Vascular Epithelium Research Articles

Prospective PED-study of intravitreal aflibercept for refractory vascularized pigment epithelium detachment due to age-related macular degeneration: morphologic characteristics of non-responders in optical coherence tomography

PurposeThe aim of this study was to investigate the outcomes of a fixed intravitreal aflibercept regimen in patients with vascular pigment epithelium detachment (vPED) secondary to age-related macular degeneration with refractory subretinal fluid.MethodsA prospective, interventional case series involved 20 eyes of 20 patients with refractory subretinal fluid and vPED treated with at least three injections of intravitreal anti-VEGF prior to study inclusion. After study inclusion, patients were treated with three injections of intravitreal aflibercept 2 mg/0.05 mL monthly followed by injections every 8 weeks. Best-corrected visual acuity (BCVA) and spectral-domain optical coherence tomography (SD-OCT) were evaluated at all visits. Fluorescein angiography and indocyanine green angiography were performed at baseline and quarterly. Primary outcomes were effectivity of a fixed treatment as measured in change in BCVA, PED greatest linear diameter (GLD), and PED height from baseline to month 12. In an additional post hoc analysis, vPED patients were differentiated into two groups: (1) vPED lesions that showed persistence of subretinal fluid throughout 1 year of treatment and (2) vPED lesions that showed complete resolution of subretinal fluid at least at one of the monthly performed OCT volume scans. Reflectivity values were determined in the subretinal pigment epithelium (RPE) compartment in OCT scans at baseline, month 6 and 12.ResultsA total of 18 patients completed the study protocol. The mean age was 74.8 ± 10.6 years, and six patients were female. The median BCVA of all patients was 72.0 ± 8.0 EDTRS letters at baseline and 72.5 ± 9.5 EDTRS letters at 12-month follow-up (p = 0.7420). The median PED height in all patients as measured in the OCT images significantly decreased from 372.0 ± 140.0 μm to 149.0 ± 142.0 μm after 12 months of treatment (p = 0.0020). Persistent subretinal fluid was present at every OCT control in six patients (group 1). Twelve patients showed resolution of subretinal fluid at least at one OCT control (group 2). Reflectivity values in the sub-RPE compartment in OCT scans were 41.48 ± 4.48 (group 1) and 42.62 ± 12.34 (group 2) at baseline (p = 0.854) and 65.88 ± 6.74 and 50.87 ± 14.11 at month 12 (p = 0.038).ConclusionsIntravitreal aflibercept in refractory vPED leads to a significant reduction in PED height and disease activity as well as preservation of BCVA over 1 year. Persistent subretinal fluid was present in PED lesions with high values of reflectivity under the RPE, suggesting both a diffusion barrier and an increasing fibrovascular maturization of the choroidal neovascularization.Trial registrationClinicalTrials.gov Identifier: NCT03370380

Mebendazole inhibits tumor growth and prevents lung metastasis in models of advanced thyroid cancer.

The most common thyroid malignancy is papillary thyroid cancer. While a majority respond to therapy and have a favorable prognosis, some papillary thyroid cancers persist. This subset may dedifferentiate to anaplastic thyroid cancer, an aggressive, highly invasive and rapidly fatal cancer. Thyroid cancer patients at risk for disease progression and metastasis need earlier, safer and more effective therapies. The purpose of this translational study was to determine if mebendazole could be repurposed to effectively treat thyroid cancer, in particular before metastasis. In vitro, mebendazole potently inhibited the growth of a panel of human papillary and anaplastic thyroid cancer cells. In papillary (B-CPAP) and anaplastic (8505c) cell lines, mebendazole increased the percentage of cells in G2/M cell cycle arrest and induced late stage apoptosis by activation of the caspase-3 pathway. In aggressive 8505c cells, mebendazole significantly repressed migratory and invasive potential in a wound healing and transwell invasion assay and inhibited expression of phosphorylated Akt and Stat3 and reduced Gli1. In vivo, mebendazole treatment resulted in significant orthotopic thyroid tumor regression (B-CPAP) and growth arrest (8505c), with treated tumors displaying reduced expression of the proliferation maker KI67 and less vascular epithelium as indicated by CD31+ immunohistochemistry. Most importantly, daily oral mebendazole prevented established thyroid tumors from metastasizing to the lung. Given the low toxicity and published anticancer mechanisms of mebendazole, this novel preclinical study of mebendazole in thyroid cancer has promising therapeutic implications for patients with treatment refractory papillary or anaplastic thyroid cancer.

