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Abstract Background Gastrointestinal (GI) bleeding represents the single most frequent site of anticoagulant-related bleeding. Adverse outcomes after major GI bleeding including mortality are not well characterized and, as a result, may be underappreciated in clinical practice. We aim to conduct a systematic review and meta-analysis of the risk for 30-day all-cause mortality after major GI bleeding among patients receiving DOACs. Methods Electronic databases including MEDLINE, EMBASE, and Cochrane CENTRAL will be systematically searched to identify randomized controlled trials and prospective and retrospective cohort studies reporting 30-day all-cause mortality in adults with DOAC-related major GI bleeding. At least two investigators will independently perform study selection, risk of bias assessment, and data extraction. The proportion of deaths following a major GI event relative to the number of major GI bleeding events will be calculated for each individual study, and results across studies will be pooled using random-effects meta-analysis. We will assess risk of bias using criteria proposed by the GRADE group for prognostic studies. Discussion The findings of this systematic review and meta-analysis will provide clinicians and patients with estimates of mortality after the most common major bleeding event to support shared decision making about anticoagulation management. Trial registration PROSPERO CRD42022295815.

Introduction Deciding whether to stop or extend anticoagulant therapy indefinitely after completing at least 3 months of initial treatment for a first unprovoked venous thromboembolism (VTE) remains a challenge for clinicians, patients and policy makers. Guidelines suggest an indefinite duration of anticoagulant therapy in these patients, yet its benefits, harms and costs have not been formally assessed. The aim of this proposed modelling study is to assess the differences in clinical benefits, harms and costs of stopping versus continuing anticoagulant therapy indefinitely for a first unprovoked VTE.Methods and analysis We will develop a probabilistic Markov model, adopting a 1-month cycle length and a lifetime horizon, to estimate life-years, quality-adjusted life-years, costs and the incremental cost-effectiveness ratios for a simulated population of patients with a first unprovoked VTE who will receive indefinite duration of anticoagulant therapy versus a population who will not receive extended treatment after completing 3 months of initial anticoagulant therapy. The economic evaluation will adopt a third-party payer perspective relating to a Canadian publicly funded healthcare system. Estimates for the probability of relevant clinical events will be informed by systematic reviews and meta-analyses, while costs and utility values will be obtained from published Canadian sources. Stratified analyses based on sex, age and site of initial VTE will also be performed to identify subgroups of patients with a first unprovoked VTE in whom continuing anticoagulant therapy indefinitely might prove to be clinically beneficial and cost-effective over stopping treatment. We will also conduct sensitivity and scenario analyses to assess robustness of study findings to changes in individual or groups of key parameters.Ethics and dissemination Ethical approval is not applicable for this study. The results will be disseminated through presentations at relevant conferences and in a manuscript that will be submitted to a peer-reviewed journal.

Abstract Background When a journal receives a duplicate publication, the ability to identify the submitted work as previously published, and reject it, is an assay to publication ethics best practices. The aim of this study was to evaluate how three different types of journals, namely open access (OA) journals, subscription-based journals, and presumed predatory journals, responded to receiving a previously published manuscript for review. Methods We performed a quasi-experimental study in which we submitted a previously published article to a random sample of 602 biomedical journals, roughly 200 journals from each journal type sampled: OA journals, subscription-based journals, and presumed predatory journals. Three hundred and three journals received a Word version in manuscript format, while 299 journals received the formatted publisher’s PDF version of the published article. We then recorded responses to the submission received after approximately 1 month. Responses were reviewed, extracted, and coded in duplicate. Our primary outcome was the rate of rejection of the two types of submitted articles (PDF vs Word) within our three journal types. Results We received correspondence back from 308 (51.1%) journals within our study timeline (32 days); (N = 46 predatory journals, N = 127 OA journals, N = 135 subscription-based journals). Of the journals that responded, 153 received the Word version of the paper, while 155 received the PDF version. Four journals (1.3%) accepted our paper, 291 (94.5%) journals rejected the paper, and 13 (4.2%) requested a revision. A chi-square test looking at journal type, and submission type, was significant (χ 2 (4) = 23.50, p

Abstract Background The optimal duration of anticoagulation after a first unprovoked venous thromboembolism (VTE) remains controversial. Deciding to stop or continue anticoagulant therapy indefinitely after completing 3 to 6 months of initial treatment requires balancing the long-term risk of recurrent VTE if anticoagulation is stopped against the long-term risk of major bleeding if anticoagulation is continued. However, knowledge of the long-term risk for major bleeding events during extended anticoagulation in this patient population is limited. We plan to conduct a systematic review and meta-analysis to quantify the risk for major bleeding events during extended oral anticoagulation in patients with first unprovoked VTE. Methods Electronic databases including MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials will be systematically searched with the assistance of an information specialist (from inception to March 1, 2019) to identify randomized controlled trials and prospective cohort studies reporting major bleeding during extended oral anticoagulation in patients with first unprovoked VTE, who have completed at least 3 months of initial anticoagulant therapy. Study selection, risk of bias assessment, and data extraction will be performed independently by at least two investigators. The number of major bleeding events and person-years of follow-up will be used to calculate the rate (events per 100 person-years) with its 95% confidence interval for each study cohort, during clinically relevant time periods of extended anticoagulant therapy. Results will be pooled using random effect meta-analysis. Discussion The planned systematic review and meta-analysis will provide reliable estimates of the risk for major bleeding events during extended anticoagulation. This information will help inform patient prognosis and assist clinicians with balancing the risks and benefits of treatment to guide management of unprovoked VTE. Systematic review registration PROSPERO CRD42019128597.

