Single Layer Of Endothelial Cells Research Articles

A novel PDCD10 gene mutation in cerebral cavernous malformations: a case report and review of the literature.

Cerebral cavernous malformations (CCMs) are one of the most common types of vascular malformation, which are featured enlarged and irregular small blood vessels. The cavernous cavities are merely composed of a single layer of endothelial cells and lack other support tissues, such as elastic fibers and smooth muscle, which make them elastic. CCMs may develop in sporadic or familial forms with autosomal dominant inheritance. Mutations have been identified in three genes: KRIT1, MGC4607, and PDCD10. Here, we report a typical case of CCMs in a 44-year-old woman associated with a novel mutation in PDCD10 gene. The patient, diagnosed with CCMs, has been suffering from headache for several months. Analyses of the Whole Exome Sequencing revealed a novel disease-associated mutation in the already known disease-associated PDCD10 gene. This mutation consists a nucleotide deletion (c.212delG) within the exon 4, resulting in premature protein termination (p.S71Tfs*18). This novel mutation significantly enriches the spectrum of mutations responsible for CCMs, providing a new evidence for further clarifying the genotype–phenotype correlations in CCMs patients.

Anti-endothelial cell antibody rich sera from rheumatic heart disease patients induces proinflammatory phenotype and methylation alteration in endothelial cells

Rheumatic heart disease (RHD) is a major cause of cardiovascular morbidity and mortality in developing nations like India. RHD commonly affects the mitral valve which is lined by a single layer of endothelial cells (ECs). The role of ECs in mitral valve damage during RHD is not well elucidated. In here, anti-endothelial cell antibody from RHD patients has been used to stimulate the ECs (HUVECs and HMVECs). ECs proinflammatory phenotype with increased expression of TNFα, IL-6, IL-8, IFNγ, IL-1β, ICAM1, VCAM1, E-selectin, laminin B, and vimentin was documented in both ECs. The promoter hypomethylation of various key inflammatory cytokines (TNFα, IL-6, and IL-8), integrin (ICAM1) associated with leukocyte transendothelial migration, and extracellular matrix genes (vimentin, and laminin) were also observed. Further, the in-vitro data was in accordance with ex-vivo observations which correlated significantly with the etiological factors such as smoking, socioeconomic status, and housing. Thus, the study sheds light on the role of ECs in RHD which is a step forward in the elucidation of disease pathogenesis.

Vascular heterogeneity and specialization in development and disease.

Blood and lymphatic vessels pervade almost all body tissues and have numerous essential roles in physiology and disease. The inner lining of these networks is formed by a single layer of endothelial cells, which is specialized according to the needs of the tissue that it supplies. Whereas the general mechanisms of blood and lymphatic vessel development are being defined with increasing molecular precision, studies of the processes of endothelial specialization remain mostly descriptive. Recent insights from genetic animal models illuminate how endothelial cells interact with each other and with their tissue environment, providing paradigms for vessel type- and organ-specific endothelial differentiation. Delineating these governing principles will be crucial for understanding how tissues develop and maintain, and how their function becomes abnormal in disease.

The impact of hyperglycemia on adhesion between endothelial and cancer cells revealed by single-cell force spectroscopy.

The impact of hyperglycemia on adhesion between lung carcinoma cells (A549) and pulmonary human aorta endothelial cells (PHAEC) was studied using the single-cell force spectroscopy. Cancer cells were immobilized on a tipless Atomic Force Microscopy (AFM) cantilever and a single layer of endothelial cells was prepared on a glass slide. The measured force-distance curves provided information about the detachment force and about the frequency of specific ligand-receptor rupture events. Measurements were performed for different times of short term (up to 2h) and prolonged hyperglycemia (3h - 24h). Single-cell force results were correlated with the expression of cell adhesion molecules (intercellular adhesion molecule, P-selectin) and with the length and density of the PHAECs glycocalyx layer, which were measured by AFM nanoindentation. For short-term hyperglycemia, we observed a statistically significant increase of the adhesion parameters that was accompanied by an increase of the glycocalyx length and expression of P-selectin. Removal of hyaluronic acid from PHAECs glycocalyx significantly decreased the adhesion parameters, which indicates that hyaluronic acid has a strong impact on adhesion in A549/PHAEC system in short term of hyperglycemia. For prolonged hyperglycemia, the most significant increase of adhesion parameters was observed for 24hours and this phenomenon correlated with the expression of adhesion molecules and a decrease of the glycocalyx length. Taking together, presented data indicate that both mechanical and structural properties of the endothelial glycocalyx strongly modulate the adhesion in the A549/PHAEC system.