Preeclampsia as predisposing factor for hypertensive retinopathy: Participation by the RAAS and angiogenic factors

Preeclampsia (PE) is a hypertensive complication of pregnancy. Its cause is still unknown and it could be a risk factor for future ophthalmic problems. Retinal vascular bed alterations have been described as a consequence of PE, suggesting a retinopathy. Factors related to angiogenesis and vascular permeability, such as vascular endothelial growth factor (VEGF) and pigment epithelium derived factor (PEDF) or components of the renin angiotensin aldosterone system (RAAS), prorrenin/renin receptor ((P)RR) and angiotensin II type I receptor (AT1R) have been located in the retina, participating in other retinopathies, but it is unknown if they could participate in PE. Our aim was to elucidate whether VEGF, PEDF, (P)RR and AT1R could be modified during PE and during hypertension induced in rats with a history of PE. We used female Wistar rats and subrrenal aortic coarctation to induce PE, and after delivery, we induced a second hit by Nω-nitro-L-arginine methyl ester (L-NAME) administration. We measured blood pressure, proteinuria and pups development. In both models, eye fundal exploration and immunoblot for VEGF, PEDF, (P)RR and AT1R were performed. We found that the development of hypertension occurred faster in previously PE rats than in normal animals. VEGF, PEDF, (P)RR and AT1R were increased in PE, but in L-NAME-induced hypertension only (P)RR and AT1R were altered. Eye fundal data indicated that PE induced a level I retinopathy, but L-NAME induced a faster and more severe retinopathy in previously PE animals compared to previously normal pregnancy rats. These results indicate that PE predisposes to development of a faster and more severe retinopathy after a second hit. They also suggest that VEGF and PEDF seem to participate only in PE retinopathy, but in both models, RAAS components seem to have a more critical participation.

Clinical Outcomes From Cultivated Allogenic Stem Cells vs. Oral Mucosa Epithelial Transplants in Total Bilateral Stem Cells Deficiency.

Total bilateral limbal stem cell deficiency results from various pathologies, from burns (either chemical or physical) to Sjogren Syndrome, aniridia or ocular cicatricial pemphigoid. After the loss of stem cells, normal corneal epithelium is replaced by a more opaque and vascularized conjunctival epithelium, causing loss of vision. After 1997, cultivation techniques for limbal stem cells became possible. In parallel, cultivation techniques for oral mucosa epithelial cells were also available. The aim of our review was to summarize the clinical outcomes following allogenic cultured limbal stem cell transplant (allogenic CLET), and on the other hand, oral mucosa derived epithelium transplant (cultivated oral mucosa epithelial transplant—COMET or cultivated autologous oral mucosal epithelial cell sheet—CAOMECS), in the case of total bilateral limbal stem cell loss. Thirty studies matching the inclusion criteria were found. The clinical improvement in both methods was reported similar, with percentages higher than 50% of the treated cases. However, the comparison between studies was difficult to achieve due to the lack of a universal and objective grading tool for assessing post-operative results. The definition of clinical improvement was problematic, because success was defined differently, depending on the study. Moreover, some of the studies followed both autologous and allogenic CLET, but described the results together, for both procedures, and therefore it was impossible to analyze them separately. COMET presented some advantages compared to CLET. By using autologous cells, there was no risk of immune activation and no immunosuppression was needed. COMET, however, might be associated with increased risk of persistent epithelial defects and graft failure, compared with allogenic CLET.

Comparative evaluation of expression of VEGF (vascular endothelial growth factors) in periodontal tissues of healthy, chronic and aggressive periodontitis patients: an immunohistochemical study

