Higher Vascular Density Research Articles

A Processing Pipeline for Quantifying Lenticulostriate Artery Vascular Volume in Subcortical Nuclei.

Lenticulostriate arteries (LSAs) supply blood to the basal ganglia region. Its lesion causes lacunar stroke and resulting neurological syndromes. However, due to its small caliber and large individual variance, the evaluation of LSAs was limited to descriptive and objective measurements. In this study, we aimed to develop a post-processing method to quantify LSAs in subcortical regions and compare their vascular volume to conventional LSA measurements. A processing pipeline was designed to extract subcortical areas in individual spaces while screening out vessels. The vascular volume of LSAs in the subcortical region was calculated from time-of-flight-magnetic resonance angiography (TOF-MRA) at 7 Tesla. The reproducibility was tested to be good for the vascular volume (n = 5, ICCA = 0.84). Comparing the results to conventional measurements, the vascular volume was significantly correlated with the number of branches (r = 0.402, p < 0.001) and the length (r = 0.246, p = 0.032) of LSAs. By applying the method to a group of healthy volunteers (n = 40), we found that most LSAs crossing through the putamen which thereby has the highest vascular density among subcortical nuclei. In general, we proposed a semi-automated processing pipeline for quantifying the vascular volume of LSAs in subcortical regions. The novel method was tested to be robust and provided reasonable results. This method revealed spatial relationships among the perforating arteries and basal ganglia. The vascular volume can be used to evaluated blood supply of subcortical regions, benefiting the radiologic evaluation of neurodegenerative diseases caused by small vascular lesions.

Could increased expression of aquaporin-1 be an etiological cause in childhood noncommunicating hydroceles that do not regress spontaneously?

Aquaporins are membrane water channel proteins that are expressed in the epithelium and endothelium. Their primary function is to control the flow of water in the membranes of the cells. In this study, we investigated whether there is increased expression of aquaporin-1 in the tunica vaginalis of hydrocele patients in childhood that do not regress spontaneously an whether it has an effect on the etiology of hydrocele. Boys who were diagnosed with hydrocele and scheduled for surgery were included and formed the hydrocele group. Boys in the same age range who underwent surgery for inguinal hernia or undescended testicles were included as a control group. Aquaporin-1 expression was evaluated by immunohistochemical examination of capillaries in tissue samples taken from the tunica vaginalis during the operation. Aquaporin-1-positive vessels were counted by selecting 5 unrelated areas with the highest vascular density, and the average number of vessels was calculated for each case. A total of 48 male patients were included in the study. Of these, 27 constituted the hydrocele group (mean age 3.51±2.59 years), and 21 constituted the control group (inguinal hernia, n=17; undescended testicle, n=4) (mean age 3.95±3.80 years). The mean ages of both groups were statistically similar (p=0.32). The mean numbers of aquaporin-1-positive vessels at the capillaries in the tunica vaginalis of the patients were 20.74±7.10 in hydrocele group and 17.23±4.07 in the control group. The expression of aquaporin-1 in the hydrocele group was significantly higher (p=0.037). It was shown that aquaporin-1 expression was higher in adult cases with hydrocele. Also an increase in aquaporin-1 expression was detected in tunica vaginalis of children with hydrocele in our study. It was thought that aquaporin-1 overexpression may play a role in non-communicating hydroceles in children.

The Immune Microenvironment of Chordomas: An Immunohistochemical Analysis.