Aortic arch in rabbits: Morophological and Histological study

The study aimed to investigate the morphological and histological variations of the aortic arch of local breed rabbits (Oryctylagus conniculus). Nine adult local rabbits were obtained to study the aortic arch (four animals for corrosion cast technique, two injected with colored latex and three for histological study). All the rabbits were euthanized and exsanguinatd, for the cast of the aortic arch they injected by self polymerizing resin via the left ventricle of the heart and the specimens were macerated in (KOH %25) for two weeks and the cast of the aortic arch were prepared. Two main branches were identified from aortic arch (except in one cadaver has three branches). The brachiocephalic trunk firstly and the left subclavian artery, the two common carotid artery (right and left) and the right subclavian artery arising from brachiocephalic trunk, the right and left subclavian arteries gave the same branches (double vertebral arteries, costocervical trunk, cervical profound artery, internal thoracic artery, external thoracic artery, superficial cervical artery and continuous as axillary artery). Histologically the wall of the aortic arch is consist of three layers from internal to external: tunica intima, it's the thinnest layer (1±0.166) µm, tunica media, it's the thickest layer (12±0.0149)µm and tunica adventitia, the thickness of this layer is (5±0.166)µm. Tunica intima consisted of single layer of endothelial cells, tunica media consisted of numerous elastic lamina in a circular arrangement and the tunica adventitia was consisted of connective tissue, smooth muscle fibers, collagen fibers, few elastic fibers, fibroblast cells, and mast cells vasavasorum. The aortic arch has a large diameter (98±0.2019)µm and thickness of the wall is (18±0.0282)µm to convey the high blood pressure in aortic arch. In conclusion, there was a variation in the branches of the aortic arch in different species of animals when the results compared with other studies and also, the diameter, thickness of the wall of aortic arch varies from one animal to another.

Intravascular histiocytosis (IVH): A case report

Intravascular histiocytosis is a rare reactive cutaneous lesion of unknown pathogenesis. It is characterised by dilated vessels in the dermis containing aggregates of mononuclear histiocytes within the lumina. Most cases are reported in association with rheumatoid arthritis and cutaneous eruption typically occurs near swollen joints. The skin changes have included erythematous and violaceous macules, papules, plaques and indurated patches. We report a case of 80 years old female presented with a large erythematous patch around the right anterior shoulder joint where surgery was performed about 2 months previously. The erythematous patch was clinically thought to be erysipelas or cellulites and treated with antibiotics without response. We received a punch biopsy of skin measuring 4×6 mm. Microscopic examination of routine H&E stains revealed ectatic thin walled vessels in the dermis, the lumina of which are filled with histiocytes (macrophages). The vessels are lined by flattened single layer of endothelial cells. CD 68 and CD 31 immunostains demonstrate the macrophages within thin walled vessels. Morphological features and immunostains are consistent with intravascular histiocytosis. Diagnosis of IVH is important and may necessitate further clinical evaluation to exclude the possibility of co-existent systemic disease.

A Case of Intravascular Papillary Endothelial Hyperplasia of Eyelid

Purpose: To report a case of intravascular papillary endothelial hyperplasia of the eyelid. Case summary: A 30-year-old male presented with a right upper eyelid mass, which had been growing in size for three years. The mass was about 7 mm in diameter, purplish, spherical, and cystic. Incision and drainage were performed, but the cystic mass instantly refilled with blood. Excisional biopsy was performed. On microscopic examination, a myriad of small delicate papillae projections into the dilated vascular lumen with organizing thrombus were noted. Each papilla was lined with a single layer of endothelial cells, surrounding a collagenized core. The endothelial cells were reactive for CD31 on immunohistochemical staining. There were focal areas of frequent mitoses, but neither cytological atypia nor necrosis was found. Hence, the lesion was diagnosed as intravascular papillary endothelial hyperplasia. Conclusions: Intravascular papillary endothelial hyperplasia in the periorbital area is rarely reported, and it is important to distinguish it from hemangioma or angiosarcoma. Complete surgical excision is necessary to prevent recurrence. The authors report a case of intravascular papillary endothelial hyperplasia of the upper eyelid, which should be considered in the differential diagnosis of eyelid or orbital tumor. J Korean Ophthalmol Soc 2016;57(8):1299-1302

A new tissue-engineered biodegradable surgical patch for high-pressure systems †.

