14 research outputs found

    The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

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    INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

    Selective versus non Selective Cyclooxygenase Inhibitors in High Fructose-Induced Metabolic Syndrome

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    Metabolic syndrome (MS) is a cluster of interrelated abnormalities namely obesity, dyslipidemia, hypertension, and insulin resistance. Chronic inflammation with release of inflammatory mediators including cyclooxygenase (COX) enzymes represents an important pathogenic factor in the development of MS. The present study investigated the effect of selective COX-2 inhibitor, celecoxib, versus non selective, diclofenac, in prevention of high fructose-induced MS in rats. Rats were divided into 6 groups: normal control (received normal diet); high fructose fed (HF) (received 20% fructose plus saline to serve as control MS group; celecoxib-treated ( received HF plus either celecoxib 10 or 50 mg/kg/day); diclofenac-treated (received HF plus either diclofenac 6 or 30 mg/kg/day). visceral fat index (visceral fat weight /body weight ratio), insulin resistance , serum levels of triglyceride (TG), high density lipoprotein (HDL), malondialdehyde (MDA), reduced glutathione (GSH), catalase, uric acid, C-reactive protein (CRP), and tumor necrosis factor- α (TNF-α) were measured. The results showed that celecoxib, but not diclofenac, prevented the development of high fructose-induced MS as indicated by significant attenuation in visceral fat index, insulin resistance, and lipid profile. The protective effect of celecoxib was associated with significant improvement in serum levels of oxidative stress markers (MDA, GSH, and catalase), and inflammatory markers (uric acid, CRP, and TNF-α). These results indicate that selective COX-2 inhibitors protect against high fructose-induced MS possibly via antioxidant and anti-inflammatory effects

    Students’ performance in interactive environments: an intelligent model

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    Modern approaches in education technology, which make use of advanced resources such as electronic books, infographics, and mobile applications, are progressing to improve education quality and learning levels, especially during the spread of the coronavirus, which resulted in the closure of schools, universities, and all educational facilities. To adapt to new developments, students’ performance must be tracked in order to closely monitor all unfavorable barriers that may affect their academic progress. Educational data mining (EDM) is one of the most popular methods for predicting a student’s performance. It helps monitoring and improving students’ results. Therefore, in the current study, a model has been developed so that students can be informed about the results of the computer networks course in the middle of the second semester and 11 machine algorithms (out of five classes). A questionnaire was used to determine the effectiveness of using infographics for teaching a computer networks course, as the results proved the effectiveness of infographics as a technique for teaching computer networks. The Moodle (Modular Object-Oriented Dynamic Learning Environment) educational platform was used to present the course because of its distinctive characteristics that allow interaction between the student and the teacher, especially during the COVID-19 pandemic. In addition, the different methods of classification in data mining were used to determine the best practices used to predict students’ performance using the weka program, where the results proved the effectiveness of the true positive direction of functions, multilayer perceptron, random forest trees, random tree and supplied test set, f-measure algorithms are the best ways to categories

    Diacerein protects rats with liver ischemia/reperfusion damage: Down-regulation of TLR4/ NFÎş-B signaling pathway

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    Purpose: Liver ischemia-reperfusion (I/R) injury is an inescapable problem. Diacerein, a chondro-protective drug, has antioxidant and anti-inflammatory effects. Its effect on liver I/R injury has not yet been fully clarified. Therefore, the current study aimed to detect its hepatic protective effect with the explanation of possible underlying mechanisms. Methods: Adult male albino rats were assigned to 4 groups: sham group, diacerein pretreated sham group, I/R non-treated group, and I/R diacerein pretreated group. Serum liver enzymes, hepatic tissue oxidative stress parameters, inflammatory biomarkers mainly Toll-like receptors-4 (TLR4), and liver fatty acid binding protein (L-FABP) levels were determined. Histopathological examination of liver tissues and immunohistochemical studies of heat shock protein 70, nuclear factor-kappa B, and Cluster of Differentiation 68 were also done. Results: Diacerein pretreatment has the ability to restore the hepatic I/R damaging effect, proved by the reduction of serum liver enzymes, the decrease of the oxidative stress and hepatic inflammation via down-regulation of TLR4/ NFÎş-B signaling pathway together with the restoration of L-FABP level and improvement of the histopathological and immunohistochemical study findings in the hepatic tissue. Conclusion: These results suggested the hepatoprotective effect of diacerein relies on its antioxidant and anti-inflammatory effects reducing TLR4/ NFÎş-B signaling pathway

    Clinical, Radiological, and Outcome Characteristics of Acute Pulmonary Embolism: A 5-year Experience from an Academic Tertiary Center

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    Background: Acute pulmonary embolism (PE) is a common and potentially life-threatening condition. This comprehensive study from a Gulf Cooperation Council (GCC) country aimed to evaluate the clinical, radiological, and outcome characteristics associated with acute PE. Methods: This retrospective observational study analyzed data of patients with confirmed acute PE who were admitted to the largest academic tertiary center in the State of Qatar from January 1, 2014, to December 31, 2018. Data on the clinical presentation, radiologic, and echocardiographic findings, as well as outcomes were collected. Results: A total of 436 patients were diagnosed with acute PE during the study period (male, 53%). Approximately 56% of the patients were, 50 years old at presentation, with a median age of 47 years. In approximately 69% of cases, the PE occurred outside the hospital. The main associated comorbidities were obesity (34.6%), hypertension (29.4%), and diabetes (25%). Immobilization (25.9%) and recent surgery (20.6%) were the most common risk factors. The most frequent presenting symptom was dyspnea (39.5%), and the most frequent signs were tachycardia (49.8%) and tachypnea (45%). Cardiac arrest was the initial presentation in 2.2% of cases. Chest X-ray findings were normal in 41%. On computed tomography pulmonary angiography (CTPA), 41.3% of the patients had segmental PE, 37.1% had central PE, and 64.1% had bilateral PE. The main electrocardiographic (ECG) abnormality was sinus tachycardia (98%). In patients who underwent echocardiography, right ventricular (RV) enlargement was the main echocardiographic finding (36.4%). Low-, intermediate-, and high-risk PE constituted 49.8%, 31.4%, and 18.8% of the cases, respectively. Thrombolysis was prescribed in 8.3% of the total and 24.4% of the high-risk PE cases. Complications of PE and its treatment (from admission up to 6 months post-discharge) included minor bleeding (14%), major bleeding (5%), PE recurrence (4.8%), and chronic thromboembolic pulmonary hypertension (CTEPH) (5%). A total of 15 (3.4%) patients died from PE. Conclusions: Acute PE can manifest with complex and variable clinical and radiological syndromes. Striking findings in this study are the younger age of acute PE occurrence and the low PE-related mortality rate.The publication of this article was funded by the Medical Research Center at Hamad Medical Corporation

    Abstracts of 1st International Conference on Computational & Applied Physics

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    This book contains the abstracts of the papers presented at the International Conference on Computational & Applied Physics (ICCAP’2021) Organized by the Surfaces, Interfaces and Thin Films Laboratory (LASICOM), Department of Physics, Faculty of Science, University Saad Dahleb Blida 1, Algeria, held on 26–28 September 2021. The Conference had a variety of Plenary Lectures, Oral sessions, and E-Poster Presentations. Conference Title: 1st International Conference on Computational & Applied PhysicsConference Acronym: ICCAP’2021Conference Date: 26–28 September 2021Conference Location: Online (Virtual Conference)Conference Organizer: Surfaces, Interfaces, and Thin Films Laboratory (LASICOM), Department of Physics, Faculty of Science, University Saad Dahleb Blida 1, Algeria
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