Simple SummaryChordoma patients may be amenable to immunotherapy; however, the immune microenvironment of chordomas needs further investigation. We performed the immunohistochemical analysis of a chordoma series, showing that these tumors have a unique microenvironment characterized by the absence of PD-L1 tumor cell expression, but feature PD-L1+ immune cells playing a negative prognostic role.Chordomas are rare sarcomas that are usually treated by surgery and/or radiotherapy since these are chemo-resistant tumors, but immunotherapy could be a possible option for chordoma patients. However, few reports investigating the composition of the chordoma immune microenvironment exist. We immunohistochemically studied 81 chordomas regarding their immune microenvironment factors and compared them with clinicopathological data. Macrophages and CD4 cells were the most prominent inflammatory cell populations, followed by CD8 T cells, while CD20 B cells and high endothelial venules (MECA-79+) were less frequently found. PD-L1 (22C3) expression by inflammatory cells was found in 21 (26%) tumors and was associated with a larger tumor size. None of the cases showed the expression of PD-L1 by tumor cells. Survival analysis showed that younger patients had a better overall survival. Considering the immunohistochemical factors studied, higher CD8, the presence of PD-L1+ immune cells, and higher vascular density were adverse prognostic factors, but in multivariate analysis, only PD-L1+ immune cells retained prognostic significance. To conclude, chordoma tumor cells do not express PD-L1, but PD-L1+ immune cells seem to play a negative prognostic role, supporting the need for further studies in this field and the possible beneficial role of immunotherapy in these patients.

Mild Hypoxia Enhances the Expression of HIF and VEGF and Triggers the Response to Injury in Rat Kidneys.

BackgroundHypoxia contributes to a cascade of inflammatory response mechanisms in kidneys that result in the development of renal interstitial fibrosis and subsequent chronic renal failure. Nonetheless, the kidney possesses a self-protection mechanism under a certain degree of hypoxia and this mechanism its adaptation to hypoxia. As the hypoxia-inducible factor (HIF)–vascular endothelial growth factor (VEGF) axis is a key pathway for neovascularization, the activation of this axis is a target for renal hypoxia therapies.MethodsSprague–Dawley rats were exposed to normobaric hypoxia and subdivided into three groups, namely group A (21% O2), group B (10% O2), and group C (7% O2). Renal tissue samples were processed and analyzed to determine pathological morphological changes, the expression of HIF, VEGF, inflammation factor and vascular density.ResultsWe found that as the duration of hypoxia increased, destructive changes in the kidney tissues became more severe in group C (7% O2). In contrast, the increased duration of hypoxia did not exacerbate kidney damage in group B (10% O2). As the hypoxia was prolonged and the degree of hypoxia increased, the expression of HIF-1α increased gradually. As hypoxia time increased, the expression of VEGF increased gradually, but VEGF expression in group B (10% O2) was the highest. Group C (7% O2) had higher levels of IL-6, IL-10, and TNF-alpha. Additionally, the highest vascular density was observed in group B.ConclusionThese findings suggest that activating the HIF–VEGF signaling pathway to regulate angiogenesis after infliction of hypoxic kidney injury may provide clues for the development of novel CKD treatments.

The Organization of the Sinoatrial Node Microvasculature Varies Regionally to Match Local Myocyte Excitability.

The cardiac cycle starts when an action potential is produced by pacemaking cells in the sinoatrial node. This cycle is repeated approximately 100 000 times in humans and 1 million times in mice per day, imposing a monumental metabolic demand on the heart, requiring efficient blood supply via the coronary vasculature to maintain cardiac function. Although the ventricular coronary circulation has been extensively studied, the relationship between vascularization and cellular pacemaking modalities in the sinoatrial node is poorly understood. Here, we tested the hypothesis that the organization of the sinoatrial node microvasculature varies regionally, reflecting local myocyte firing properties. We show that vessel densities are higher in the superior versus inferior sinoatrial node. Accordingly, sinoatrial node myocytes are closer to vessels in the superior versus inferior regions. Superior and inferior sinoatrial node myocytes produce stochastic subthreshold voltage fluctuations and action potentials. However, the intrinsic action potential firing rate of sinoatrial node myocytes is higher in the superior versus inferior node. Our data support a model in which the microvascular densities vary regionally within the sinoatrial node to match the electrical and Ca2+ dynamics of nearby myocytes, effectively determining the dominant pacemaking site within the node. In this model, the high vascular density in the superior sinoatrial node places myocytes with metabolically demanding, high-frequency action potentials near vessels. The lower vascularization and electrical activity of inferior sinoatrial node myocytes could limit these cells to function to support sinoatrial node periodicity with sporadic voltage fluctuations via a stochastic resonance mechanism.

