The expression of Mas-receptor of the renin-angiotensin system in the human eye

The local renin-angiotensin system has been held to be expressed in many organs, including the eye. It has an important role in the regulation of local fluid homeostasis, cell proliferation, fibrosis, and vascular tone. Mas-receptor (Mas-R) is a potential receptor acting mainly opposite to the well-known angiotensin II receptor type 1. The aim of this study was to determine if Mas-R is expressed in the human eye. Seven enucleated human eyes were used in immunohistochemical detection of Mas-R and its endogenous ligand angiotensin (1-7) [Ang(1-7)]. Both light microscopy and immunofluorescent detection methods were used. A human kidney preparation sample was used as control. The Mas-R was found to have nuclear localization, and localized in the retinal nuclear layers and in the structures of the anterior segment of the eye. A cytoplasmic immunostaining pattern of Ang(1-7) was found in the inner and outer nuclear and plexiform layers of the retina and in the ciliary body. To the best of our knowledge, this is the first report showing Mas-R expression in the human eye. Its localization suggests that it may have a role in physiological and pathological processes in the anterior part of the eye and in the retina.Peer reviewe

Impact of the first response unit on prehospital on-scene time among paramedic-suspected stroke patients : a retrospective before–after cohort study in Finland

Background: Revascularization of an occluded artery by either thrombolysis or mechanical thrombectomy is a time-critical intervention in ischaemic stroke. Each link in the stroke chain of survival should minimize the delay to definitive treatment in every possible way. In this study, we investigated the effect of routine dispatch of a first response unit (FRU) on prehospital on-scene time (OST) on stroke missions. Methods: Medical dispatch of FRU together with an emergency medical service (EMS) ambulance was a routine strategy in the Tampere University Hospital area before 3 October 2018, after which the FRU has only been dispatched to medical emergencies on the decision of an EMS field commander. This study presents a retrospective before–after analysis of 2,228 paramedic-suspected strokes transported by EMSs to Tampere University Hospital. We collected data from EMS medical records from April 2016 to March 2021, and used statistical tests and binary logistic regression to detect the associations between the variables and the shorter and longer half of OSTs. Results: The median OST of stroke missions was 19 min, IQR [14–25] min. The OST decreased when the routine use of the FRU was discontinued (19 [14–26] min vs. 18 [13–24] min, p < 0.001). The median OST with the FRU being the first at the scene (n = 256, 11%) was shorter than in cases where the FRU arrived after the ambulance (16 [12–22] min vs. 19 [15–25] min, p < 0.001). The OST with a stroke dispatch code was shorter than with non-stroke dispatches (18 [13–23] min vs. 22 [15–30] min, p < 0.001). The OST for thrombectomy candidates was shorter than that for thrombolysis candidates (18 [13–23] min vs. 19 [14–25], p = 0.01). The shorter half of OSTs were associated with the FRU arriving first at the scene, stroke dispatch code, thrombectomy transportation and urban location. Conclusion: The routine dispatch of the FRU to stroke missions did not decrease the OST unless the FRU was first to arrive at the scene. In addition, a correct stroke identification in the dispatch centre and thrombectomy candidate status decreased the OST.Peer reviewe