Ly6c as a New Marker of Mouse Blood Vessels: Qualitative and Quantitative Analyses on Intact and Ischemic Retinas

Ly6c is an antigen commonly used to differentiate between classical and non-classical monocytes/macrophages. Here we show its potential as a marker of the mouse vasculature, particularly of the retinal vascular plexuses. Ly6c was immunodetected in several tissues of C57BL/6 mice using isolectin IB4 as the control of vasculature staining. In the retina, Ly6c expression was analyzed qualitatively and quantitatively in intact, ischemic, and contralateral retinas from 0 to 30 days after the insult. Ly6c expression was observed in all organs and tissues tested, with a brighter signal and more homogeneous staining than the IB4. In the retinas, Ly6c was well expressed, allowing a detailed study of their anatomy. The three retinal plexuses were morphologically different, and from the superficial to the deep one occupied 15 ± 2, 24 ± 7, and 38 ± 1.4 percent of the retinal surface, respectively. In the injured retinas, there was extravasation of the classically activated monocyte/macrophages (Ly6chigh) and the formation of new vessels in the superficial plexus, increasing the area occupied by it to 25 ± 1%. In the contralateral retinas, the superficial plexus area decreased gradually, reaching significance at 30 days, and Ly6c expression progressively disappeared in the intermediate and deep plexuses. Although the role of Ly6c in vascular endothelial cell function is still not completely understood, we demonstrate here that Ly6c can be used as a new specific marker of the mouse vasculature and to assess, qualitatively and quantitatively, vascular changes in health and disease.

Optical coherence tomography-angiography in diabetic retinopathy diagnosis and monitoring

Optical coherence tomography-angiography is a modern noninvasive method of 3D imaging and quantitative analysis of the retinal and choroidal microvasculature. It allows detecting manifestation and progression of diabetic retinopathy, planning treatment and evaluating its results.Optical coherence tomography angiography expands our understanding of microvascular changes in retinal vascular plexuses at different disease stages and deepens the understanding of its pathogenesis.

Extracellular Environment-Controlled Angiogenesis, and Potential Application for Peripheral Nerve Regeneration

Endothelial cells acquire different phenotypes to establish functional vascular networks. Vascular endothelial growth factor (VEGF) signaling induces endothelial proliferation, migration, and survival to regulate vascular development, which leads to the construction of a vascular plexuses with a regular morphology. The spatiotemporal localization of angiogenic factors and the extracellular matrix play fundamental roles in ensuring the proper regulation of angiogenesis. This review article highlights how and what kinds of extracellular environmental molecules regulate angiogenesis. Close interactions between the vascular and neural systems involve shared molecular mechanisms to coordinate developmental and regenerative processes. This review article focuses on current knowledge about the roles of angiogenesis in peripheral nerve regeneration and the latest therapeutic strategies for the treatment of peripheral nerve injury.

Multimodal approach in the diagnosis of changes in the organ of vision at atherosclerosis

Purpose. To study the parameters of OCTA with changes in the organ of vision against the background of atherosclerosis. Results. The registration of OCTA in patients of group I, a decrease in the density of capillaries of the superficial vascular network was 15% and amounted to 45.21±2.62% (p<0.05), of the deep vascular plexus by 19%, which amounted to 45.89±2.71% (p<0.05). Analysis of OCTA in patients of group II revealed a sharp decrease (by 48%) in the density of capillaries in both the superficial and deep vascular plexuses of the retina, which amounted to 33.91±3.01% (p<0.05) and 33.65±2.89% (p<0.05), respectively. Conclusion. The use of OCTA allows to detect changes in hemoperfusion in all layers of the retina and optic nerve in the early stages of atherosclerosis development, which will allow early diagnosis and monitoring of the disease. Key words: organ of vision, atherosclerosis, optical coherence tomography with angiography.

Volume Rendering of Angiographic Optical Coherence Tomography Angiography in Fovea Plana and Normal Foveal Pit

This paper aims to study adaptative vascular arrangements in idiopathic fovea plana with volume-rendered optical coherence tomography angiography (OCTA). A retrospective review of two cases of idiopathic fovea plana (mean age: 26.5 years) and two age-matched controls imaged with OCTA was conducted using spectral-domain OCTA (RTVue XR Avanti, Optovue, Inc., Fremont, CA) equipped with the AngioVue software. Both en face OCTA slabs and OCTA b scans were processed through Fiji software (http://fiji.sc; software version 2.0.0-rc-68/1.52e), and then extracted as image sequences for volume rendering reconstructions using the ImageVis3D volume rendering system (3.1.0 release). Eyes with idiopathic fovea plana demonstrated a regular superficial vascular plexus connecting to a single vascular monolayer representing the deeper vascular plexuses. At this location, several vertical short path connections were demonstrated, in contraposition with normal eyes where short path connections were infrequently observed. Advances in three-dimensional OCTA reconstruction increase the understanding of vascular connections and arrangement in retinal plexuses and possible anatomical variations that cannot be detected with conventional two-dimensional b scans.