Autophagic Markers in Chordomas: Immunohistochemical Analysis and Comparison with the Immune Microenvironment of Chordoma Tissues.

Simple SummaryIn contrast to normal notochords, autophagic factors are often present in chordomas. Furthermore, PD-L1+ immune cells also express LC3B, suggesting the need for further investigations between autophagy and the immune microenvironment.Chordomas are notably resistant to chemotherapy. One of the cytoprotective mechanisms implicated in chemoresistance is autophagy. There are indirect data that autophagy could be implicated in chordomas, but its presence has not been studied in chordoma tissues. Sixty-one (61) chordomas were immunohistochemically studied for autophagic markers and their expression was compared with the expression in notochords, clinicopathological data, as well as the tumor immune microenvironment. All chordomas strongly and diffusely expressed cytoplasmic p62 (sequestosome 1, SQSTM1/p62), whereas 16 (26.2%) tumors also showed nuclear p62 expression. LC3B (Microtubule-associated protein 1A/1B-light chain 3B) tumor cell expression was found in 44 (72.1%) tumors. Autophagy-related 16‑like 1 (ATG16L1) was also expressed by most tumors. All tumors expressed mannose-6-phosphate/insulin-like growth factor 2 receptor (M6PR/IGF2R). LC3B tumor cell expression was negatively associated with tumor size, while no other parameters, such as age, sex, localization, or survival, were associated with the immunohistochemical factors studied. LC3B immune cell expression showed a significant positive association with programmed death-ligand 1 (PD-L1)+ immune cells and with a higher vascular density. ATG16L1 expression was also positively associated with higher vascular density. Notochords (n = 5) showed different immunostaining with a very weak LC3B and M6PR expression, and no p62 expression. In contrast to normal notochords, autophagic factors such as LC3B and ATG16L1 are often present in chordomas, associated with a strong and diffuse expression of p62, suggesting a blocked autophagic flow. Furthermore, PD-L1+ immune cells also express LC3B, suggesting the need for further investigations between autophagy and the immune microenvironment.

Microfluidic design of tumor vasculature and nanoparticle uptake by cancer cells

The most challenging phase in the clinical translation of drugs is the complex process of screening various drugs and evaluating their therapeutic effects in vitro and in vivo. Microfluidic models have been recognized as an interesting alternative to animal models for drug screening. Enhanced permeation and retention (EPR) effect is one of the most widely used standard for drug delivery in solid tumors with high vascular density and active angiogenesis. The nascent blood vessels in the tumor vicinity have large gaps between the endothelial junctions which allow nanoparticles to pass through them, resulting in selective extravasation and passive accumulation in the tumor regions. In this study, an attempt has been made to mimic some of the physiological characteristics in solid tumors such as endothelial gap junctions, obstructed blood vessels and EPR using a microfluidic platform for drug screening under dynamic culture conditions. The microfluidic chip was fabricated using soft lithography technique. Numerical simulations were performed to analyze the flow patterns inside the chip. Fluorescent gold nanoclusters (Au NCs) were synthesized and their accumulation in the tumor cells cultured inside the microfluidic chip was studied. The experimental results showed an increased uptake of Au NCs in the cells near the endothelial gap junctions in comparison to the cells away from the junctions. The observations in the study correlated with the leaky nature of the tumor vasculature, owing to the enhancement of vascularization and thereby EPR effect. Hence, the fabricated microfluidic device has the potential of minimizing the number of pre-clinical trials using animal models, allowing easier drug screening.

Quantifying Vascular Density in Tissue Engineered Constructs Using Machine Learning.

