Particle motion in a rotating dust spacetime: the Bonnor solution

We investigate the geometrical properties, spectral classification, geodesics, and causal structure of the Bonnor's spacetime [Journal of Physics A Math. Gen., \textbf{10}, 1673 (1977)], i.e., a stationary axisymmetric solution with a rotating dust as a source. This spacetime has a directional singularity at the origin of the coordinates (related to the diverging vorticity field of the fluid there), which is surrounded by a toroidal region where closed timelike curves (CTCs) are allowed, leading to chronology violations. We use the effective potential approach to provide a classification of the different kind of orbits on the symmetry plane as well as to study the motion parallel to the symmetry axis. In the former case we find that as a general feature test particles released from a fixed space point and directed towards the singularity are repelled and scattered back as soon as they approach the CTC boundary, without reaching the central singularity.Comment: 11 pages, 5 figures (10 eps files

Development of an Oral IgA Response against SARS-CoV-2 Following Immunization with Different COVID-19 Vaccines

The mucosal immune response is recognized to be important in the early control of infection sustained by viruses with mucosal tissues as the primary site of entry and replication, such as SARS-CoV-2. Mucosal IgA has been consistently reported in the mouth and eye of SARS-CoV-2 infected subjects, where it correlated inversely with COVID-19 symptom severity. Yet, there is still scarce information on the comparative ability of the diverse SARS-CoV-2 vaccines to induce local IgA responses at the virus entry site. Thus, the aim of this study was to assess the presence of anti-SARS-CoV-2 IgA in the saliva of 95 subjects vaccinated with a booster dose and different combinations of vaccines, including mRNA-1273 (Moderna), BNT162b2 (Pfizer-BioNTech), and Vaxzevria (AstraZeneca). The results showed the presence of a mucosal response in 93.7% of vaccinated subjects, with a mean IgA titer of 351.5 ± 31.77 U/mL, strongly correlating with the serum anti-SARS-CoV-2 IgG titer (p < 0.0001). No statistically significant differences emerged between the vaccine types, although the salivary IgA titer appeared slightly higher after receiving a booster dose of the mRNA-1273 vaccine (Moderna) following two doses of BNT162b2 (Pfizer-BioNTech), compared to the other vaccine combinations. These data confirm what was previously reported at the eye level and suggest that monitoring salivary IgA may be a useful tool for driving forward vaccine design and surveillance strategies, potentially leading to novel routes of vaccine administration and boosting

Prognostic value of new left atrial volume index severity partition cutoffs after cardiac rehabilitation program in patients undergoing cardiac surgery

Background: Previous studies showed that left atrial enlargement is an independent marker of adverse outcomes in both primary and secondary cardiovascular prevention. However, no data are available on long-term outcomes in patients undergoing valve surgery and/or coronary artery by-pass graft (CABG) surgery. Aim of the study was to evaluate long-term prognostic role of left atrial volume index (LAVi) after cardiac surgery, using the cutoff values recently proposed by the European Association of Cardiovascular Imaging and American Society of Echocardiography. Methods: We created a retrospective registry of 1703 consecutive patients who underwent cardiovascular rehabilitation program after cardiac surgery, including CABG, valve surgery and valve + CABG surgery. LAVi was calculated as ratio of left atrium volume to body surface area, in ml/m2 at discharge; 563 patients with available LAVi data were included in the study. Results: In the whole population LAVi was 36 ± 14 ml/m2 (mean ± SD) and the follow-up time was 5 ± 1. 5 years. Increased LAVi (>34 ml/m2) predicted major adverse cardiovascular and cerebrovascular events (MACCEs) (HR = 2.1; CI95 %: 1.4–3.1; p < 0.001) and cardiovascular mortality (HR = 2.2; CI95 %: 1.0–4.5; p = 0.032). An increased LAVi remained MACCEs predictor after adjustement for age, gender, diabetes, atrial fibrillation at discharge, echocardiographic E/A ratio and left ventricular ejection fraction (HR = 1.8; CI95 %: 1.0–3.0; p = 0. 036). When the study population was split according to increasing LAVi values, left atrium enlargement resulted a predictor of progressively worse adverse outcome. Conclusions: LAVi is a predictor of long-term adverse cardiovascular outcome after cardiac surgery, even after correction for main clinical and echocardiographic variables. The recently recommended LAVi severity cutoffs appear adequate to effectively stratify outcome in patients undergoing rehabilitation after cardiac surgery