IntroductionTo summarize and compare the effectiveness of pharmacological thromboprophylaxis to pneumatic compression devices (PCD) for the prevention of venous thromboembolism in patients with acute intracerebral hemorrhage.MethodsMEDLINE, PUBMED, EMBASE, and CENTRAL were systematically searched to identify randomized and non-randomized studies that compared each intervention directly to each other or against a common control (hydration, anti-platelet agents, stockings) in adults with acute spontaneous intracerebral hemorrhage. Two investigators independently screened the studies, extracted data, and appraised risk of bias. Studies with a high risk of bias were excluded from our final analysis. The primary outcome was the occurrence of venous thromboembolism (proximal deep vein thrombosis or pulmonary embolism) in the first 30 days.Results8,739 articles were screened; four articles, all randomized control trials, met eligibility criteria. Bayesian network meta-analysis was performed to calculate risk estimates using both fixed and random effects analyses. 607 patients were included in the network analysis. PCD were associated with a significant decrease in venous thromboembolism compared to control (OR: 0.43, 95% Credible Limits [CrI]: 0.23-0.80). We did not find evidence of statistically significant differences between pharmacological thromboprophylaxis and control (OR: 0.93, 95% CrI: 0.19-4.37) or between PCD and pharmacological thromboprophylaxis (OR: 0.47, 95% CrI: 0.09-2.54).ConclusionPCDs are superior to control interventions, but meaningful comparisons with pharmacotherapy are not possible due to a lack of data. This requires further exploration via large pragmatic clinical trials.Trial registrationPROSPERO: CRD42018090960.

Dr. Benjamin Hibbert, MD, PhD, FRCPC is an interventional cardiologist, an assistant professor, as well as the director of the Vascular Biology and Experimental Medicine Laboratory at the University of Ottawa Heart Institute (UOHI). With a focus on performing revolutionary bench-to-bedside research, Dr. Hibbert’s clinical and basic science research interests include the development of novel cardiac biomarkers, elucidating the mechanisms that underlie pathological arterial remodelling in transplant vasculopathy, and the pharmacodynamics of adjuvant antiplatelet and antithrombotic agents in cardiac disease. We had the privilege of speaking with Dr. Hibbert about his career path, research experiences, and perspectives on the importance of the clinician-investigator program in training the oncoming generation of clinician-scientists.

Endometrial serous carcinomas are very clinically aggressive, which constitutes 40% of all deaths and recurrences associated with endometrial cancer. Small-cell carcinoma of the endometrium is relatively rare but aggressive, and often presents a component of endometrioid carcinoma, and is not generally associated with serous carcinoma. Herein, we report a case of 74-year-old African-American female, who presented with intermittent post-menopausal bleeding for >1-month. She underwent robotic-assisted laparoscopic hysterectomy, bilateral salpingo-oophorectomy, sentinel lymph node mapping, and pelvic-and-aortic lymphadenectomy. Final pathology was consistent with serous carcinoma of the endometrium in combination with neuroendocrine small-cell carcinoma. This extremely rare combination of tumors presents a challenge for treatment. The mainstay of treatment seems to be surgery followed by chemotherapy ± radiation therapy. To our knowledge, it represents an under-reported area of gynecological medicine.

Abstract The escalation in open-access publishing has fueled the rise of questionable businesses, namely, ‘predatory’ journals. Predatory journals and their publishers seek manuscripts through aggressive electronic solicitation and execute flawed peer-review practices, consequently undermining the scholarly record and current research cultures, globally. As these journals are not indexed in any legitimate databases, the research they publish is often undiscoverable and fails to be disseminated to a worldwide readership. Acknowledging this threat to the credibility of science, this article aims to alert researchers at various levels of their career of the increasing global issue of predatory journals, and offer helpful advice and resources for identifying and avoiding them. Résumé L’essor de la publication en accès libre a alimenté l’expansion d’entreprises douteuses, à savoir des revues « prédatrices ». Les revues prédatrices et leurs éditeurs recherchent des manuscrits au moyen de requêtes électroniques agressives et effectuent des évaluations erronées par les pairs, compromettant ainsi les archives scientifiques et les présentes cultures de recherche dans l’ensemble. Puisque ces revues ne sont pas répertoriées dans des bases de données légitimes, la recherche qu’elles publient est souvent introuvable et ne parvient pas à être diffusée à un lectorat mondial. En reconnaissant cette menace à la crédibilité scientifique, cet article vise à alerter les chercheurs à diverses étapes de leur carrière du problème global croissant que constituent les revues prédatrices, et à leur offrir des conseils utiles et des ressources permettant de les identifier et de les éviter.