Given the considerable research efforts in understanding and manipulating the vasculature in tissue health and function, making effective measurements of vascular density is critical for a variety of biomedical applications. However, because the vasculature is a heterogeneous collection of vessel segments, arranged in a complex three-dimensional architecture, which is dynamic in form and function, it is difficult to effectively measure. Here, we developed a semi-automated method that leverages machine learning to identify and quantify vascular metrics in an angiogenesis model imaged with different modalities. This software, BioSegment, is designed to make high throughput vascular density measurements of fluorescent or phase contrast images. Furthermore, the rapidity of assessments makes it an ideal tool for incorporation in tissue manufacturing workflows, where engineered tissue constructs may require frequent monitoring, to ensure that vascular growth benchmarks are met.

Senescence, immune microenvironment, and vascularization in cardiac myxomas

AimsCardiac myxomas are rare tumors of incompletely elucidated pathogenesis. The aim of this study is to explore the possible presence of a senescence phenotype in cardiac myxomas, associated with an inflammatory and vasculogenic tumor microenvironment. Methods and resultsThis is a retrospective study of 29 cardiac myxomas with immunohistochemical detection of various inflammatory, vascular, and senescence markers. We show that all myxomas contain tumor cells in senescence overexpressing p16, and a fraction of senescent endothelial cells. Macrophages are the principal inflammatory cell population, followed by cytotoxic T cells, with fewer plasma cells, mastocytes, and B lymphocytes. These populations are found in different intratumoral localizations. Larger tumor volume is associated with a lower percentage of myxoid matrix, higher cellularity, higher macrophage, and lower number of mast cells as well as higher PD-L1 expression by inflammatory cells. Higher vascular density is associated with higher percentage of B cells, a lower number of macrophages and higher number of mastocytes, and lower PD-L1 expression by inflammatory cells. Tumors with higher vascular density and higher cellularity show higher amounts of p16 senescent endothelial cells. ConclusionsMyxoma tumor cells are in senescence and reside inside a tumor microenvironment with a distinct inflammatory profile rich in macrophages and cytotoxic T cells, and a rich vasculature, probably attributed to a senescence-associated secretory phenotype.

Comparative Study on the Effect of Injectable Platelet Rich Plasma versus its Topical Application in the Treatment of Thermal Burn in Adult Male Albino Rat: Histological and Immunohistochemical Study

Background: Burn is one of the major health problems and several reports have focused on platelet rich plasma role in treatment of soft tissue lesions.Aim:This work aimed to study the histological effect of injectable platelet rich plasma versus its topical application on skin layers (epidermis and dermis) after thermal burn induction in adult male albino rats.Material and Methods: 60 adult male albino rats were divided into three groups; blood donors group, control and experimental group. The latter was subdivided into subgroups I and II. Subgroup II was subdivided into 3 subgroups. Subgroup IIA: animals were exposed to contact thermal burn without treatment. Subgroup IIB: animals were injected subcutaneously with 0.3 ml of autologous PRP. Subgroup IIC: autologous topical PRP was applied. Skin specimens were obtained at days 7, 14 and 28 post burn and involved in histological and immunohistochemical studies. Results: The results of this study revealed that, treatment with PRP resulted in early and enhanced regeneration of skin burn injury. This was evidenced by light microscopic examination and morphometric studies. The PRP treated subgroups were manifested with early re-epithelialization, collagen fibers regeneration and enhanced neovascularization with restoration of normal histological features of skin tissue. Injectable PRP provides slightly better results regarding collagen deposition, fibroblasts infiltration with significant increase in angiogenesis when compared with topical PRP causing high vascular density in wounds.Conclusion: Early interference by PRP injection or topical application enhances wound healing in second degree burn rat model. More future researches are recommended to assess the efficacy of combined injectable and topical PRP in treating burns.