Ideal alternatives for replacing native arteries, which have biocompatibility such as growth potential, anti-thrombogenesis and durability, have yet to be discovered. We previously demonstrated the utility of tissue-engineered vascular autografts; however, the use of these autografts is limited to low-pressure conditions. The aim of this study was to create the tissue-engineered arterial patch (TEAP) that could be used in high-pressure systems, and to evaluate the maturation in this regenerative tissue. We developed a new biodegradable polymer scaffold, which is composed of a co-polymer of epsilon-caprolactone and lactide acid [P(CL/LA)] and a poly-L-lactide acid (PLLA). To obtain mechanical strength, we modified PLLA that is degraded by hydrolysis for 1-2 years in contrast to polyglycolic acid in our low-pressure study previously. We implanted an oval-shaped patch (30 × 15 mm) of this polymer without cell seeding into the descending aorta of 12 dogs, and followed the animals for 1, 3 and 6 months (n = 4 in each group). The cell proliferation in the patch was evaluated with histological and immunohistochemical methods. Additionally, the expression of vascular endothelial growth factor (VEGF) and smooth muscle myosin heavy chain (smMHC) mRNA in the patches was determined with reverse transcriptase-polymerase chain reaction. Macroscopically, there was no incidence of rupture or aneurysmal formation on the patch. The luminal surface of the TEAP was covered with a single layer of endothelial cells stained with vWF immunohistochemically at 1 month after implantation. αSMA-positive cells that indicated smooth muscle cells and collagen fibres were observed in the patch and they increased over time. The VEGF mRNA expression in the patch at 1 month was significantly higher than that of native arterial tissue (1 month; 0.124 ± 0.017 ng/µl, native; 0.009 ± 0.003 ng/µl, P < 0.05). The smMHC mRNA expression gradually increased, and reached ∼ 60% of that of the native artery at 6 months (6 months: 0.351 ± 0.028 ng/µl, native: 0.540 ± 0.027 ng/µl). We demonstrated the maturation of endothelial and smooth muscle cells in TEAP, suggesting that this biodegradable polymer scaffold could be used as an alternative vascular material even in high-pressure systems.

English

The Editor, Sir, Haemangiomas were first described by Payne in 1869 (1). In the literature, their coexistence with various diseases of the female genital tract has been reported (2–5). Our case differs in that a postmenopausal woman had a mucinous cystadenoma in one ovary and an incidentally discovered cavernous haemangioma with focal positivity for progesterone receptor (PR) in the other ovary. An 81-year old woman had right lower quadrant pain. Transabdominal sonography revealed a 10 cm right ovarian cystic and septated mass. No left adnexal lesion was reported. There was no sign of ascites. The serum cancer antigen (CA) 125 level of the patient was 144.9 IU/mL (ref 0–35), serum Ca-19–9 level was 24.9 IU/mL (ref 0–39). Magnetic resonance images revealed a well circumscribed, slightly lobulated contoured, T1 SE hypo-, T2 SE hyperintense, multilocular cystic lesion in the right half of the pelvis (Figs. 1A–D). The left ovary measured 34 × 14 × 35 mm with slight spiculations and was isointense to myometrium on T1 SE and T2 SE weighted sequences (Fig. 1A–B). With injection of contrast material, slightly heterogeneous parenchymal contrast enhancement less than the myometrium was observed (Fig. 1A–D). Fig. 1 Magnetic resonance imaging shows right ovarian lesion to be a multilocular cyst; (A) homogeneous hypo-signal intensity on T1-weighted images and (B) high signal intensity on T2-weighted images. Left ovary has slight spiculations isointense on T1 and T2 ... The result of the right ovary was reported as a mucinous cystadenoma on frozen section (Fig. 2). Fig. 2 Histologically, the right ovarian cyst was lined by mucinous epithelium (HE × 20). On the cut surface of the left ovary (4 × 3 × 1.5 cm in size), a haemorrhagic nodular lesion, 2.5 × 1.5 cm in size, was noted. Microscopic sections revealed dilated, thin-walled vascular structures, variable in diameter, and the walls of which were comprised a single layer of endothelial cells not showing atypia (Fig. 3). Fig. 3 Near the ovarian stroma, dilated thin walled vessels were lined by a single layer of endothelial cells, containing red blood cells in their lumen (HE × 4). Based on macroscopic, morphologic and immunohistochemical findings of factor 8 (FVIII), CD 34, smooth muscle actin (SMA) expression, the case was reported as ovarian cavernous haemangioma. Oestrogen receptor (ER) was negative; however, some endothelial cells were positive for PR (Fig. 4). Fig. 4 Immunohistochemical findings; (A): strong positivity for factor 8 and (B): CD 34 in cells lining the cavernous vessels; (C): immunoreactivity for smooth muscle action in the walls of the vessels; (D): focal positivity for progesterone receptor in the ... Ovarian tumour coexisting with an incidental haemangioma has been previously reported (2–5). A review of the literature reveals that the present case was different in terms of capillary haemangioma in a postmenopausal patient with positive PR receptor (Table). Table Clinicopathologic features of patients with ovarian haemangioma and coexistent lesions reported in the literature The ovarian hilus had a histological appearance that is often confused with haemangiomas due to its rich vascular structure. A mass composed of large vascular channels, nodular formation and minimal amounts of stroma might be helpful to distinguish haemangiomas from dilated, hilar vascular structures (6). In the present case, the mass was composed of dilated blood vessels with little stroma and this helped to establish the diagnosis of haemangioma. The pathogenesis of stromal luteinization remains complicated and it is still controversial whether luteinized stromal cells promote the development of haemangiomas (7). Some authors have studied immunohistochemical expression of ER and PR, and they have found different results (3, 7). In the present case, luteinization was not observed. Moreover, endothelial cells were negative for ER, but some endothelial cells were positive for PR. Radiological appearance for the left ovary was inconclusive; the presence of an enlarged ovary (8) and visualization of contrast uptake on preoperative magnetic resonance imaging in a postmenopausal woman supported rich vascular structure. In postmenopausal women, enlarged ovaries with or without contralateral lesions should be evaluated cautiously.

