Renal Replacement Therapy in Sudan, 2009

Introduction: Despite an early start, the provision of renal replacement therapy (RRT) in Sudan is constrained by economic factors. This report describes the ESRD population and the available renal replacement therapy (RRT) services in Sudan in 2009. Current status: In June 2009, there were 2858 patients on hemodialysis (HD) in Sudan, 122 patients on continuous ambulatory peritoneal dialysis (CAPD), and 1168 kidney transplant recipients. The overall prevalence of treated ESRD was 106 patients per million population. All forms of RRT were funded by the government. The mean age of HD, CAPD and kidney transplant patients was 46±17, 42±22 and 39±13 years respectively. Males constituted 66%, 67.7% and 79.5% and children constituted 3.9%, 25.3% and 6.6% of HD, CAPD and kidney transplant patients respectively. The commonest reported cause of kidney failure was hypertension (26.1%), followed by diabetes mellitus (DM) (10.4%), obstructive uropathy (7.6%), glomerulonephritis (GN) (5.5%), polycystic kidney disease (2.6%), and pyelonephritis (1.1%). The majority of HD patients (83.8%) are offered twice-weekly HD, 83.6% had a functioning arterio-venous (AV) fistula, 6.4% were positive for hepatitis B virus (HBV) infection, 6.5% were positive for hepatitis C virus (HCV) infection, and 0.7% were positive for both HBV and HCV. Target blood pressure, hemoglobin and phosphorus levels were achieved by 26.5%, 23.1% and 28.5% of HD patients compared to 41.8%, 20.6% and 63.5% of CAPD patients respectively. Kidney transplant recipients had their transplant operation performed in Sudan (33.1%), Egypt (20.7%), KSA (18.2%), Jordan (14.8%), Pakistan (8.4%) and other countries. Conclusion: The prevalence of RRT in Sudan remains low. Hypertension and diabetes mellitus are the most commonly reported cause of kidney failure. Keywords: End stage renal disease; Hemodialysis; Kidney transplant; Peritoneal dialysis; Renal replacement therapy; Suda

Towards Optimised FPGA Realisation of Microprogrammed Control Unit Based FIR Filters

Finite impulse response (FIR) filter is one of the most common type of digital filter used in digital signal processing (DSP) applications. An FIR filter is usually realised in hardware using multipliers, adders and registers. Field programmable gate arrays (FPGAs) have been widely explored for the hardware realisation of FIR filters using different algorithms and techniques. One such technique that has recently gained considerable attention is the use of microprogrammed control unit (MPCU) in designing FIR filters. In this chapter, we further explore MPCU technique for optimised hardware realisation of digital FIR filter. To evaluate the performance, two different architectures of FIR filter are designed using Wallace tree multiplier. Both the architectures are coded in Verilog hardware description language (HDL). The performance is analysed by evaluating the resource utilisation and timing reports of Virtex-5 FPGA generated by the Synopsys Synplify Pro tool. Based on the implementation results, as compared to conventional design, Wallace tree multiplier using carry skip adder (CSKA) provides optimal digital FIR filter

The Brain Microvascular Endothelium Supports T Cell Proliferation and Has Potential for Alloantigen Presentation

Endothelial cells (EC) form the inner lining of blood vessels and are positioned between circulating lymphocytes and tissues. Hypotheses have formed that EC may act as antigen presenting cells based on the intimate interactions with T cells, which are seen in diseases like multiple sclerosis, cerebral malaria (CM) and viral neuropathologies. Here, we investigated how human brain microvascular EC (HBEC) interact with and support the proliferation of T cells. We found HBEC to express MHC II, CD40 and ICOSL, key molecules for antigen presentation and co-stimulation and to take up fluorescently labeled antigens via macropinocytosis. In co-cultures, we showed that HBEC support and promote the proliferation of CD4+ and CD8+ T cells, which both are key in CM pathogenesis, particularly following T cell receptor activation and co-stimulation. Our findings provide novel evidence that HBEC can trigger T cell activation, thereby providing a novel mechanism for neuroimmunological complications of infectious diseases. © 2013 Wheway et al