Comparison between the Foveal Avascular Zone and Macular Capillary Network Density in Diabetic Retinopathy and Normal Retina

Background: Diabetic retinopathy (DR) is mostly a vascular disease where the development of macular oedema and proliferative retinopathy are major causes of visual impairment. Enlargement of the foveal avascular zone (FAZ) is associated with visual deterioration in patients with diabetic retinopathy. Objective: To evaluate the foveal avascular zone (FAZ) and perifoveal capillary network density in the superficial retinal layer (SRL) and deep retinal layer (DRL) in patients with varying severities of diabetic retinopathy (DR). Patients and methods: This is a prospective comparative randomized case-control study consisting of 77 eyes divided into two groups, each group underwent imaging using OCT-A device. Group one: 37 healthy control eyes, and group two: 40 eyes with DM of different degrees of diabetic retinopathy. Subjects were imaged between September 2019 and February 2020 at Kasr El-Ainy Teaching Hospital. Results: The FAZ area at the levels of the superficial and deep vascular networks of eyes with DR were found to be larger compared with those of age-matched healthy controls, and as would be expected, control eyes had higher vascular density in both networks compared with the diabetic eyes. Furthermore, eyes with worse DR stage showed larger FAZ area and lower vascular density values. This study also showed that angiographic parameters, namely FAZ area and vessel density (VD) correlated with best corrected visual acuity. Conclusion: Our study revealed that vascular density and FAZ area can be quantified in DR eyes in a rapid, automated, and noninvasive manner with OCTA. Also foveal avascular zone area and vascular density as measures of DMI correlate with visual acuity in patients with DR.

Comparison between the Foveal Avascular Zone and Macular Capillary Network Density in Diabetic Retinopathy and Normal Retina

Background: Diabetic retinopathy (DR) is mostly a vascular disease where the development of macular oedema and proliferative retinopathy are major causes of visual impairment. Enlargement of the foveal avascular zone (FAZ) is associated with visual deterioration in patients with diabetic retinopathy. Objective: To evaluate the foveal avascular zone (FAZ) and perifoveal capillary network density in the superficial retinal layer (SRL) and deep retinal layer (DRL) in patients with varying severities of diabetic retinopathy (DR). Patients and methods: This is a prospective comparative randomized case-control study consisting of 77 eyes divided into two groups, each group underwent imaging using OCT-A device. Group one: 37 healthy control eyes, and group two: 40 eyes with DM of different degrees of diabetic retinopathy. Subjects were imaged between September 2019 and February 2020 at Kasr El-Ainy Teaching Hospital. Results: The FAZ area at the levels of the superficial and deep vascular networks of eyes with DR were found to be larger compared with those of age-matched healthy controls, and as would be expected, control eyes had higher vascular density in both networks compared with the diabetic eyes. Furthermore, eyes with worse DR stage showed larger FAZ area and lower vascular density values. This study also showed that angiographic parameters, namely FAZ area and vessel density (VD) correlated with best corrected visual acuity. Conclusion: Our study revealed that vascular density and FAZ area can be quantified in DR eyes in a rapid, automated, and noninvasive manner with OCTA. Also foveal avascular zone area and vascular density as measures of DMI correlate with visual acuity in patients with DR.

Endothelial dysfunction and cardiovascular risk in lupus nephritis: New roles for old players?

In systemic lupus erythematosus (SLE) patients, most of the clinical manifestation share a vascular component triggered by endothelial dysfunction. Endothelial cells (ECs) activation occurs both on the arterial and venous side, and the high vascular density of kidneys accounts for the detrimental outcomes of SLE through lupus nephritis (LN). Kidney damage, in turn, exerts a negative feedback on the cardiovascular (CV) system aggravating risk factors for CV diseases such as hypertension, stroke and coronary syndrome among others. Despite the intensive investigation on SLE and LN, the role of endothelial dysfunction, as well as the underlying mechanisms, remains to be fully understood, with no specifically targeted pharmacological treatment. It is not known, in fact, if the activation pathway(s) in venous ECs are similar to the one in arterial ECs and doubts persist on the shared manifestation of microcirculation compared to macrocirculation. In this work, we aim to review the recent literature about the role of endothelial activation and dysfunction in the development of CV complications in SLE and LN patients. We, therefore, focus on arteriovenous similarities and differences and on specific pathways of great vessels compared to capillaries. Critically summarising the available data is of pivotal importance for both basic researchers and clinicians in order to develop and test new pharmacological approaches in the treatment of basic components of SLE and LN.

