Summing over Spacetime Dimensions in Quantum Gravity

[EN] Quantum-gravity corrections (in the form of a minimal length) to the Feynman propagator for a free scalar particle in R-D are shown to be the result of summing over all dimensions D '>= D of R-D ', each summand taken in the absence of quantum gravityThe research of E.C. was funded by grant CU 338/1-1 from Deutsche Forschungsgemeinschaft (Germany). The research of J.M.I. was supported by grant no. RTI2018-102256-B-I00 (Spain). The authors acknowledge support from Vielberth Stiftung, Regensburg (GermanyCuriel, E.; Finster, F.; Isidro, J. (2020). Summing over Spacetime Dimensions in Quantum Gravity. Symmetry (Basel). 12(1):1-8. https://doi.org/10.3390/sym12010138S1812

Uterine Fibroids: Clinical Presentation

The signs and symptoms of leiomyoma are varied. Most patients with uterine fibroids are asymptomatic and require no treatment. This is especially so in patients with small subserosal and intramural leiomyomas. Such patients may have the leiomyomas discovered incidentally during workup for other medical condition such as pregnancy. Some of them are also incidentally discovered in hysterectomy specimens for other pelvic masses. The common symptoms associated with leiomyomas include menorrhagia, pelvic pain or pressure, and subfertility. These symptoms vary from one patient to another and do not necessarily correlate to the size of the fibroids. Abdomino-pelvic examination may be normal if the fibroids are small. However, findings of a suprapubic mass and tenderness are not an uncommon finding for bigger myomas

Open thoracic or thoracoabdominal aortic aneurysm repair after previous abdominal aortic aneurysm surgery

ObjectiveThe purpose of this study was to provide insight into the incidence of thoracic and thoracoabdominal aortic aneurysm repair following previous infrarenal abdominal aortic aneurysm (AAA) surgery and to determine whether thoracic or thoracoabdominal aortic aneurysm repair after prior infrarenal AAA surgery is associated with higher mortality and morbidity rates.MethodsMEDLINE, Cochrane Library CENTRAL, and EMBASE databases were searched for relevant articles. Selected articles were critically appraised and meta-analyses were performed.ResultsA total of 12.4% of patients with thoracic aortic aneurysms and 18.7% of patients with thoracoabdominal aortic aneurysms have had prior AAA surgery. The chance of developing a thoracic aortic aneurysm in patients with AAA is 2.2% and 2.5% for developing a thoracoabdominal aortic aneurysm. The mean time interval between prior AAA surgery and subsequent thoracoabdominal aortic aneurysm surgery or detection is 8.0 years with a wide variation between individuals. Surgery in these patients is technically feasible. The 30-day mortality of patients undergoing open thoracoabdominal aortic aneurysm repair does not significantly differ from patients without prior AAA surgery and the 30-day mortality is 11.8%. No data were available about mortality of patients with prior AAA repair undergoing thoracic aortic aneurysm surgery. Morbidity risks are higher in patients with thoracic or thoracoabdominal aortic aneurysms. Prior AAA repair was a significant risk factor for neurological deficit after thoracic or thoracoabdominal aortic aneurysms surgery with relative risks (RRs) of 11.1 (95% confidence interval [CI] 3.8-32.3, P value < .0001) and 2.90 (95% CI 1.26-6.65, P value = .008), respectively. Prior AAA repair was a significant risk factor for developing renal failure in patients undergoing thoracoabdominal aortic aneurysm repair (RR 3.47, 95% CI 1.74-6.91, P value = .0001). Determinants of the prognosis in these patients include distal aortic perfusion, distal extent of the landing zone of the graft, drainage of cerebrospinal fluid for thoracic aortic aneurysm repair and age, history of cardiac diseases, extent of the aneurysm, rupture, amount of estimated blood loss, aortic clamp time, and visceral ischemic times for thoracoabdominal aortic aneurysm repair.ConclusionsA considerable group of patients with thoracic or thoracoabdominal aortic aneurysms have had prior AAA repair. The risk of postoperative morbidity is increased in these patients. Mortality appears to be similar for patients with thoracoabdominal aortic aneurysms. Patients with prior AAA repair undergoing thoracic or thoracoabdominal aortic aneurysm repair should be provided maximum care to protect their spinal cord and renal function

Genetic diversity and population structure of three native cattle populations in Mozambique

In the present work, the population diversity and structure of three populations of native Mozambican cattle were studied, to develop knowledge that is required for sound conservation and genetic improvement programs of these genetic resources. A total of 228 animals (Landim, Angone, and Tete) were genotyped using the International Dairy and Beef version three (IDBV3) SNP BeadChip array. Population parameters varied within a limited scope, with the average minor allele frequency (MAF) ranging from 0.228 ± 0.154 in the Angone to 0.245 ± 0.145 in the Tete population, while estimates of expected heterozygosities varied from 0.304 ± 0.166 in the Angone to 0.329 ± 0.148 in the Tete population. Low positive (0.065 ± 0.109) inbreeding rates were detected in the three cattle groups. Population structure and admixture analyses indicated low genetic differentiation and various degrees of admixture among the populations. The effective population size has decreased over time and at 12 generations ago ranged between 349 (Tete) and 929 (Landim). The average linkage disequilibrium (LD) of the studied populations ranged from 0.400 ± 0.213 (Tete) to 0.434 ± 0.232 (Landim). The findings of this study will be valuable for formulating management and conservation strategies for indigenous Mozambican cattle populations.The Ministry of Science, Technology, and Higher Education of Mozambique.http://link.springer.com/journal/11250hj2022Animal and Wildlife Science