Additive noise effects in active nonlinear spatially extended systems

We examine the effects of pure additive noise on spatially extended systems with quadratic nonlinearities. We develop a general multiscale theory for such systems and apply it to the Kuramoto-Sivashinsky equation as a case study. We first focus on a regime close to the instability onset (primary bifurcation), where the system can be described by a single dominant mode. We show analytically that the resulting noise in the equation describing the amplitude of the dominant mode largely depends on the nature of the stochastic forcing. For a highly degenerate noise, in the sense that it is acting on the first stable mode only, the amplitude equation is dominated by a pure multiplicative noise, which in turn induces the dominant mode to undergo several critical state transitions and complex phenomena, including intermittency and stabilisation, as the noise strength is increased. The intermittent behaviour is characterised by a power-law probability density and the corresponding critical exponent is calculated rigorously by making use of the first-passage properties of the amplitude equation. On the other hand, when the noise is acting on the whole subspace of stable modes, the multiplicative noise is corrected by an additive-like term, with the eventual loss of any stabilised state. We also show that the stochastic forcing has no effect on the dominant mode dynamics when it is acting on the second stable mode. Finally, in a regime which is relatively far from the instability onset, so that there are two unstable modes, we observe numerically that when the noise is acting on the first stable mode, both dominant modes show noise-induced complex phenomena similar to the single-mode case

OHMI: The Ontology of Host-Microbiome Interactions

Host-microbiome interactions (HMIs) are critical for the modulation of biological processes and are associated with several diseases, and extensive HMI studies have generated large amounts of data. We propose that the logical representation of the knowledge derived from these data and the standardized representation of experimental variables and processes can foster integration of data and reproducibility of experiments and thereby further HMI knowledge discovery. A community-based Ontology of Host-Microbiome Interactions (OHMI) was developed following the OBO Foundry principles. OHMI leverages established ontologies to create logically structured representations of microbiomes, microbial taxonomy, host species, host anatomical entities, and HMIs under different conditions and associated study protocols and types of data analysis and experimental results

Prevalence and Correlates of Depressive Symptoms among Medical Students: a Crosssectional Single-centre Study

Background: Depressive symptoms are common among medical students. The aim of the present study was to determine the prevalence and risk factors of depressive symptoms among medical students in Sultan Qaboos University in Oman. Method: A cross-sectional study was conducted among a random sample selected from 1041 medical students at Sultan Qaboos University, Oman. The Patient Health Questionnaire-9 (PHQ-9) was used to screen for depressive symptoms. A logistic regression model was used to determine risk factors for depressive symptoms. Results: Of 197 medical students selected, 189 (61 men and 128 women) responded. The PHQ-9 results showed that the prevalence of depressive symptoms was 41.3%. In multivariate analysis, female students were more likely than male students to develop depression (adjusted odds ratio = 2.866, p = 0.004). Medical students with a family history of depression were more likely to develop depression than those without a family history of depression (adjusted odds ratio = 4.150, p = 0.014). Conclusion: Depressive symptoms are common among medical students in Sultan Qaboos University. Risk factors for depressive symptoms are female sex and family history of depression

Rechallenge patients with immune checkpoint inhibitors following severe immune-related adverse events: review of the literature and suggested prophylactic strategy.

Patients with cancer who developed severe, grade 3 or 4 immune-related adverse events (irAEs) during therapy with immune checkpoint inhibitors are at risk for developing severe toxicities again on rechallenge with checkpoint inhibitors. Consequently, medical oncologists and multidisciplinary teams are hesitant to retreat in this scenario, despite the fact that a number of patients may derive clinical benefit from this approach. Balancing such clinical benefit and treatment-related toxicities for each patient is becoming increasingly challenging as more and more patients with cancer are being treated with checkpoint inhibitors. In this manuscript, we provide an extensive overview of the relevant literature on retreatment after toxicity, and suggest prophylactic approaches to minimize the risk of severe irAE following rechallenge with immune checkpoint blockade, since treatment may be lifesaving in a number of occasions