Periodontitis is a chronic inflammatory disease of the vascularized supporting tissues of the teeth. Angiogenesis (neovascularization) is the budding of new capillaries and is thought to be an essential process in the development of chronic inflammatory diseases. Inflamed tissues (such as gingiva coincident in periodontal disease) have evidence of enhanced expression of inflammatory mediators, many of which can promote angiogenesis. Of the various cytokines and growth factors that are involved in angiogenesis, the most potent agent that acts specifically on vascular epithelium is Vascular Endothelial Growth Factor. Even though angiogenesis is a prominent feature of both inflammation and healing, information about its role in periodontal lesions is limited. Hence the aim of the present study was the immunohistochemical evaluation of the expression of VEGF in the gingival tissues of chronic and aggressive periodontitis patients compared to the healthy controls. The present study was carried out in a total of 45 subjects with age range of 18-55 years, reporting to the Department of Periodontology, Rajarajeswari Dental College and Hospital, Bangalore. Gingival tissue samples were collected from all the 45 subjects and categorized into three groups based on their clinical findings as follows: Group 1 (Healthy), Group II (Chronic Periodontitis), Group III (Aggressive Periodontitis). Following sample collection, immunohistochemical staining of tissues was carried out and evaluation was done to compare the grades of expression of VEGF in the three groups. The expression of VEGF in blood vessels was also quantitatively evaluated. The results were statistically analyzed using Kruskal Wallis ANOVA and Mann Whitney test. There was a statistically significant higher expression of VEGF in both chronic periodontitis and aggressive periodontitis group as compared to the control group. Aggressive periodontitis cases showed higher grades of expression of VEGF compared to the chronic periodontitis cases and healthy controls. However, the difference in expression of VEGF was not statistically significant between the two forms of periodontitis. The presence of VEGF in both chronic and aggressive periodontitis clearly indicates the potent role played by VEGF as an inflammatory agent in the initiation and progression of periodontal diseases. Thus, VEGF might be used as a potential vascular marker for the assessment of severity and inflammatory status in periodontal disease.

Expression of myofibroblast in gingival after orthodontic loading

To examine the expression of myofibroblast in gingival after orthodontic loading. Eight patients were selected as experimental group and treated with orthodontic force for 4 months. Ten patients were selected as the control group, were not loaded. The gingival protein expressions of collagen typeⅠ, collagen type Ⅲ, α-smooth muscle actin (α-SMA) were evaluated by immunohistochemistry method. Positive expressions of collagen typeⅠ, collagen type Ⅲ were founded, while no positive staining for α-SMA in the gingival tissue except vascular epithelium before loading. In experimental group, collagen type I and collagen type Ⅲ were increased after orthodontic loading (P<0.05), the expression of α-SMA was detected and statistically significant (P<0.05). The myofibroblast exists in gingival tissue after orthodontic loading, and it may be concerned with orthodontic teeth relapse.

Transplantation of autologous perichondrium with amniotic membrane for progressive scleral necrosis

PurposeScleral necrosis with severe ischemia is refractory to conventional treatment because of avascular progressive necrosis. We assessed the therapeutic efficacy and safety of autologous perichondrium transplantation in patients with progressive scleral necrosis (PSN) and analyzed the clinical effects. MethodsThis study was a prospective, interventional, and noncomparative case series. Reconstructive surgery using autologous perichondrium and amniotic membrane (AM) was performed in patients with PSN who showed progressive ischemic scleral melting with impending perforation state and/or broad avascular area larger than 10 mm in diameter. The primary outcome was restoration of scleral integrity with healthy vascularized epithelium over the graft at six months after surgery. The secondary outcome was complication rate associated with autologous perichondrium graft use. ResultsEighteen eyes of 14 patients underwent reconstructive surgery using autologous perichondrium patch and AM grafts. Observations indicated the graft provided the eyeball with successful structural integrity in 17 out of the 18 cases (94.4%) at six months after surgery. One eye showed a small scleral defect due to wound dehiscence at four month after the surgery. Additional surgery using perichondrium and AM stabilized the eye. The scleral necrosis healed completely after perichondrium and AM transplantation, even in cases with full-thickness scleral defect. The scleral integrity was maintained until the last follow-up session. There were no serious complications of endophthalmitis or graft infection. ConclusionsReconstructive surgery using autologous perichondrium and AM is an effective method for restoration of scleral integrity and vascularization of the episclera and conjunctiva in eyes with PSN. Therefore, autologous perichondrium can be considered as an appropriate new biologic tissue for PSN.

