations and induces neurotransmitter release in the axonal compartment. Our results suggest the existence of preNMDARs in developing MLIs and propose their involvement in the NMDA-evoked increase in GABA release by triggering a Ca2+-induced Ca2+ release process mediated by presynaptic Ca2+ stores. Such a mechanism is likely to exert a crucial role in various forms of Ca2+-mediated synaptic plasticity

Beta-Arrestin Functionally Regulates the Non-Bleaching Pigment Parapinopsin in Lamprey Pineal

The light response of vertebrate visual cells is achieved by light-sensing proteins such as opsin-based pigments as well as signal transduction proteins, including visual arrestin. Previous studies have indicated that the pineal pigment parapinopsin has evolutionally and physiologically important characteristics. Parapinopsin is phylogenetically related to vertebrate visual pigments. However, unlike the photoproduct of the visual pigment rhodopsin, which is unstable, dissociating from its chromophore and bleaching, the parapinopsin photoproduct is stable and does not release its chromophore. Here, we investigated arrestin, which regulates parapinopsin signaling, in the lamprey pineal organ, where parapinopsin and rhodopsin are localized to distinct photoreceptor cells. We found that beta-arrestin, which binds to stimulated G protein-coupled receptors (GPCRs) other than opsin-based pigments, was localized to parapinopsin-containing cells. This result stands in contrast to the localization of visual arrestin in rhodopsin-containing cells. Beta-arrestin bound to cultured cell membranes containing parapinopsin light-dependently and translocated to the outer segments of pineal parapinopsin-containing cells, suggesting that beta-arrestin binds to parapinopsin to arrest parapinopsin signaling. Interestingly, beta-arrestin colocalized with parapinopsin in the granules of the parapinopsin-expressing cell bodies under light illumination. Because beta-arrestin, which is a mediator of clathrin-mediated GPCR internalization, also served as a mediator of parapinopsin internalization in cultured cells, these results suggest that the granules were generated light-dependently by beta-arrestin-mediated internalization of parapinopsins from the outer segments. Therefore, our findings imply that beta-arrestin-mediated internalization is responsible for eliminating the stable photoproduct and restoring cell conditions to the original dark state. Taken together with a previous finding that the bleaching pigment evolved from a non-bleaching pigment, vertebrate visual arrestin may have evolved from a “beta-like” arrestin by losing its clathrin-binding domain and its function as an internalization mediator. Such changes would have followed the evolution of vertebrate visual pigments, which generate unstable photoproducts that independently decay by chromophore dissociation

Serum cytokine and glucose levels as predictors of poststroke fatigue in acute ischemic stroke patients

Fatigue is a common but often overlooked symptom after stroke. This study investigated whether stroke type, infarct volume, and laterality, as well as the levels of various cytokines and other blood components in the acute phase of acute ischemic stroke (AIS), can predict the level of fatigue at 6, 12, and 18 months after its onset. In 45 patients with acute stroke, serum levels of C-reactive protein, hemoglobin, glucose, and 13 cytokines were measured within 72 h of stroke onset. The cytokine measurements were performed using BioPlex XMap technology (Luminex). The acute serum levels of interleukin (IL)-1β and glucose were positively correlated with the score on the Fatigue Severity Scale (FSS) at 6 months after the stroke (r = 0.37, p = 0.015, and r = 0.37, p = 0.017, respectively). The acute serum levels of IL-ra and IL-9 were negatively correlated with FSS score at 12 months after the stroke (r = −0.38, p = 0.013, and r = −0.36, p = 0.019, respectively). The FSS score at 12 months after stroke was significantly lower in patients with radiologically confirmed infarction than in those without such confirmation (p = 0.048). The FSS score at 18 months was not correlated with any of the measured variables. High acute serum levels of glucose and IL-1β, and low IL1-ra and IL-9 may predict fatigue after AIS, indicating that the development of poststroke fatigue can be accounted for by the proinflammatory response associated with AIS. These novel findings support a new cytokine theory of fatigue after stroke. However, more research is needed to validate the results of this study

Delay to celiac disease diagnosis and its implications for health-related quality of life

<p>Abstract</p> <p>Background</p> <p>To determine how the delay in diagnosing celiac disease (CD) has developed during recent decades and how this affects the burden of disease in terms of health-related quality of life (HRQoL), and also to consider differences with respect to sex and age.</p> <p>Methods</p> <p>In collaboration with the Swedish Society for Coeliacs, a questionnaire was sent to 1,560 randomly selected members, divided in equal-sized age- and sex strata, and 1,031 (66%) responded. HRQoL was measured with the EQ-5D descriptive system and was then translated to quality-adjusted life year (QALY) scores. A general population survey was used as comparison.</p> <p>Results</p> <p>The mean delay to diagnosis from the first symptoms was 9.7 years, and from the first doctor visit it was 5.8 years. The delay has been reduced over time for some age groups, but is still quite long. The mean QALY score during the year prior to initiated treatment was 0.66; it improved after diagnosis and treatment to 0.86, and was then better than that of a general population (0.79).</p> <p>Conclusions</p> <p>The delay from first symptoms to CD diagnosis is unacceptably long for many persons. Untreated CD results in poor HRQoL, which improves to the level of the general population if diagnosed and treated. By shortening the diagnostic delay it is possible to reduce this unnecessary burden of disease. Increased awareness of CD as a common health problem is needed, and active case finding should be intensified. Mass screening for CD might be an option in the future.</p

The α1-adrenergic receptors: diversity of signaling networks and regulation

The α1-adrenergic receptor (AR) subtypes (α1a, α1b, and α1d) mediate several physiological effects of epinephrineand norepinephrine. Despite several studies in recombinant systems and insightfrom genetically modified mice, our understanding of the physiological relevance and specificity of the α1-AR subtypes is still limited. Constitutive activity and receptor oligomerization have emerged as potential features regulating receptor function. Another recent paradigm is that βarrestins and G protein-coupled receptors themselves can act as scaffolds binding a variety of proteins and this can result in growing complexity of the receptor-mediated cellular effects. The aim of this review is to summarize our current knowledge on some recently identified functional paradigms and signaling networks that might help to elucidate the functional diversity of the α1-AR subtypes in various organs

Integrating organizational, social, and individual perspectives in Web 2.0-based workplace e-learning

From the issue entitled 'Special Issue: Emerging Social and Legal Aspect'E-learning is emerging as a popular approach of education in the workplace by virtue of its flexibility to access, just-in-time delivery, and cost-effectiveness. To improve social interaction and knowledge sharing in e-learning, Web 2.0 is increasingly utilized and integrated with e-learning applications. However, existing social learning systems fail to align learning with organizational goals and individual needs in a systemic way. The dominance of technology-oriented approaches makes elearning applications less goal-effective and poor in quality and design. To solve the problem, we address the requirement of integrating organizational, social, and individual perspectives in the development of Web 2.0 elearning systems. To fulfill the requirement, a key performance indicator (KPI)-oriented approach is presented in this study. By integrating a KPI model with Web 2.0 technologies, our approach is able to: 1) set up organizational goals and link the goals with expertise required for individuals; 2) build a knowledge network by linking learning resources to a set of competences to be developed and a group of people who learn and contribute to the knowledge network through knowledge creation, sharing, and peer evaluation; and 3) improve social networking and knowledge sharing by identifying each individual's work context, expertise, learning need, performance, and contribution. The mechanism of the approach is explored and elaborated with conceptual frameworks and implementation technologies. A prototype system for Web 2.0 e-learning has been developed to demonstrate the effectiveness of the approach. © Springer Science + Business Media, LLC 2009.postprin