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Outcomes of the Qatar Transcatheter aortic valve implantation- registry (QATAVI-registry) –first report 24/7/2024
No full textBackgroundTranscatheter aortic valve implantation (TAVI) is a therapeutic modality for high-surgical-risk patients with severe aortic stenosis. This study describes the outcomes of TAVI performed in Qatar. MethodsThe Qatar TAVI registry (QATAVI) was established to report the outcomes of TAVI procedures performed at Hamad Medical Corporation- Heart Hospital between October 2012 and December 2023. Data were collected both prospectively and retrospectively. Results241 patients underwent TAVI, with a mean age of 73 ± 8 years. The device success rate was 98.8 %. In-hospital para-valvular leak (PVL) was as follows; mild 8.3 %, moderate 0.8 %, and severe 0.0 %. At 1-year, PVL was mild 2.9 %, moderate 0.4 %, and severe 0.0 %. At 2 years, 0.4 % had mild PVL, moderate 0.4 %, and severe 0.0 %. The incidence of stroke was 2.1 % during hospitalization, 2.1 % at 1 year, and 1.2 % at 2 years. For myocardial infarction, the in-hospital rate was 0.8 %, at 1 year 3.3 %, and 1.2 % at 2 years. 3.7 % developed heart failure during the hospital stay, 15.4 % at 1 year, and 4.6 % at 2 years. The 30-day mortality rate was 2.0 %, while a 1-year survival rate was 91 %. Among the 1-year mortality, 67 % died from non-cardiovascular causes. ConclusionThe inaugural report of QATAVI demonstrates a success rate that matches international standards, favorable early and late valvular functions, and improved clinical outcomes related to major adverse cardiovascular events. Moreover, the survival rates observed in this cohort align with those reported in global registries, demonstrating the safety and effectiveness of the TAVI procedure in Qatar.This work was partially funded by the Qatar National Research Fund (QNRF), National Priority Research Program (Grant number NPRP13S-0108-200024). Over the last three years, this fund was used to hire research assistants for data entry and study analysis. The Qatar National Library provides Open Access funding
Optimizing Mean Arterial Pressure Targets for Septic Shock Patients With Chronic Hypertension: A Narrative Review
Get PDFBackground and Aims: Septic shock is a serious infection-related condition that has a big effect on public health. To improve organ perfusion and prognosis in septic shock patients with chronic high blood pressure, optimal mean arterial pressure (MAP) targets are needed. This narrative review aims to summarize existing knowledge and factors to determine the most effective MAP targets in septic shock patients with chronic hypertension. Methods: A careful review of relevant literature was conducted to understand the factors that affect MAP targets in septic shock patients with chronic hypertension. Long-term hypertension patients require personalized MAP targets based on age, health conditions, and septic shock severity. Results: five studies were identified in this narrative review. Guidelines suggest 65-75 mmHg for most cases, but higher targets may be beneficial for proper organ perfusion. Continuous hemodynamic monitoring allows dynamic adjustment of MAP targets. Conclusion: It is crucial to implement personalized MAP management strategies to achieve optimal outcomes for patients with chronic hypertension who are experiencing septic shock. However, there is a lack of consensus on optimal MAP targets among patients with chronic hypertension, which may require higher MAP targets to maintain adequate tissue perfusion. An approach that considers each patient's unique characteristics and includes ongoing assessment is critical for achieving the best MAP targets and improving patient prognosis.The publication of this article was funded by Qatar National Library
Model Order Reduction for System with Negative Imaginary property: Structure-Preserving Approach
No full textModel order reduction (MOR) is a set of methods used to simplify the analysis and design of complex dynamical systems by reducing their size and complexity. However, these techniques often struggle to maintain important structural properties of the original system, such as stability, passivity, and negative imaginary (NI) behavior. NI systems are a type of dissipative system commonly found in applications like flexible structure dynamics and nanopositioning systems, where high-order models are often used. This research introduces a novel MOR approach specifically designed for NI systems that preserves the NI property while improving accuracy. The method uses a parameter optimization framework, where the reduced-order model (ROM) is created by systematically adjusting its matrix elements to minimize the difference between the original system and the ROM. To ensure the NI property is maintained, structural constraints are placed on the ROM parameterization. The effectiveness of this new approach is evaluated using several examples of NI systems and compared with current MOR techniques. Results show that the proposed method can significantly reduce model order while successfully preserving the NI property and improving the ROM’s accuracy.The research work was partially supported by QRDI-QNRF grant number AICC03-0530-200033