Building a Sound Wall in the Cochlea: Development of the Stria Vascularis

The stria vascularis is a specialized epithelial structure of the mammalian cochlea that produces endolymph, the potassium‐rich fluid responsible for the positive endocochlear potential of the cochlear lumen. This positive extracellular potential is the major driving force for proper signal transduction by sensory cells in the ear, and thus normal hearing. The stria vascularis is the “battery” of the auditory organ: it is localized in the lateral wall of the cochlea, and consists of a multilayered highly vascularized epithelium. It is composed of three main cell types with distinct embryonic origins: the marginal cells derived from the otic epithelium , the intermediate cells which are specialized melanocyte‐like cells derived from migratory neural crest cells, and the basal cells that are derived from otic mesenchyme. Mesoderm‐derived blood vessels are interspersed between these cells throughout the stria. Defects in the development of the stria vascularis are part of a number of inheritable deafness syndromes in humans, including Hirschsprung disease and Waardenburg, Jervell and Lange‐Nielsen, Bartter and SeSAME syndromes. Strial degeneration is estimated to cause more than 30% of age related hearing loss or presbycusis, which affects between 25–40% of the population over 65 years and over 60% of the population over 80 years old. The causes of strial atrophy remain poorly understood. Over the past decade, a great effort has been made to understand the development of the sensory cells in the mammalian cochlea with the aim of applying their developmental principles to regenerative therapies. By contrast, very little is known about the developmental potential of the stria vascularis, or even the mechanisms of strial degeneration due to aging. Our focus is to uncover the normal development of the stria, the cellular interactions that lead to its formation, and the potential for regeneration in cases of congenital strial deafness.Support or Funding InformationHearing Health FoundationThe Hartwell FoundationNIDCD R01DC015785This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Estimation of Volume of Stria Vascularis and the Length of Its Capillaries in the Human Cochlea.

Background:The stria vascularis (SV) is a vascularized epithelium that secretes endolymph and is located on the lateral wall of the membranous cochlea. The capillaries of SV directly influence the composition of the endolymph and hence the generation of impulses by the hair-cells that are auditory receptors and thus affect hearing. Therefore, the real morphology of the SV would be very important for understanding the hearing system. There are few reliable reports of the morphology of the human SV.Aims and Objectives:In this research, we have estimated the volume of the SV and total length of strial capillaries in the apical, middle and basal turns of the human cochlea by updated stereological techniques.Methods:The point-counting Cavalieri's method and hemispherical volume probes were applied on stained, 40 μm-thick serial sections of five celloidin-embedded, decalcified cochleae.Results:The mean age of persons at the time of death was 51 ± 15.25 years, the mean volume of the SV was 0.56 ± 0.054 mm3 and the mean length of the SV capillaries was 289.08 ± 72.96 mm. We also estimated the same parameters with different stereological parameters, probes and in differently stained sections and checked the relationship and limits of agreement between different methods by paired t-test and Bland-Altman plot. We found agreement in our results.Conclusion:We provide reliable baseline data on the real morphology of the human SV.

Linking the low-density lipoprotein receptor-binding segment enables the therapeutic 5-YHEDA peptide to cross the blood-brain barrier and scavenge excess iron and radicals in the brain of senescent mice

IntroductionIron accumulates in the brain during aging, which catalyzes radical formation, causing neuronal impairment, and is thus considered a pathogenic factor in Alzheimer's disease (AD). To scavenge excess iron-catalyzed radicals and thereby protect the brain and decrease the incidence of AD, we synthesized a soluble pro-iron 5-YHEDA peptide. However, the blood-brain barrier (BBB) blocks large drug molecules from entering the brain and thus strongly reduces their therapeutic effects. However, alternative receptor- or transporter-mediated approaches are possible. MethodsA low-density lipoprotein receptor (LDLR)-binding segment of Apolipoprotein B-100 was linked to the 5-YHEDA peptide (bs-5-YHEDA) and intracardially injected into senescent (SN) mice that displayed symptoms of cognitive impairment similar to those of people with AD. ResultsWe successfully delivered 5-YHEDA across the BBB into the brains of the SN mice via vascular epithelium LDLR-mediated endocytosis. The data showed that excess brain iron and radical-induced neuronal necrosis were reduced after the bs-5-YHEDA treatment, together with cognitive amelioration in the SN mouse, and that the senescence-associated ferritin and transferrin increase, anemia and inflammation reversed without kidney or liver injury. Discussionbs-5-YHEDA may be a mild and safe iron remover that can cross the BBB and enter the brain to relieve excessive iron- and radical-induced cognitive disorders.