Impact of calcium on procedural and clinical outcomes in lesions treated with bioresorbable vascular scaffolds - A prospective BRS registry study

Background: There is limited data on the impact of calcium (Ca) on acute procedural and clinical outcomes in patients with lesions treated with bioresorbable vascular scaffolds (BRS). We sought to evaluate the effect of calcium on procedural and clinical outcomes in a 'real world' population. Methods: Clinical outcomes were compared between patients with at least 1 moderately or heavily calcified lesion (Ca) and patients with no/mild calcified lesions (non-Ca) enrolled in our institutional BRS registry. Results: 455 patients (N) with 548 lesions (L) treated with 735 BRS were studied. Patients in the Ca group (N = 160, L = 200) had more complex (AHA B2/C lesion: 69.0% in Ca vs 14.9% in non-Ca, p. <. 0.001) and significantly longer lesions (27.80. ±. 15.27 vs 19.48. ±. 9.92. mm, p. <. 0.001). Overall device success rate was 99.1% with no significant differences between the groups. Despite more aggressive lesion preparation and postdilation compared to non Ca, acute lumen gain was significantly less in Ca lesions (1.50. ±. 0.66 vs 1.62. ±. 0.69. mm, p = 0.040) with lower final MLD (2.28. ±. 0.41 vs 2.36. ±. 0.43, p = 0.046). There were no significant differences in all-cause mortality, total definite scaffold thrombosis (ST), target lesion revascularization and myocardial infarction between the 2 groups. Late ST was more frequent in the Ca group compared to non Ca group (late ST: 2.1 vs 0%, p = 0.02). Conclusions: Clinical outcomes after BRS implantation in calcified and non-calcified lesions were similar. A remarkable difference in timing of thrombosis was observed, with an increased rate of late thrombosis in calcified lesions

Are BVS suitable for ACS patients? Support from a large single center real live registry

Objectives To investigate one-year outcomes after implantation of a bioresorbable vascular scaffold (BVS) in patients presenting with acute coronary syndrome (ACS) compared to stable angina patients. Background Robust data on the outcome of BVS in the setting of ACS is still scarce. Methods Two investigator initiated, single-center, single-arm BVS registries have been pooled for the purpose of this study, namely the BVS Expand and BVS STEMI registries. Results From September 2012-Octob

One-year efficacy and safety of routine prasugrel in patients with acute coronary syndromes treated with percutaneous coronary intervention

Objective: To investigate 1‑year outcomes with routine prasugrel treatment after acute coronary syndrome (ACS) in a large-scale registry. Methods: The Rijnmond Collective Cardiology Research registry is a prospective, observational study that enrolled 4,258 consecutive ACS patients treated with percutaneous coronary intervention (PCI) with 1‑year follow-up. Patients received prasugrel as first-choice antiplatelet agent, except for increased bleeding risk patients in which clopidogrel was recommended. Events were validated by an independent clinical endpoint committee. Results: A total number of 2,677 patients received prasugrel at discharge after the index event. Eighty-one percent of the target population was on prasugrel treatment at hospital discharge. At 1 year, the primary endpoint, a composite of all-cause mortality and myocardial infarction, occurred in 2.4% of patients receiving prasugrel. All-cause mortality occurred in 1.0%, myocardial infarction in 1.5%, target-vessel revascularisation in 3.1%, stent thrombosis in 0.6%, and stroke in 0.5% of the patients treated with prasugrel. Thrombolysis in Myocardial Infarction defined major bleeding episodes not related to coronary artery bypass grafting were observed in 1.4% of patients receiving prasugrel. Conclusions: In routine practice, a tailored approach of prasugrel prescription in ACS patients undergoing PCI, resulted in low ischaemic and low bleeding rates up to 1 year post PCI

Initial experience with everolimus-eluting bioresorbable vascular scaffolds for treatment of patients presenting with acute myocardial infarction

Aims: Limited data are currently available on midterm outcomes after implantation of everolimus-eluting bioresorbable vascular scaffolds (BVS) for treatment of acute ST-elevation myocardial infarction (STEMI). Methods and results: Patients presenting with STEMI and undergoing primary percutaneous coronary intervention in the initial experience with BVS were evaluated and compared with patients treated with everolimus-eluting metal stents (EES) by applying propensity matching. Quantitative coronary angiography analysis, and 18-month clinical follow-up were reported. A total of 302 patients were analysed, 151 with BVS and 151 with EES. Baseline clinical characteristics were similar between groups. Final TIMI 3 flow was 87.4% vs. 86.1%, p=0.296. At 18-month follow-up, all-cause mortality was 2.8% vs. 3.0% in the BVS and EES groups respectively, p=0.99; the MACE rate was higher in the BVS group (9.8% vs. 3.6%, p=0.02); target lesion revascularisation was 5.7% vs. 1.3%, p=0.05. The 30-day MACE rate in BVS patients without post-dilatation was 6.8%, while in patients with post-dilatation it was 3.6%. Scaffold thrombosis (ST) occurred primarily in the acute phase (acute ST 2.1% vs. 0.7%, p=0.29; subacute 0.7% vs. 0.7%, p=0.99; late 0.0% vs. 0.0%; very late 1.5% vs. 0.0%, p=0.18). All three BVS cases with acute ST had no post-dilatation at the index procedure. Conclusions: STEMI patients treated during the early experience with BVS had similar acute angiographic results as compared with the EES group. Clinical midterm follow-up data showed a higher clinical events rate compared with metal stents. The majority of clinical events occurred in the early phase after implantation and mainly in cases without post-dilatation. Optimisation of the implantation technique in the acute clinical setting is of paramount importance for optimal short and mid-term outcomes