Did you know? Aging does not compromise the inhibitory influence of the cardiopulmonary baroreceptors on blood pressure during exercise
Get PDFOlder people develop an exaggerated blood pressure (BP) during whole body exercise, which is associated with a higher risk of sudden cardiac death, myocardial infarction, future hypertension, cardiovascular disease, and left ventricular hypertrophy. Since regular exercise is a common mitigating strategy for many health pathologies associated with aging, identification of the underlying mechanisms responsible for the exaggerated BP response is warranted in order to establish effective exercise prescription. Blood pressure, both at rest and exercise, is regulated within a narrow range around a set value (operating point, OP) by the arterial baroreflex (ABR) via modulation of autonomic neural activity to the heart and vasculature. As BP increases during exercise, the ABR is reset in direct relation to the exercise intensity, and regulates the elevated BP around the new OP.2 The resetting of the ABR during exercise is mediated by activation and interaction of central and peripheral signals arising from higher brain centers (central command), exercising skeletal muscles (exercise pressor reflex) and the cardiopulmonary baroreceptors.This study was supported by The DanishHeart Foundation (03\u20101\u20103\u201069A\u201022074).Scopu
Efficacy and safety of daratumumab for the treatment of refractory/relapsed multiple myeloma. A systematic review of meta-analyses
No full textIntroduction: Several meta-analyses (MAs) of the efficacy and safety of daratumumab in refractory/relapsed multiple myeloma (RRMM) exist. They include different types of populations, Daratumumab regimens, and outcomes. Moreover, there is a wide variation in methodological quality and risk of bias. Objective: This study aimed to conduct a systematic review of MAs to summarize the literature on the efficacy and safety profile of daratumumab use in RRMM, and also provide an assessment of the quality and risk of bias of the MAs if sufficient data is available. Methods: The literature databases Pubmed, Embase, Web of Science, and Cochrane were searched since inception. The quality of methodology was assessed by the AMSTAR-2 tool, and the risk of bias was assessed by the ROBIS tool. Results: Eight MAs were included in the SR. Most studies reported ORR and CR improvement by adding daratumumab to the chemotherapy regimen. Five MAs reported improvement in PFS in daratumumab-based regimens compared to non- daratumumab-based regimens. Only two MAs reported molecular response, favoring daratumumab. Dara was associated with adverse drug events (ADEs), including pneumonia and diarrhea. Conflicting evidence regarding hematological ADEs association with daratumumab exists. The overall quality of the studies is poor, but the MAs had a low risk of bias overall. Conclusion: Despite including low-quality MAs, this SR provides a summary that simplifies clinicians' access to efficacy and safety outcomes of daratumumab in RRMM patients. Future studies are required to reduce the uncertainty and produce higher-quality Mas, particularly regarding daratumumab's safety.Scopu
تطبيقات الذكاء الاصطناعي في التسويق والإعلانات
No full textبودكاست "استفهام"، المقدم من كلية الإدارة والاقتصاد بالتعاون مع مكتب التعلم الرقمي والتعليم الإلكتروني في جامعة قطر. في هذه الحلقة، نناقش دور الذكاء الاصطناعي في عالم التسويق، تطوره، وتأثيره على سلوك المستهلك وخصوصيته في العصر الرقمي مع ضيفنا الفاضل د. على العلوان، أستاذ مشارك في التسويق في كلية الإدارة والاقتصاد
Medicinal Phytocompounds as Potential Inhibitors of p300-HIF1? Interaction: A Structure-Based Screening and Molecular Dynamics Simulation Study
Get PDFBackground: Hypoxia plays a key role in cancer progression, mainly by stabilizing and activating hypoxia-inducible factor-1 (HIF-1). For HIF-1 to function under low oxygen conditions, it must interact with the transcriptional coactivator p300, a critical step for promoting cancer cell survival and adaptation in hypoxic environments. Methods: Consequently, we used drug design and molecular simulation techniques to screen phytochemical databases, including traditional Chinese and African medicine sources, for compounds that could disrupt the p300/HIF-1 interaction. Results: In this study, we identified potential compounds with high docking scores such as EA-176920 (−8.719), EA-46881231 (−8.642), SA-31161 (−9.580), SA-5280863 (−8.179), NE-5280362 (−10.287), NE-72276 (−9.017), NA-11210533 (−10.366), NA-11336960 (−7.818), TCM-5281792 (−12.648), and TCM-6441280 (−9.470 kcal/mol) as lead compounds. Furthermore, the compound with the highest docking score from each database (EA-176920, SA-31161, NE-5280362, NA-11210533, and TCM-5281792) was subjected to further analysis. The stable binding affinity of these compounds with p300 was confirmed by Post-simulation binding free energy (−22.0020 kcal/mol, −25.4499 kcal/mol, −32.4530 kcal/mol, −33.9918 kcal/mol, and −57.7755 kcal/mol, respectively) and KD analysis. Moreover, the selected compounds followed the Lipinski rules with favorable ADMET properties like efficient intestinal absorption, high water solubility, and no toxicity. Conclusions: Our findings highlight the potential of natural compounds to target key protein–protein interactions in cancer and lay the groundwork for future in vitro and in vivo studies to explore their therapeutic potential. Specifically, disrupting the p300/HIF-1 interaction could interfere with hypoxia-driven pathways that promote tumor growth, angiogenesis, and metastasis, offering a promising strategy to suppress cancer progression at the molecular level.Funding text 1: The authors acknowledge the support they received from the Qatar University Office of the Vice President for Research and Graduate Studies (VPRSGS) and Qatar University Health (QU Health). The authors also acknowledge the Biomedical Research Center (BRC) for paying the publication fees, APC. ; Funding text 2: This work was supported by Qatar University grant No. QUPD CAS-23-24491. This study is supported via funding from Prince Sattam bin Abdulaziz University project number (PSAU/2025/R/1446). This was partially funded. Qatar University Biomedical Research Center (BRC) covered the publication fees (APC).Scopu
A Game Changer for Resistant Hypertension: The Rise of Aprocitentan
No full textHypertension is a major risk factor for cardiovascular disease (CVD), and a major contributor to global morbidity and mortality. In particular, resistant hypertension (rHTN), defined as blood pressure that remains elevated despite treatment with at least three antihypertensive agents including a diuretic, continues to be a major pharmacotherapeutic challenge. Traditional antihypertensive drugs often fail in patients with rHTN, underscoring the need for novel therapies. This is a brief mini-review of aprocitentan, a new drug that promises a glimmer of hope for rHTN patients. This drug is a dual endothelin (ET) receptor antagonist that blocks both ETA and ETB receptors. Given that these two receptors are critical players in vasotone regulation, antagonizing them, such as by aprocitentan, would be expected to significantly reduce blood pressure in patients with rHTN. Indeed, the PRECISION clinical trial demonstrated aprocitentan's superior effectiveness in reducing blood pressure in resistant patients, and the effects were sustained. Aprocitentan has been recently FDA-approved, marking a major milestone in hypertension management, offering hope for patients with difficult-to-treat hypertension
Global Accessibility Awareness Day (GAAD)
No full textGlobal Accessibility Awareness Day (GAAD) – 15 May 2025
Varicocele repair for severe oligoasthenoteratozoospermia: Scoping review of published guidelines, and systematic review of the literature
No full textBackground: The outcomes of varicocele repair (VR) for severe oligozooasthenoteratozoospermia (OAT) have not been widely examined. Methods: Assessment of outcomes of VR after severe OAT, employing scoping review of published guidelines, and systematic review of literature. The Newcastle-Ottawa scale appraised the quality of included studies. Findings from both reviews were used to identify knowledge gaps and ways to enhance the evidence base. Results: No published guidelines exist specifically on VR for severe OAT. Of 731 articles retrieved, 15 were included, indicating a scarcity of studies appraising the topic. Most included studies exhibited high risk of bias and low-level evidence. Studies focused on basic sperm parameters; fewer examined hormonal/testicular volume changes, or pregnancy/live births. Studies suggested some post-VR sperm parameters improvements but mostly no changes in hormone levels/testicular volume. We identified four knowledge gaps: methodological issues; narrow scope of research and measurement aspects; lack of genetic considerations; and scarce economic/cost-effectiveness appraisals. We propose some precautions, remedies, and research questions to enhance the thin evidence base. Conclusions: VR for severe OAT has potential to improve sperm parameters. Scarcity of studies, high risk of bias, low-level evidence, and other limitations mitigate against drawing solid conclusions. Future research is required.Scopu