ABSTRACT: Dr. Dar Dowlatshahi, MD/PhD, is a stroke neurologist, an assistant professor at the University of Ottawa, and a neuroscientist at the Ottawa Hospital Research Institute (OHRI). As the Scientific Director of the Ottawa Stroke Program, he is conducting cutting-edge research in the area of acute stroke, with a special interest in intracerebral hemorrhage (ICH). He was part of the recent ESCAPE trial, a national groundbreaking study that has redefined the scope of stroke therapy around the world. We had the incredible opportunity of speaking with Dr. Dowlatshahi about his exciting career as a clinician-scientist, as he educated us about the unique features of stroke, informed us of the recent advancements in his research, and provided advice for interested students and trainees who want to pursue a career in academic medicine. RÉSUMÉ: Dr. Dar Dowlatshahi, MD/PhD, est un neurologue spécialisé en AVC, professeur adjoint à l’Université d’Ottawa, et un neuroscientifique à l’Institut de recherche en santé d’Ottawa (IRSO). Comme directeur scientifique du Programme d’AVC à Ottawa, il mène des recherches de pointe dans le domaine de l’AVC aigu, avec un intérêt particulier dans l’hémorragie intracérébrale (HIC). Il a fait partie de l’essai récent « ESCAPE », une étude révolutionnaire nationale qui a redéfini le cadre de la thérapie de l’AVC autour du monde. Nous avons eu l’incroyable opportunité de parler avec le Dr. Dowlatshahi à propos de sa carrière passionnante comme clinicien-chercheur. Il nous informa ainsi sur les caractéristiques uniques de l’AVC, des récents progrès dans ses recherches, et nous a fourni des conseils pour les étudiants et stagiaires voulant poursuivre une carrière en médecine académique.

Transverse sinus stenosis (TSS) is often observed in patients with idiopathic intracranial hypertension (IIH). Studies show that all symptoms of IIH can be resolved by transverse sinus stent placement. We present a case of a 39-year-old woman diagnosed with IIH presented with papilledema and severe headaches. The consideration of interventional management was necessitated by the preceding failure of several months of medical treatment. Her vascular imaging demonstrated stenosis of the transverse sinus and her intracranial venous pressure measurements indicated elevated pressure with a high pressure gradient across the stenosis. She underwent transverse sinus stent placement across the stenotic segment. After this intervention, her symptoms improved and her intracranial pressure normalized. The imaging follow-up revealed efficacious patency of the stent. Based on a mathematical model, we suggest that a Starling-like resistor demonstrating a collapsible transverse sinus can permanently be replaced by a rigid-walled sinus upon employment of an endovascular stent in the stenotic transverse sinus, which should be considered as an alternative to other surgical procedures for IIH patients.

Load balancing to alleviate network congestion remains a critical challenge in Vehicular Ad Hoc Networks (VANETs). During route and response scheduling, road side units (RSUs) risk being overloaded beyond their calculated capacity. Despite recent advancements like RSU-based load transfer, NP-Hard hierarchical geography routing, RSU-based medium access control (MAC) schemes, simplified clustering, and network activity control, a significant gap persists in employing a load-balancing server for effective traffic management. We propose a server-based network congestion handling mechanism (SBNC) in VANETs to bridge this gap. Our approach clusters RSUs within specified ranges and incorporates dedicated load balancing and network scheduler RSUs to manage route selection and request–response scheduling, thereby balancing RSU loads. We introduce three key algorithms: optimal placement of dedicated RSUs, a scheduling policy for packets/data/requests/responses, and a congestion control algorithm for load balancing. Using the VanetMobiSim library of Network Simulator-2 (NS-2), we evaluate our approach based on residual energy consumption, end-to-end delay, packet delivery ratio (PDR), and control packet overhead. Results indicate substantial improvements in load balancing through our proposed server-based approach.

Lane level traffic data such as average waiting time and flow data at each turn direction not only enable navigation systems to provide users with more detailed and finer-grained information; it can also pave the way for future traffic congestion prediction. Although few studies considered extracting traffic flow data from a video at the lane level, it is not clear how many vehicles required turn left in fine-grained lanes during a fixed time. Many previous works focus on applying sensor data instead to videos to extract traffic flow. However, the reversible lanes and various shooting angles obstruct the progress of constructing a traffic data collection system. A framework is proposed to get these data in the intersection directly from a video and solve the problem of vehicle occlusion based on the delayed matching model. First, the different direction lanes are detected automatically by clustering trajectory data which are generated by tracking each vehicle. Experiments are conducted on urban intersections to show that our method can generate these traffic data effectively.