Binocular vision is a visual property that allows fine discrimination of in-depth distance (stereopsis), as well as enhanced light and contrast sensitivity. In mammals enhanced binocular vision is structurally associated with a large degree of frontal binocular overlap, the presence of a corresponding retinal specialization containing a fovea or an area centralis, and well-developed ipsilateral retinal projections to the lateral thalamus (GLd). We compared these visual traits in two visually active species of the genus Octodon that exhibit contrasting visual habits: the diurnal Octodon degus, and the nocturnal Octodon lunatus. The O. lunatus visual field has a prominent 100° frontal binocular overlap, much larger than the 50° of overlap found in O. degus. Cells in the retinal ganglion cell layer were 40% fewer in O. lunatus (180,000) than in O. degus (300,000). O. lunatus has a poorly developed visual streak, but a well developed area centralis, located centrally near the optic disk (peak density of 4,352 cells/mm2). O. degus has a highly developed visual streak, and an area centralis located more temporally (peak density of 6,384 cells/mm2). The volumes of the contralateral GLd and superior colliculus (SC) are 15% larger in O. degus compared to O. lunatus. However, the ipsilateral projections to GLd and SC are 500% larger in O. lunatus than in O. degus. Other retinorecipient structures related to ocular movements and circadian activity showed no statistical differences between species. Our findings strongly suggest that nocturnal visual behavior leads to an enhancement of the structures associated with binocular vision, at least in the case of these rodents. Expansion of the binocular visual field in nocturnal species may have a beneficial effect in light and contrast sensitivity, but not necessarily in stereopsis. We discuss whether these conclusions can be extended to other mammalian and non-mammalian amniotes.

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Background: The epidemic potential of coronavirus infection is now a reality. Since the first case detected in late 2019 in China, a fast worldwide expansion confirms it. The vascular patient is at a higher risk of developing a severe form of the disease because of its nature associating several comorbid states, and thus, some vascular surgery communities from many countries have tried to stratify patients into those requiring care during these uncertain times. Methods: This is an observational study describing the current daily vascular surgery practice at one tertiary academic hospital in Madrid region, Spaindone of the most affected regions worldwide due to the COVID-19 outbreak. We analyzed our surgical practice since March 14th when the lockdown was declared up to date, May 14th (2 months). Procedural surgical practice, organizational issues, early outcomes, and all the troubles encountered during this new situation are described. Results: Our department is composed of 10 vascular surgeons and 4 trainees. Surgical practice has been reduced to only urgent care, totaling 50 repairs on 45 patients during the period. Five surgeries were performed on 3 COVID-19-positive patients. Sixty percent were due to critical limb ischemia, 45% of them performed by complete endovascular approach, whereas less than 10% of repairs were aorta related. We were allocated to use a total of 5 surgical rooms in different locations, none our usual, as it was converted into an ICU room while performing 50% of those repairs with unusual nursery staff. Conclusions: The COVID-19 outbreak has dramatically changed our organization and practice in favor of urgent or semiurgent surgical care alone. The lack of in-hospital/ICU beds and changing nursery staff changed the whole availability organization at our hospital and was a key factor in surgical decision-making in some cases.

We investigated the protective effect of Trypanosoma rangeli against infection with Trypanosoma cruzi in animal models of various ages and with different doses of inoculum. The age of the mice and the dose of parasites determined the course of the infection. When T. cruzi was inoculated into mice after challenge with T. rangeli, parasitaemia was more controlled, mortality decreased and histopathology showed lower inflammatory infiltration and pseudocysts. This study proposes a new murine model of the protective effect of recombinant proteins of T. rangeli for possible application in the vaccines field.

Recently, a small number of patients have presented with systemic intra-arterial thrombosis and a diagnosis of SARS-CoV-2. There is some evidence to suggest that this may occur, with a small series reporting ischemic strokes in patients in intensive care units. 5 In our experience, patients presenting with limb-threatening ischemia and SARS-CoV-2 have had no other clear reason for development of intra-arterial thrombosis. Management has been dictated primarily by the severity of the organ dysfunction. A conservative approach with the prescription of therapeutic low-molecular-weight-heparin with subsequent conversion to a direct-acting oral anticoagulant has been an effective strategy.Vascular surgeons have to recognize the potential for limb-and life-threatening arterial occlusion events in patients with SARS-CoV-2. Further research is required to try to elucidate the mechanisms by which this disease process activates the coagulation cascade.