The Contribution of Microglia to the Development and Maturation of the Visual System

Microglia, the resident immune cells of the central nervous system (CNS), were once considered quiescent cells that sat in readiness for reacting to disease and injury. Over the last decade, however, it has become clear that microglia play essential roles in maintaining the normal nervous system. The retina is an easily accessible part of the central nervous system and therefore much has been learned about the function of microglia from studies in the retina and visual system. Anatomically, microglia have processes that contact all synapses within the retina, as well as blood vessels in the major vascular plexuses. Microglia contribute to development of the visual system by contributing to neurogenesis, maturation of cone photoreceptors, as well as refining synaptic contacts. They can respond to neural signals and in turn release a range of cytokines and neurotrophic factors that have downstream consequences on neural function. Moreover, in light of their extensive contact with blood vessels, they are also essential for regulation of vascular development and integrity. This review article summarizes what we have learned about the role of microglia in maintaining the normal visual system and how this has helped in understanding their role in the central nervous system more broadly.

Anatomy and Development of the Pectoral Fin Vascular Network in the Zebrafish

The pectoral fins of teleost fish are analogous structures to human forelimbs, and the developmental mechanisms directing their initial growth and patterning are conserved between fish and tetrapods. The forelimb vasculature is critical for limb function, and it appears to play important roles during development by promoting development of other limb structures, but the steps leading to its formation are poorly understood. In this study, we use high-resolution imaging to document the stepwise assembly of the zebrafish pectoral fin vasculature. We show that fin vascular network formation is a stereotyped, choreographed process that begins with the growth of an initial vascular loop around the pectoral fin. This loop connects to the dorsal aorta to initiate pectoral vascular circulation. Pectoral fin vascular development continues with concurrent formation of three elaborate vascular plexuses, one in the distal fin that becomes the fin ray vasculature and two near the base of the fin in association with the developing fin musculature. Our findings detail a complex yet highly choreographed series of steps involved in the development of a complete, functional organ-specific vascular network.

CLINICAL AND PARACLINICAL CRITERIA FOR LIKELYHOOD OF INFECTION AND DEVELOPMENT OF CONGENITAL PNEUMONIA IN NEWBORN CHILDREN WITH CHLAMYDIAL INFECTION

Introduction. Issues of the prevention of intrauterine diseases, and, in particular, congenital pneumonia, in newborns with Chlamydia infection, is still remaining unsolved due to the insufficiently developed criteria for diagnosis of the infection and identification of this pathology progression. The aim of this study is to develop clinical, laboratory and instrumental factors of the Chlamydia infection and the development of congenital pneumonia in newborns. Materials and methods. We examined 77 newborns (38 (49.3%) premature children, 39 (50.7%) full-term children). In the main group 54 newborns were diagnosed to have with congenital pneumonia, on them 25 (46.3%) premature and 29 (53.7%) full-term children. The control group included 23 "conditionally healthy" newborns, of the 13 (56.5%) premature and 10 (43.5%) full-term children. The diagnosis of congenital pneumonia in newborns with Chlamydia infection was confirmed based on the anamnesis, clinical criteria, risk factors over the ante-, intra- and postnatal periods, pathological changes detected on neurosonography, disorders of the intestinal microbiocenosis. Specific diagnosis was performed by the method of polymerase chain reaction with the detection of Chlamydia DNA in the blood serum of newborns. Results and discussion. Comprehensive examination of newborns with congenital pneumonia demonstrated that all newborns in this group were born to mothers infected with Chlamydia, who had burdened obstetric and gynaecological history, complicated pregnancy (due to the presence of a large percentage of extragenital and genital pathology and pathological course of childbirth of pregnant women). It was found that ventricular dilatation, cysts of vascular plexuses and leukomalacia, movement disorders and organic lesions of the central nervous system occurred only in children with congenital pneumonia. It has been demonstrated that the severity of congenital pneumonia in the examined newborns is determined by the contamination of the body with pathogenic flora (Pseudomonas aeruginosa, St. aureus, Klebsiella, Candida). Conclusion. Applying a set of diagnostic criteria for early detection of congenital pneumonia and its progression in children with Chlamydia infection enables to verify the diagnosis and timely prescribe etiotropic therapy in the first days of newborns’ life.

Retinal microcirculation abnormalities in patients with systemic sclerosis: an explorative optical coherence tomography angiography study

Objectives To investigate subclinical and clinical abnormalities in retinal and choroidal vascular plexuses in patients with SSc by means of optical coherence tomography angiography (OCT-A). Methods A total of 20 consecutive SSc patients were recruited and compared with 20 healthy subjects. Quantitative analysis of vessel density (VD), choriocapillaris plexus flow index (CCP-FI) and choroidal vascularity index were performed on OCT-A images in the superficial capillary plexus (SCP), deep capillary plexus (DCP) and CCP for all patients. Images were further reviewed by two independent readers for the assessment of qualitative abnormalities, including tortuosity, rarefaction areas, megacapillaries and macular-foveal capillaries. Results The DCP-VD in the whole scan and in the perifoveal, superior, inferior, nasal and temporal regions was significantly lower in the SSc group. The CCP-FI was significantly higher in SSc patients. When comparing SSc patients with and without digital ulcers, significantly decreased SCP-VD was demonstrated in the whole, perifoveal, superior, inferior, temporal and nasal regions. No difference in any of the OCT-A parameters was observed when comparing patients with and without interstitial lung disease. Qualitative analysis of OCT-A revealed at least one abnormality in 95% of patients. Conclusion We showed the ability of OCT-A to disclose early ocular vascular abnormalities in patients with SSc. Our results may represent a hypothesis-generating basis for exploring the potential role of OCT-A in diagnosis, monitoring and prognosis stratification in SSc.