Enlarged vascular foramina and lytic lesions in vertebral bodies: a diagnostic dilemma

Among the skeletal material from the sites of Alghero, Mesumundu and Sant’Antioco di Bisarcio (Sassari, Sardinia) and dated back to the period comprises between the 13th and the late 16th century 5 subadult individuals aged between 5 and 15 years and a mature male showed peculiar osteolytic phenomena of the vertebral bodies. These lesions have the appearance of enlarged vascular foramina, affecting several vertebrae mainly of the thoracic and lumbar spine, sometimes with involvement of the sacrum; on the same vertebral body several lesions are generally visible. In the literature similar features have been attributed to brucellosis or tuberculosis. As for the Sardinian skeletal material, an imaging study on the vertebrae of the adult individual was carried out in order to evaluate the appearance of the lesions within the body. Computed Tomography evidenced internal irregular elongated cavitations, sometimes joined together; erosive rounded lesions, whose presence is not detectable externally, were also showed. The molecular analysis has so far been performed on the subadult from Sant’Antioco di Bisarcio, but at initial analysis the DNA resulted degraded. Therefore, the nature of these lesions remains unclear, as it is not sure if they should be referred to tuberculosis, brucellosis or other pathological conditions [hemolytic anemias (eg. Thalassemia), lymphomas, multiple myeloma and infection by Echinococcus]. Further molecular analyses will be carried out on the remains belonging to the other five individuals in an attempt to clarify the etiology of the above mentioned lesions

Red blood cell distribution width as a novel prognostic marker after myocardial revascularization or cardiac valve surgery

The red blood cell distribution width (RDW) measures the variability in the size of circulating erythrocytes. Previous studies suggested a powerful correlation between RDW obtained from a standard complete blood count and cardiovascular diseases in both primary and secondary cardiovascular prevention. The current study aimed to evaluate the prognostic role of RDW in patients undergoing cardiac rehabilitation after myocardial revascularization and/or cardiac valve surgery. The study included 1.031 patients with available RDW levels, prospectively followed for a mean of 4.5 +/- 3.5 years. The mean age was 68 +/- 12 years, the mean RDW was 14.7 +/- 1.8%; 492 patients (48%) underwent cardiac rehabilitation after myocardial revascularization, 371 (36%) after cardiac valve surgery, 102 (10%) after valve-plus-coronary artery by-pass graft surgery, 66 (6%) for other indications. Kaplan-Meier analysis and Cox hazard analysis were used to associate RDW with mortality. Kaplan-Meier analysis demonstrated worse survival curves free from overall (log-rank p&lt;0.0001) and cardiovascular (log-rank p&lt;0.0001) mortality in the highest RDW tertile. Cox analysis showed RDW levels correlated significantly with the probability of overall (HR 1.26; 95% CI 1.19-1.32; p&lt;0.001) and cardiovascular (HR 1.31; 95% CI 1.23-1.40; p&lt;0.001) mortality. After multiple adjustments for cardiovascular risk factors, hemoglobin, hematocrit, C-reactive protein, microalbuminuria, atrial fibrillation, glomerular filtration rate,left ventricular ejection fraction and number of exercise training sessions attended, the increased risk of overall (HR 1.10; 95% CI 1.01-1.27; p=0.039) and cardiovascular (HR 1.13; 95% CI 1.01-1.34; p=0.036)mortality with increasing RDW values remained significant. The RDW represents an independent predictor of overall and cardiovascular mortality in secondary cardiovascular prevention patients undergoing cardiac rehabilitation

347 From arterial hypertension to left ventricular hypertrophy and heart failure: role of cardiopulmonary exercise testing in heart failure with preserved ejection fraction

