Underground radiobiology: a perspective at Gran Sasso National Laboratory

Scientific community and institutions (e. g., ICRP) consider that the Linear No-Threshold (LNT) model, which extrapolates stochastic risk at low dose/low dose rate from the risk at moderate/high doses, provides a prudent basis for practical purposes of radiological protection. However, biological low dose/dose rate responses that challenge the LNT model have been highlighted and important dowels came from radiobiology studies conducted in Deep Underground Laboratories (DULs). These extreme ultra-low radiation environments are ideal locations to conduct below-background radiobiology experiments, interesting from basic and applied science. The INFN Gran Sasso National Laboratory (LNGS) (Italy) is the site where most of the underground radiobiological data has been collected so far and where the first in vivo underground experiment was carried out using Drosophila melanogaster as model organism. Presently, many DULs around the world have implemented dedicated programs, meetings and proposals. The general message coming from studies conducted in DULs using protozoan, bacteria, mammalian cells and organisms (flies, worms, fishes) is that environmental radiation may trigger biological mechanisms that can increase the capability to cope against stress. However, several issues are still open, among them: the role of the quality of the radiation spectrum in modulating the biological response, the dependence on the biological endpoint and on the model system considered, the overall effect at organism level (detrimental or beneficial). At LNGS, we recently launched the RENOIR experiment aimed at improving knowledge on the environmental radiation spectrum and to investigate the specific role of the gamma component on the biological response of Drosophila melanogaster

A prospective, randomized, comparative study of intravenous alone and combined intravenous and intraarticular administration of tranexamic acid in primary total knee replacement

Background: Studies on the use of tranexamic acid (TXA) to improve clinical outcomes after joint arthroplasty have reported contrasting results between intravenous (IV) TXA alone and combined IV and intraarticular (IA) administration. We compared the effectiveness of the 2 methods in providing higher postoperative hemoglobin (Hb) levels in patients undergoing primary total knee arthroplasty (TKA). Methods: A total of 100 TKA patients were randomly assigned to receive either IV TXA alone (group 1) or combined IV and topical IA TXA (group 2). Hb and hematocrit levels were measured before and after surgery. The amount of drained blood and transfused blood for the 2 groups was compared. Results: The Hb level was significantly higher at postoperative day 4, together with a positive, albeit not significant, trend toward less postoperative blood loss in the group that received combined IV and IA TXA. No postoperative infections or deep venous thrombosis events occurred. Conclusions: This study reinforces evidence that, as compared to IV TXA alone, combined IV and IA administration of TXA has a synergic effect, leading to higher postoperative Hb levels without influencing drug safety in TKA patients. Keywords: Postoperative blood loss, Total knee arthroplasty, Tranexamic acid, Postoperative hemoglobin, Intravenous, Intraarticula

New trends in anterior cruciate ligament reconstruction: A systematic review of national surveys of the last 5 years

The purpose of this study was to analyze national surveys of orthopaedic surgeons on anterior cruciate ligament (ACL) reconstruction to determine their preferences related to the preferred graft, femoral tunnel positioning, fixation and tensioning methods, antibiotic and anti-thromboembolic prophylaxis, and use of tourniquet and drains. A systematic search of PubMed, Web of Science, and Cochrane Library was performed. Inclusion criteria were surveys of ACL reconstruction trends and preferences published in the past 5 years (2011\u20132016), involving members of national societies of orthopaedics. Information regarding survey modalities, population surveyed, graft choice both in the general or in the athletic population, surgical technique, fixation, use of antibiotic, tourniquet, drains, and anti-thromboembolic prophylaxis was extracted. Eight national surveys were included from Europe (three), North or Latin America (three), and Asia (two). Overall, 7,420 questionnaires were sent, and 1,495 participants completed the survey (response rate ranging from 16 to 76.6%). All surveys reported the hamstring tendon (HT) autograft as the preferred graft, ranging from 45 to 89% of the surveyed population, followed by bone-patellar tendon-bone (BPTB) graft (2\u201341%) and allograft (2\u201317%). Only two surveys focusing on graft choice in athletic population underlined how in high-demand sportive population the graft choices changes in favor of BPTB. Single-bundle reconstruction was the preferred surgical technique in the four surveys that investigated this issue. Five surveys were in favor of anteromedial (AM) portal and two in favor of trans-tibial technique. Suspension devices for femoral fixation were the preferred choice in all but one survey, while interference screws were the preferred method for tibial fixation. The two surveys that investigated graft tensioning were in favor of manual tensioning. The use of tourniquet, antibiotics, drains, and anti-thromboembolic prophylaxis were vaguely reported. A trend toward the preference of HT autograft was registered in all the surveys; however, sport participation has been highlighted as an important variable for increased use of BPTB. Single-bundle reconstruction with AM portal technique and suspension femoral