Expression of Three Adipokines (Adiponectin, Leptin and Resistin) in Normal Canine Skin: a Pilot Study

Adipokines are biologically active cytokines that are mainly produced in adipose tissue. There is evidence, in man and mice, that some adipokines may be secreted in other tissues including the vascular endothelium, epithelia and sebaceous glands. Moreover, modified serum levels of adipokines have been detected in people with acne vulgaris or psoriasis; it is suspected that adipokines could contribute to local and systemic inflammatory conditions. We aimed to evaluate the expression of three adipokines (i.e. leptin, adiponectin and resistin) in normal canine skin. Formalin-fixed, paraffin wax-embedded punch biopsy samples were obtained from the sparsely-haired skin of the caudal ventral abdomen of a single clinically healthy dog with no history of skin disease. Immunohistochemistry was applied, using rabbit polyclonal primary antibodies specific for leptin, adiponectin and resistin. Adipokines were not expressed in normal canine dermis or hypodermis. In contrast, they were detected in the keratinocytes of all epidermal layers and hair follicle segments, sebocytes, apocrine gland cells and in the vascular endothelium. This is the first report on the expression of adipokines in normal canine skin, a first step in studying their role in the skin physiology and inflammatory skin diseases of dogs.

Tirofiban, a Glycoprotein IIb/IIIa Antagonist, Has a Protective Effect on Decompression Sickness in Rats: Is the Crosstalk Between Platelet and Leukocytes Essential?

In its severest forms, decompression sickness (DCS) may extend systemically and/or induce severe neurological deficits, including paralysis or even death. It seems that the sterile and ischemic inflammatory phenomena are consecutive to the reaction of the bubbles with the organism and that the blood platelet activation plays a determinant role in the development of DCS. According to the hypotheses commonly put forward, the bubbles could either activate the platelets by direct contact or be the cause of abrasion of the vascular epithelium, which would expose the basal plate glycogen and then prompt the platelets to activate. The purpose of this study is to confirm anti-platelet drugs specific to GPIIb/IIIa integrin could prevent DCS, using a rat model. There is a significant difference concerning the incidence of the drug on the clinical status of the rats (p = 0.016), with a better clinical outcome for rats treated with tirofiban (TIR) compared with the control rats (p = 0.027), even if the three anti-GPIIb/IIIa agents used have limited respiratory distress. TIR limited the decrease in platelet counts following the hyperbaric exposure. TIR help to prevent from DCS. TIR is specific to GPIIb/IIIa whereas eptifibatide and abciximab could inhibit αVβ3 and αMβ2 involved in communication with the immune system. While inhibiting GPIIb/IIIa could highlight a platelet-dependent inflammatory pathway that improves DCS outcomes, we wonder whether inhibiting the αVβ3 and αMβ2 communications is not a wrong approach for limiting mortality in DCS.

N-Acetylcysteine Suppresses LPS-Induced Pathological Angiogenesis

Background/Aims: Angiogenesis is a key feature during embryo development but is also part of the pathogenesis of cancer in adult life. Angiogenesis might be modulated by inflammation. Methods: We established an angiogenesis model in chick chorioallantoic membrane (CAM) induced by the exposure of lipopolysaccharide (LPS), and analyzed the effects of the antioxidant N-acetylcysteine (NAC) on angiogenesis in this model as well as on the expression of key genes known to involved in the regulation of angiogenesis. Results: Treatment with NAC was able to normalize LPS induced angiogenesis and restore the LPS-induced damage of vascular epithelium in chick CAM. Using quantitative PCR, we showed that NAC administration normalized the LPS induced expression of Keap1-Nrf2 signaling and oxidative stress key enzyme gene expressions (SOD, GPx and YAP1). Conclusion: We established a LPS-induced angiogenesis model in chick CAM. NAC administration could effectively inhibit LPS-induced angiogenesis and restore the integrity of endothelium on chick CAM. LPS exposure caused an increased expression of genes involved in oxidative stress in chick CAM. NAC administration could abolish this effect.