Abstract Aims Arterial hypertension (AHT) represents the leading cause of heart failure (HF). A complex cardiovascular (CV) continuum of events leads to the progression from AHT to left ventricular hypertrophy (LVH), the hallmark of hypertensive heart (HH), towards heart failure with preserved ejection fraction (HFpEF) or reduced ejection fraction (HFrEF). Cardiopulmonary exercise testing (CPET) represents an important tool to evaluate HF patients (both with HFpEF and HFrEF) allowing quantification of functional capacity and mechanisms of dyspnoea as well as providing prognostic markers. To investigate CPET responses in AHT patients at various stages of disease progression from AHT to LVH and HF with preserved and reduced ejection fraction. Methods and results From a CPET registry of 1.397 consecutive subjects, 92 patients were selected (matched according to age, gender, BMI, CV risk factors, beta-blockers) and divided into four groups: 23 AHT patients without LVH, 23 HH patients, 23 HFpEF patients and 23 HFrEF. HFrEF were defined according to LV-EF values while HFpEF were defined according to the presence of NYHA Class ≥2 and HFA-PEFF Score. Mean age was 65 ± 10 years, mean BMI was 28.5 ± 5, male gender was prevalent 83% and 33% had diabetes. Both HFpEF and HFrEF showed lower cardiorespiratory fitness (peak VO2; P &lt; 0.001), cardiovascular efficiency (VO2/Watt slope: P &lt; 0.001), oxygen pulse (VO2/HR: P &lt; 0.001), cardiac output (P &lt; 0.001) and stroke volume (P &lt; 0.001) at peak as well as lower chronotropic response (P &lt; 0.001), ventilatory efficiency (VE/VCO2 slope: P &lt; 0.001), and heart rate recovery (HRR: P = 0.004) compared with both AHT and HH groups. Interestingly, no differences between HFpEF and HFrEF have been found in all CPET data except for chronotropic response (using Tanaka equation), lower in HFpEF (37.5 ± 16.5 vs. 53.5 ± 20.5; P &lt; 0.001) and ventilatory efficiency, lower in HFrEF (VE/VCO2 slope: 32 ± 5 vs. 37 ± 10; P &lt; 0.001). Finally, adding functional capacity (peak VO2) data to ESC Criteria an improvement in HFpEF diagnosis accuracy was found, with 82% sensitivity and 90% specificity (AUC: 859—95% CI: 754–963; P &lt; 0.0001). Conclusions Despite the intrinsic differences in ejection fraction, both HFpEF and HFrEF shares similar cardiopulmonary mechanisms and cardiovascular responses to exercise. CPET may represent a useful tool in order to identify and stratify hypertensive heart patients with HFpEF with high diagnostic accuracy

Measurement of charged particle yields from therapeutic beams in view of the design of an innovative hadrontherapy dose monitor

Particle Therapy (PT) is an emerging technique, which makes use of charged particles to efficiently cure different kinds of solid tumors. The high precision in the hadrons dose deposition requires an accurate monitoring to prevent the risk of under-dosage of the cancer region or of over-dosage of healthy tissues. Monitoring techniques are currently being developed and are based on the detection of particles produced by the beam interaction into the target, in particular: charged particles, result of target and/or projectile fragmentation, prompt photons coming from nucleus de-excitation and back-to-back γ s, produced in the positron annihilation from β + emitters created in the beam interaction with the target. It has been showed that the hadron beam dose release peak can be spatially correlated with the emission pattern of these secondary particles. Here we report about secondary particles production (charged fragments and prompt γ s) performed at different beam and energies that have a particular relevance for PT applications: 12C beam of 80 MeV/u at LNS, 12C beam 220 MeV/u at GSI, and 12C, 4He, 16O beams with energy in the 50–300 MeV/u range at HIT. Finally, a project for a multimodal dose-monitor device exploiting the prompt photons and charged particles emission will be presented

Anxiety disorders and stressful events in Takotsubo syndrome

Background: Anxiety disorders are more common in Takotsubo syndrome (TS) than in acute coronary syndrome patients. The aim of this study was to investigate whether pre-existing anxiety disorders predispose to TS triggered by exclusively emotional stressful events.Methods: Triggering events were compared in 58 TS patients with and without pre-existing anxiety disorders; clinical, electrocardiographic and echocardiographic data were also collected.Results: Thirty-one (53%) patients had a previous history of anxiety disorders. The exclusively emotional stressful event-rate was higher in TS patients with pre-existing anxiety disorder (74% vs. 30%, p = 0.001), while TS caused by an undetermined trigger were significantly higher in patients without anxiety disorders (33% vs. 10%, p = 0.027). Moreover, in TS patients without a previous history of anxiety disorders, a trend of higher prevalence of physical events was found (16% vs. 37%, p = 0.07).Conclusions: In patients with pre-existing anxiety disorders, TS was predominantly triggered by exclusively emotional stressful events, thereby suggesting a possible relationship between anxiety and emotional cardiac frailty in TS patients