Evaluation of Intra-Tumoral Vascularization in Hepatocellular Carcinomas.

Intratumoral neovascularization has intricate effects on tumor growth, metastasis, and treatment. Over the last 30 years, Microvessel density (MVD) has been the standard method for laboratory and clinical evaluation of angiogenesis. Hepatocellular carcinoma (HCC) is a typical hypervascularized tumor, and the predictive value of MVD for prognosis is still controversial. According to previous viewpoints, this has been attributed to the determination of hotspot, counting methods, vascular endothelial markers, and different definitions of high and low vascular density; however, the heterogeneity of tumor angiogenesis patterns should be factored. The breakthroughs in artificial intelligence and algorithm can improve the objectivity and repeatability of MVD measurement, thus saving a lot of manpower. Presently, anti-angiogenesis therapy is the only effective systematic treatment for liver cancer, and the use of imaging technology-assisted MVD measurement is expected to be a reliable index for evaluating the curative effect. MVD in multinodular hepatocellular carcinoma represents a subject area with huge understudied potential, and exploring it might advance our understanding of tumor heterogeneity.

Microcirculation alterations in severe COVID-19 pneumonia.

PurposeTo assess the presence of sublingual microcirculatory and skin perfusion alterations in COVID-19 pneumonia.Materials and methodsThis is a preliminary report of a prospective observational study performed in four teaching intensive care units. We studied 27 mechanically ventilated patients with acute respiratory distress syndrome secondary to COVID-19. Sublingual microcirculation was assessed by hand-held videomicroscopy. A software-assisted analysis of videos was performed. We also measured capillary refill time.ResultsPatients were hemodynamically stable with normal lactate (1.8 [1.6–2.5] mmol/L) and high D-dimer (1.30 [0.58–2.93] μg/mL). Capillary refill time was prolonged (3.5 [3.0–5.0] s). Compared to previously reported normal values, total and perfused vascular density (21.9 ± 3.9 and 21.0 ± 3.5 mm/mm2) and heterogeneity flow index (0.91 ± 0.24) were high; and the proportion of perfused vessels (0.96 ± 0.03), microvascular flow index (2.79 ± 0.10), and red blood cell velocity (1124 ± 161 μm/s) were reduced. The proportion of perfused vessels was inversely correlated with total vascular density (Pearson r = −0.41, P = 0.03).ConclusionsCOVID-19 patients showed an altered tissue perfusion. Sublingual microcirculation was characterized by decreases in the proportion of perfused vessel and flow velocity along with high vascular densities. This last finding might be related to enhanced angiogenesis or hypoxia-induced capillary recruitment.

Relationship between vascular densities of choriocapillaris and the whole choroid using OCTA.

To study the vascular density (VD) of choriocapillaris and the whole choroid using optical coherence tomography-angiography (OCTA). Cross-sectional study enrolling healthy individuals between 18 and 35years old and with an axial length (AL) lower than 26mm, who were examined with swept-source OCTA Triton DRI (Topcon). Color pictures of both VD were obtained from a fovea-centered 6 × 6mm macular exam, which were divided into 900 squares and codified into numbers. A total of 50 patients (100 eyes) with a mean age of 27.29 ± 3.90years and a mean AL of 23.67 ± 0.74mm were analyzed. The highest choroidal VD was found in juxtapapillary macula, being followed by the most temporal macula and fovea. The lowest was found in superior and inferior perifoveal areas. The highest VD in choriocapillaris was in the fovea. VD in this layer was uniform, with a decrease from temporal toward nasal. Both VD differed and but correlated, especially in the fovea and in inferior-temporal macula. VD of choriocapillaris and the whole choroid are not similar. The former is maximal in the fovea, and the latter is maximal in the juxtapapillary macula. In general lines, choroidal VD is higher than that of choriocapillaris. Both VD are directly correlated.