Anatomopathologic Study of Kidneys parasitized by Dioctophyme renale in Dogs

Background: Dioctophymiasis is a disease caused by the nematode Dioctophyme renale and is a relatively common condition in dogs. The parasite affects the kidney, especially the right, enters the kidney capsule and causes destruction and atrophy of the parenchyma. The lesion severity depends on the amount of parasites affecting the kidney, the duration of the infection, number of kidneys involved and concurrent occurrence of kidney disease. The disease’s clinical presentation may be asymptomatic or with nonspecific clinical signs. The diagnosis is based on ultrasound examination and the detection of eggs in urine, however, diagnosis is often reached only through necropsy or histopathology. This study aimed to analyze the dog kidney anatomical and pathological changes when parasitized by Dioctophyme renale.Materials, Methods &amp; Results: The kidneys of 21 dogs diagnosed with dioctophymiasis were nephrectomized, analyzed by ultrasound and forwarded to macro and microscopic analysis. Macroscopically, the kidney size was measured as well as its renal capsule thicknes. The presences of dilatation of the renal pelvis and ureter, as well as changes of the capsule, were also observed. These fragments were collected and submitted for routine analysis and stained with hematoxylin and eosin. Histopathological examination was performed blindly by three evaluators. The intensity of fibrosis was evaluated by the presence or absence of infiltration, the absence or presence of parasite eggs and when present whether there was inflammatory tissue response, among other changes. All received organs were right kidneys and showed clear atrophy or absence of the parenchyma. The kidney size ranged from 3,8x2,5x1,3 cm to 8,4x8,2x4,0 cm and the capsule thickness between 0.1 and 3.6cm. In renal capsule were observed whitish, irregular and firm plates (10 out of 21 cases) and papilliform projections (4 out of 21). In two specimens were identified cases of hydroureter and hydronephrosis. Microscopically, all specimens had some degree of fibrosis which replaced the renal parenchyma, six classified as mild, ten were moderate and five intense. In 13 cases there was intense deposition of parasite eggs and 18 cases showed inflammatory infiltrate of which one was pyogranulomatous and one granulomatous. Papilliform projections were observed in six out of 21 cases (composed of connective tissue proliferation and neovascularization), there was also hyperplasia of the pelvis transition epithelial (6 out of 21) and osseous metaplasia of the renal capsule (4 out of 21). The vessels walls were hypertrophic in nine out of 21 cases.Discussion: The diagnosis of dioctophymiasis was performed by ultrasonography. All 21 kidneys analyzed were rights; this is related to the parasite penetration in the duodenal wall, which tends to migrate by anatomic proximity to the right kidneys. Dioctophyme renale feeds through digestion and ingestion of the renal parenchyma by the action of parasite’s oesophageal enzymes causing progressive destruction of the cortical and medullar layers and consequently the proliferation of fibrous tissue. In this study, different intensities of fibrosis were observed. Bone metaplasia characterizes the chronicity of the process and the connective tissue’s attempt to adapt. Animals affected by dioctophymiasis often develop chronic renal failure. Chronic renal failure is characterized by continuous and irreversible morphologic changes in the renal parenchyma with loss of nephron components and the formation of a vicious cycle of replacement by fibrous connective tissue. The hypertrophy of vascular epithelium observed in six cases of this study may be associated with fibrous connective tissue proliferation stimulus. The injuries described here may be related to the parasitosis late diagnosis.

Diagnostic value of microvessel structure in brain glial tumors

Diffuse gliomas are the most common primary brain tumors with a disproportionately high mortality rate. Characteristics of microvessels are of high diagnostic and prognostic significance, however, the results of previous studies are controversial. The aim of the work is to evaluate the features of angiogenesis in diffuse gliomas on the basis of determining the qualitative and quantitative microvascular characteristics. Also important is their relationship with the histological type of tumor. Microvascular density (μm-1), total vascular area (%), total lumen area (%) and the mean diameter of microvessels (μm) were measured and calculated in diffuse brain gliomas (n=76) using GFAP-negative status of endothelium in the presence of exclusively GFAP-positive tumor cells. Proliferation of microvessels was evaluated using proliferation index of vascular epithelium (Ki-67). The possibility of routine evaluation of the angiogenesis in diffuse gliomas using GFAP and Ki-67 markers was defined. We revealed significant correlation between features of the neoplastic microvasculature and WHO Grade.

