Neutron Skins and Halo Orbits in the sd and pf Shells

open3siThe strong dependence of Coulomb energies on nuclear radii makes it possible to extract the latter from calculations of the former. The resulting estimates of neutron skins indicate that two mechanisms are involved. The first one --isovector monopole polarizability—amounts to noting that when a particle is added to a system it drives the radii of neutrons and protons in different directions, tending to equalize the radii of both fluids independently of the neutron excess. This mechanism is well understood and the Duflo- Zuker (small) neutron skin values derived 14 years ago are consistent with recent measures and estimates. The alternative mechanism involves halo orbits whose huge sizes tend to make the neutron skins larger and have a subtle influence on the radial behavior of sd and f shell nuclei. In particular, they account for the sudden rise in the isotope shifts of nuclei beyond N=28 and the near constancy of radii in the A=40–56 region. This mechanism, detected here for the first time, is not well understood and may well go beyond the Efimov physics usually associated with halo orbits.openBonnard, JEREMY CHRISTIAN FREDERIC; Lenzi, SILVIA MONICA; Zuker, A. P.Bonnard, JEREMY CHRISTIAN FREDERIC; Lenzi, SILVIA MONICA; Zuker, A. P

Intravitreal injection of Ozurdex(®) implant in patients with persistent diabetic macular edema, with six-month follow-up

AIM: To evaluate the efficacy of intravitreal dexamethasone injections in diabetic macular edema (DME). METHODS: A 700 μg slow-release intravitreal dexamethasone implant (Ozurdex®) was placed in the vitreal cavity of 17 patients (19 eyes) affected with persistent DME. Best corrected visual acuity (BCVA) was assessed through Early Treatment Diabetic Retinopathy Study (ETDRS). Central macular thickness (CMT) was measured by spectral-domain optical coherence tomography. BCVA and CMT examinations were carried out at baseline (T0) and repeated after three days, one month (T1), three months (T3), four months (T4), and six months (T6) post injection. RESULTS: Dexamethasone implant induced an improvement in ETDRS at T1, T3, T4, and T6 post injection. CMT was reduced at T1, T3, and T4, while at T6, CMT values were not statistically different from baseline. No complications were observed during the follow-up. CONCLUSION: Our data suggest that dexamethasone implant is effective in reducing DME symptoms within a six-month frame

Impairment of the autophagic flux in astrocytes intoxicated by trimethyltin

Autophagy is a lysosomal catabolic route for protein aggregates and damaged organelles which in different stress conditions, such as starvation, generally improves cell survival. An impairment of this degradation pathway has been reported to occur in many neurodegenerative processes. Trimethyltin (TMT) is a potent neurotoxin present as an environmental contaminant causing tremors, seizures and learning impairment in intoxicated subjects. The present data show that in rat primary astrocytes autophagic vesicles (AVs) appeared after few hours of TMT treatment. The analysis of the autophagic flux in TMT-treated astrocytes was consistent with a block of the late stages of autophagy and was accompanied by a progressive accumulation of the microtubule associated protein light chain 3 (LC3) and of p62/SQSTM1. Interestingly, an increased immunoreactivity for p62/SQSTM1 was also observed in hippocampal astrocytes detected in brain slices of TMT-intoxicated rats. The time-lapse recordings of AVs in EGFP-mCherry-LC3B transfected astrocytes demonstrated a reduced mobility of autophagosomes after TMT exposure respect to control cells. The observed block of the autophagic flux cannot be overcome by known autophagy inducers such as rapamycin or 0.5mM lithium. Although ineffective when used at 0.5mM, lithium at higher concentrations (2mM) was able to protect astrocyte cultures from TMT toxicity. This effect correlated well with its ability to determine the phosphorylation/inactivation of glycogen kinase synthase-3β (GSK-3β)

Antinuclear antibodies in COVID 19

We appreciated very much the interesting study by Chang et al. on the presence of antinuclear antibodies (ANAs) in patients with moderate/critical coronavirus disease 2019 (COVID 19). Both we and Chang and collaborators described the presence and significance of ANAs in patients with COVID‐19. The two experiences can be compared because Chang et al. studied a number of cases only slightly larger than us. In our opinion, the most important finding is represented by the presence of the nucleolar ANA reactivity, which, in the study by Chang et al., as in ours, is the most frequently detected among the different ANA patterns. In this regard, it is worth mentioning that the nucleolar ANA pattern is one of the several ANA pattern detectable by Indirect immunofluorescence, together with other patterns, such as speckled, homogenous, multiple nuclear dots, and rim like membranous; this pattern can be the serological marker of systemic sclerosis and its antigenic target is the topoisomerase I protein (or scl70). Interestingly, it is of major relevance to note that among the clinical manifestations of systemic sclerosis, it includes pulmonary involvement in the form of a restrictive syndrome secondary to interstitial pneumopathy resembling COVID‐19 interstitial pneumonia