Exploring Biological Predictive Factors of Progression After Surgery in High-Risk Renal Cell Carcinoma: Results From the French Cohort of the Randomized S-TRAC Trial Patients.

Objective: We aimed to explore biological predictive factors of progression after surgery in nonmetastatic renal cell carcinoma (RCC) using the collected tumors in the French cohort of the randomized S-TRAC trial patients.Patients and Methods: We analyzed the tumors of the French cohort of STRAC that included 44 cases of clear cell RCC (ccRCC) that were collected from six centers. The main objective was to explore biological predictive factors of progression (defined as PFS) to sunitinib. Broad-spectrum analysis including immunohistochemistry, fluorescent in situ hybridization (FISH), comparative genomic hybridization (CGH) array, and transcriptomic analyses were performed on the tumors.Results:Analysis of vascular density showed type 1 vascular stroma corresponding to high vascular density was associated with progression (p < 0.034). Loss of poly bromo-1 expression showed a distinct profile: a highly histopathological aggressive tumor with a marked angiogenic profile (vascular endothelial growth factor overexpression and immature vascular stroma type 2), no PD1 or PDL1 expression, and wild-type (WT) status of the VHL gene. There were 27 chromosome regions gained in patients with progression (on chromosomes 7 and 16, and to a lesser extent 8, 12, 17, 17, 19, 20 corresponding to 605 associated genes) and 10 regions lost in these same patients on chromosomes 8 and 9, and to a lesser extent 2 and 21 corresponding to 25 associated genes.Conclusion:We found that an angiogenic phenotype defined by a high vascular density with a vascular type 2 stroma was a predictive factor of sunitinib resistance. Regardless of adjuvant treatment, chromosomal gains and losses and genomic alterations including PBRM1 loss were associated with worse outcomes.Clinical Trial Registration: ClinicalTrials.gov number, NCT00375674.

Histopathological hallmarks of cutaneous lesions of capillary malformation-arteriovenous malformation syndrome.

Capillary malformation-arteriovenous malformation (CM-AVM) syndrome is a recently described syndrome with distinctive cutaneous lesions. Very little is known about the histopathology of these lesions. The purpose of the study was to evaluate the histopathological characteristics of the pink macules of the CM-AVM syndrome and to investigate if these pink macules could be classified as capillary malformations or arteriovenous malformations based on their histopathological features. We conducted a retrospective multicenter study involving eight hospitals in Spain. Fifteen biopsies from pink macules of the CM-AVM syndrome were analysed and compared with five biopsies of diverse capillary malformations and three stage I arteriovenous malformations. Pink macules' biopsies of the CM-AVM syndrome showed similar features including a high vascular density encompassing capillaries and numerous thick-walled arterioles mainly located in the superficial dermis, a predominance of elongated over round vessels, scarce or absent erythrocytes within the lumina and discrete perivascular inflammation. CMs were characterized by an increased number of capillary-type vessels mostly rounded and located in the upper dermis. AVMs were composed by highly increased numbers of vessels with a branching pattern involving the full thickness of the dermis, without erythrocytes within the lumina. Wilms tumour 1 protein was positive in the endothelial cells both in pink macules of the CM-AVM and in arteriovenous malformations. Pink macules of the CM-AVM syndrome seem to be different from capillary malformations. Our results suggest that histologically and immunohistochemically they are closer to incipient arteriovenous malformations than to capillary malformations. A deepened knowledge about the nature of these skin lesions will contribute to the better understanding of capillary malformation-arteriovenous malformation syndrome, and will open the possibility of new and more specific treatments in the future.

Features of cotton wool spots in diabetic retinopathy: a spectral-domain optical coherence tomography angiography study.