OCT Angiography of RPE Tears in Exudative AMD: Morpohological Analysis of the Choriocapillaris and the RPE

Background Retinal pigment epithelium (RPE) tears are a typical complication of vascular pigment epithelium detachment in age-related macular degeneration (AMD). During proactive intense anti-VEGF therapy, stabilisation or improvement of function may occur. With the new method of OCT angiography (OCT-A), retinal vessels and flow density can be quantified. This pilot study investigates changes in the choriocapillars (CC) in areas with increasing FAF in OCT following an RPE-tear. Methods In six eyes with an RPE-tear, prospectively initially and every three months thereafter, multimodal imaging was performed, including fundus autofluorescence (FAF) (HRA2, Heidelberg Engineering, Heidelberg, Deutschland) and OCT-A (RTVue XR Avanti, SSDA-Modus, Angiovue, Optovue, Freemont, CA, USA). With interactive MATLAB-software (MATLAB, MathWorks, Natick, MA, USA), FAF and OCT were geometrically superimposed. With the help of the Fiji software (National Institutes of Health, Bethesda, MD, USA), areas with increasing FAF flow intensity in OCT-A with CC-segmentation were measured during an average follow-up period of 12 months. Results We measured a reduction in the RPE-free area - due to an increase in autofluorescence tissue - of an average of 2.94 mm2 (SD 2.1 mm2; 42.1% of initial RPE-free area) in the boundary area of RPE-tears. At the end of the different follow-ups, some patients exhibited lower flow density in areas of regenerated autofluorescence than the initial findings. On the other hand, in some follow-ups, the same or increased flow density was seen. Conclusion In this pilot study, OCT-A was tested to analyse the structure of CC in areas of regenerated FAF after RPE-tears. Using external image editing software, FAF and OCT-A were compared during the follow-up. Thus apparent initial regression of the CC in the area mentioned above could be observed. During the follow-up and development of autofluorescent SHT, CC also regenerates up to the level of the initial findings of CC.

Identification and distribution of neuronal nitric oxide synthase and neurochemical markers in the neuroepithelial cells of the gill and the skin in the giant mudskipper, Periophthalmodon schlosseri

Mudskippers are amphibious fishes living in mudflats and mangroves. These fishes hold air in their large buccopharyngeal-opercular cavities where respiratory gas exchange takes place via the gills and higher vascularized epithelium lining the cavities and also the skin epidermis. Although aerial ventilation response to changes in ambient gas concentration has been studied in mudskippers, the localization and distribution of respiratory chemoreceptors, their neurochemical coding and function as well as physiological evidence for the gill or skin as site for O2 and CO2 sensing are currently not known. In the present study we assessed the distribution of serotonin, acetylcholine, catecholamines and nitric oxide in the neuroepithelial cells (NECs) of the mudskipper gill and skin epithelium using immunohistochemistry and confocal microscopy. Colocalization studies showed that 5-HT is coexpressed with nNOS, Na+/K+-ATPase, TH and VAChT; nNOS is coexpressed with Na+/K+-ATPase and TH in the skin. In the gill 5-HT is coexpressed with nNOS and VAhHT and nNOS is coexpressed with Na+/K+-ATPase and TH. Acetylcholine is also expressed in chain and proximal neurons projecting to the efferent filament artery and branchial smooth muscle. The serotonergic cells c labeled with VAChT, nNOS and TH, thus indicating the presence of NEC populations and the possibility that these neurotransmitters (other than serotonin) may act as primary transmitters in the hypoxic reflex in fish gills. Immunolabeling with TH antibodies revealed that NECs in the gill and the skin are innervated by catecholaminergic nerves, thus suggesting that these cells are involved in a central control of branchial functions through their relationships with the sympathetic branchial nervous system. The Na+/K+-ATPase in mitochondria-rich cells (MRCs), which are most concentrated in the gill lamellar epithelium, is colabeled with nNOS and associated with TH nerve terminals. TH-immunopositive fine varicosities were also associated with the numerous capillaries in the skin surface and the layers of the swollen cells. Based on the often hypercapnic and hypoxic habitat of the mudskippers, these fishes may represent an attractive model for pursuing studies on O2 and CO2 sensing due to the air-breathing that increases the importance of acid/base regulation and the O2-related drive including the function of gasotransmitters such as nitric oxide that has an inhibitory (regulatory) function in ionoregulation.

