Epstein-Barr virus: clinical and epidemiological revisits and genetic basis of oncogenesis

Epstein-Barr virus (EBV) is classified as a member in the order herpesvirales, family herpesviridae, subfamily gammaherpesvirinae and the genus lymphocytovirus. The virus is an exclusively human pathogen and thus also termed as human herpesvirus 4 (HHV4). It was the first oncogenic virus recognized and has been incriminated in the causation of tumors of both lymphatic and epithelial nature. It was reported in some previous studies that 95% of the population worldwide are serologically positive to the virus. Clinically, EBV primary infection is almost silent, persisting as a life-long asymptomatic latent infection in B cells although it may be responsible for a transient clinical syndrome called infectious mononucleosis. Following reactivation of the virus from latency due to immunocompromised status, EBV was found to be associated with several tumors. EBV linked to oncogenesis as detected in lymphoid tumors such as Burkitt's lymphoma (BL), Hodgkin's disease (HD), post-transplant lymphoproliferative disorders (PTLD) and T-cell lymphomas (e.g. Peripheral T-cell lymphomas; PTCL and Anaplastic large cell lymphomas; ALCL). It is also linked to epithelial tumors such as nasopharyngeal carcinoma (NPC), gastric carcinomas and oral hairy leukoplakia (OHL). In vitro, EBV many studies have demonstrated its ability to transform B cells into lymphoblastoid cell lines (LCLs). Despite these malignancies showing different clinical and epidemiological patterns when studied, genetic studies have suggested that these EBV- associated transformations were characterized generally by low level of virus gene expression with only the latent virus proteins (LVPs) upregulated in both tumors and LCLs. In this review, we summarize some clinical and epidemiological features of EBV- associated tumors. We also discuss how EBV latent genes may lead to oncogenesis in the different clinical malignancie

Previous use of antithrombotic agents reduces mortality and length of hospital stay in patients with high-risk upper gastrointestinal bleeding

Background & Aims: Anti-thrombotic agents are risk factors for upper gastrointestinal bleeding (UGIB). However, few studies have evaluated their effects on patient outcomes. We assessed the effects of anti-thrombotic agents on outcomes of patients with high-risk UGIB. Methods: We performed a prospective study of 619 patients with acute UGIB (defined by hematemesis, coffee-ground vomit or melena) who required intervention and underwent endoscopy at 8 centers in North America, Asia, and Europe, from March 2014 through March 2015. We collected data recorded on use of anti-thrombotic agents, clinical features, and laboratory test results to calculate AIMS65, Glasgow-Blatchford Score, and full Rockall scores. We also collected and analyzed data on co-morbidities, endoscopic findings, blood transfusion, interventional radiology results, surgeries, length of hospital stay, rebleeding, and mortality. Results: Of the 619 patients who required endoscopic therapy, data on use of anti-thrombotic agents was available for 568; 253 of these patients (44%) used anti-thrombotic agents. Compared to patients not taking anti-thrombotic agents, patients treated with anti-thrombotics were older (P < .001), had a higher mean American Society of Anesthesiologists classification score (P < .0001), had a higher mean Rockall score (P < .0001), a higher mean AIMS65 score (P < .0001), and more frequently bled from ulcers (P < .001). There were no differences between groups in sex, systolic blood pressure, level of hemoglobin at hospital admission, frequency of malignancies, Glasgow-Blatchford Score, need for surgery or interventional radiology, number of rebleeding events, or requirement for transfusion. All-cause mortality was lower in patients who took anti-thrombotic drugs (11 deaths, 4%) than in patients who did not (37 deaths, 12%) (P = .002); this was due to lower bleeding-related mortality in patients taking anti-thrombotic drugs (3 deaths, 1%) than in patients who were not (19 deaths, 6%) (P = .003). Patients taking anti-thrombotic drugs had mean hospital stays of 6.9 days (95% CI, 2–23 days) compared to 7.9 days for non-users of anti-thrombotic agents (95% CI, 2–26 days) (P = .04). Conclusions: Despite being older, with higher American Society of Anesthesiologists classification, AIMS65, and Rockall scores, patients who have UGIB that requires endoscopic therapy and take anti-thrombotic drugs have lower mortality due to GI bleeding and shorter hospital stays, with similar rates of rebleeding, surgery, and transfusions, compared with those not taking anti-thrombotic drugs