To describe the features of cotton wool spots (CWSs) in diabetic retinopathy (DR) by using spectral-domain optical coherence tomography (SD-OCT) and optical coherence tomography angiography (OCT angiography). We retrospectively studied patients with DR who presented CWSs and had been imaged by SD-OCT angiography. The retinal layer localisation and dimensions of the CWSs were assessed on SD-OCT, while the decorrelation signal generated by the CWSs and the vascular density (VD) of the superficial capillary plexus (SCP) and deep capillary plexus around the CWSs and in the macula were assessed on OCT angiography. A total of 87 eyes of 57 DR patients were included. All CWSs were located in the retinal nerve fibre layer and exhibited a decorrelation signal on OCT angiography. In 68 eyes (78.1%), hyporeflective cavities appearing as cysts in the CWS were noted, especially when were peripheral and large (P < 0.0001). The thickness averaged 211.8 ± 80.02mm and was positively influenced by recent diabetes history, glycaemic dysregulation, posterior pole localisation and a high VD of the SCP around the CWS, while the surface area averaged 0.33 ± 0.24mm2 and was influenced only by a low VD of the SCP around the CWS (P < 0.001). In 72 eyes (82.7%), the non-perfused areas were predominant in the periphery of the CWS. The features of CWSs are influenced by systemic factors, such as history and severity of diabetes, in association with local factors, such as localisation and retinal ischaemia. The peripheral localisation of ischaemia confirms the hypothesis that CWSs are sentinel lesions.

Effect of circulating estrogen level on the outcome of free fat grafting in nude mice

To investigate the effect of circulating estrogen level on the outcome of free fat grafting in nude mice. Eighteen female nude mice aged 6-8 weeks (weighing, 20-25 g) were randomly divided into 3 groups ( n=6). The nude mice in the ovariectomized group were treated with ovariectomy. The nude mice in the high estrogen group and the normal estrogen group only made the same incision to enter the peritoneum without ovariectomy. The nude mice in the high estrogen group were given the estradiol (0.2 mg/g) every 3 days for 30 days. The other two groups were given the same amount of PBS every 3 days. At 30 days after operation, the tail vein blood of nude mice in 3 groups were detected by estradiol ELISA kit, and the free fat (0.3 mL) donated by the females was injected into the sub-scalp of nude mice. After 8 weeks of fat grafting, the samples were taken for gross observation and weighing, and the prepared slices were stained with HE staining, CD31-perilipin fluorescence staining, immunohistochemical staining of uncoupling protein 1 (UCP1), and immunofluorescence staining of estrogen receptor α. The diameter of adipocytes and vascular density of adipose tissue were measured. The mRNA expressions of UCP1 and estrogen receptor α were detected by realtime fluorescence quantitative PCR (qRT-PCR). All nude mice survived during experiment. ELISA test showed that the concentration of estradiol significantly decreased in the ovariectomized group and increased in the high estrogen group compared with the normal estrogen group ( P<0.05). At 8 weeks after fat grafting, the graft volume from large to small was ovariectomized group, normal estrogen group, and high estrogen group. There was significant difference in wet weight between the ovariectomized group and high estrogen group ( P<0.05). Section staining showed that compared with the normal estrogen group, the adipocytes in the ovariectomized group were larger, the expression of peri-lipoprotein was weaker, the vascular density decreased, and the expressions of UCP1 was negative, and the estrogen receptor α positive cells reduced. The above observation results in the high estrogen group were contrary to those in the ovariectomized group. There were significant differences in the diameter of adipocytes, the vascular density of adipose tissue, the number of the estrogen receptor α positive cells between groups ( P<0.05). The results of qRT-PCR showed that the mRNA expressions of UCP1 and estrogen receptor α significantly increased in the high estrogen group and decreased in the ovariectomized group compared with the normal estrogen group, and the differences were significant ( P<0.05). The level of circulating estrogen has a significant effect on the outcome of free fat grafting in nude mice. Low estrogen level leads to hypertrophy of graft adipocytes, while high estrogen level leads to the production of a large amount of beige fat and high vascular density in fat grafts, which may be related to the activation of estrogen receptor α on adipocytes.