Fluorescein, indocyanine green and optical coherence tomography angiography in patients with native exudative age-related macular degeneration

The newly developed optical coherence tomography angiography (OCT-A) has provided new means to depict the vascular plexus in neovascular age-related macular degeneration (nAMD). If these images are to be used as abasis for therapeutic decisions, it is of vital importance to classify choroidal neovascularization (CNV) as either classical or occult. This study aimed at comparing the findings in OCT-A imaging of CNV with the traditional multimodal imaging through fluorescein angiography (FLA) and indocyanine green angiography (ICGA). For this investigation 13eyes from 13patients with CNV on the basis of untreated nAMD were studied using FLA, ICGA, spectral domain OCT and OCT-A. All CNV were classified on the basis of SD-OCT and OCT-A images by two independent raters. Thereafter FLA and ICGA images were analyzed to set the gold standard for the classification and the ratings were compared to the previous SD-OCT and OCT-A results. 88% of eyes were correctly classified as either classical or occult CNV on the basis of SD-OCT and OCT-A images. Based on the CNV subgroups, 93% of classical CNV were identified using OCT-A images. In contrast occult CNV was correctly classified in 83% of patients. The interrater agreement was 77%. In general it was noted that the more the retina was pathologically altered, e. g. by edema or vascular pigment epithelium detachment, the harder it became to correctly classify the CNV. These results show that OCT-A can be used as an interesting addition in the diagnosis of CNV in nAMD. All CNV could be visualized using OCT-A and especially classical CNV could be clearly recognized in most cases. In contrast occult CNV could be identified in slightly fewer cases.

Progress in understanding of adrenal insufficiency in septic patients

Background Sepsis is one of the critical complications following serious injuries or major surgeries. It is a leading cause of death. The mortality of septic shock exceeds 40%. Accumulating studies have demonstrated that the severity of adrenal cortex dysfunction has a vital impact on the phenotype and prognosis of sepsis, while glucocorticoid(GC) may be an effective intervention. However, the mechanisms underlying adrenocortical dysfunction remain unclear. Objective To review strategies for assessment of adrenocortical function, and timely supplement of GC, aiming to appropriately compensate the impaired adrenal function, finally, to improve prognosis and to reduce mortality of sepsis. Content At the early stage of sepsis, hypothalamus-pituitary-adrenal axis(H-P-A) is activated, and is followed by release of GC and mobilization of inflammation cascades, especially mitogen-activated protein kinase(MAPK) and nuclear regulatory factor-κB pathways. GC counteracts the inflammation cascades. At the late stage of sepsis or during sepsis shock, damages of adrenocortical cells and vascular epithelia cells occur in adrenal gland, resulting in adrenocortical dysfunction, including low levels of GC and low affinity of GC receptors. The measurement of serum GC and adrenocorticotrophic hormone are combined to assess adrenocortical function: adrenal insufficiency(AI) or relative adrenal insufficiency(RAI). Low doses of GC help to reverse septic shock, improve adrenal function, and maintain normal hemodynamics in septic patients. Trend Further investigation in understanding the mechanisms underlying AI and RAI are highly demanded to optimize therapeutic application of GC in sepsis. Key words: Sepsis; Septic shock; Adrenal insufficiency; Relative adrenal insufficiency

The Epigenetic Machinery in Vascular Dysfunction and Hypertension.

Hypertension (HT) is among the major components of the metabolic syndrome, i.e., obesity, dyslipidemia, and hyperglycemia/insulin resistance. It represents a significant health problem with foremost risks for chronic cardiovascular disease and a significant cause of morbidity and mortality worldwide. Therefore, it is not surprising that this disorder constitutes a serious public health concern. Although multiple studies have stressed the multifactorial nature of HT, the pathogenesis remains largely unknown. However, if we want to reduce the global prevalence of HT, restrain the number of deaths (currently 9.4 million/year in the world), and alleviate the socio-economic burden, a deeper insight into the mechanisms is urgently needed in order to define new meaningful therapeutic targets. Recently, the role of epigenetics in the development of various complex diseases has attracted much attention. In the present review, we provide a critical update on the available literature and ongoing research regarding the epigenetic modifications of genes involved in several pathways of elevated blood pressure, especially those linked to the vascular epithelium. This review also focuses on the role of microRNA (miRNA) in the regulation of gene expression associated with HT and of fetal programming mediating susceptibility to HT in adulthood.