Vascular hyperpermeability and aging.

Vascular hyperpermeability, the excessive leakage of fluid and proteins from blood vessels to the interstitial space, commonly occurs in traumatic and ischemic injuries. This hyperpermeability causes tissue vasogenic edema, which often leads to multiple organ failure resulting in patient death. Vascular hyperpermeability occurs most readily in small blood vessels as their more delicate physical constitution makes them an easy target for barrier dysfunction. A single layer of endothelial cells, linked to one another by cell adhesion molecules, covers the interior surface of each blood vessel. The cell adhesion molecules play a key role in maintaining barrier functions like the regulation of permeability. Aging is a major risk factor for microvascular dysfunction and hyperpermeability. Apart from age-related remodeling of the vascular wall, endothelial barrier integrity and function declines with the advancement of age. Studies that address the physiological and molecular basis of vascular permeability regulation in aging are currently very limited. There have been many cellular and molecular mechanisms proposed to explain aging-related endothelial dysfunction but their true relationship to barrier dysfunction and hyperpermeability is not clearly known. Among the several mechanisms that promote vascular dysfunction and hyperpermeability, the following are considered major contributors: oxidative stress, inflammation, and the activation of apoptotic signaling pathways. In this review we highlighted (a) the physiological, cellular and molecular changes that occur in the vascular system as a product of aging; (b) the potential mechanisms by which aging leads to barrier dysfunction and vascular hyperpermeability in the peripheral and the blood-brain barrier; (c) the mechanisms by which the age-related increases in oxidative stress, inflammatory markers and apoptotic signaling etc. cause endothelial dysfunction and their relationship to hyperpermeability; and (d) the relationship between aging, vascular permeability and traumatic injuries.

EComment. Is adventitial dissection enough as a simple and effective way to reduce radial artery spasm?

We read with great interest the article by Sandker et al. on the effectiveness of reduced radial artery (RA) spasm in coronary bypass surgery by dissecting the adventitia [1]. The authors conclude that the RA is less susceptible to vasoconstriction and more prone to vasorelaxation ex vivo after adventitial dissection and results in an increase in free blood flow through the RA before anastomosis. The tunica intima includes a single layer of endothelial cells lining the vessel lumen and the internal elastic lamina membrane. The tunica media comprises the muscular portion of the blood vessel, whereas the tunica adventitia includes the external elastic lamina, terminal nerve fibres, and surrounding connective tissue, which contains fibroblasts and tissue macrophages. A preserved adventitia provides structural support to the vessel, which may limit flow-related vascular enlargement and modulation of the vascular tone.

Development and pathologies of the arterial wall.

Arteries consist of an inner single layer of endothelial cells surrounded by layers of smooth muscle and an outer adventitia. The majority of vascular developmental studies focus on the construction of endothelial networks through the process of angiogenesis. Although many devastating vascular diseases involve abnormalities in components of the smooth muscle and adventitia (i.e., the vascular wall), the morphogenesis of these layers has received relatively less attention. Here, we briefly review key elements underlying endothelial layer formation and then focus on vascular wall development, specifically on smooth muscle cell origins and differentiation, patterning of the vascular wall, and the role of extracellular matrix and adventitial progenitor cells. Finally, we discuss select human diseases characterized by marked vascular wall abnormalities. We propose that continuing to apply approaches from developmental biology to the study of vascular disease will stimulate important advancements in elucidating disease mechanism and devising novel therapeutic strategies.

Benign lymphangioendothelioma: a clinical, histopathologic and immunohistochemical analysis of four cases

Benign lymphangioendothelioma represents a rare lymphatic vascular proliferation characterized by proliferation of irregular and thin-walled vessels dissecting amongst dermal collagen. Immunohistochemical analysis has been lacking in most previously reported cases. Herein, we report the clinical and histopathologic characteristics of four cases of benign lymphangioendothelioma. Immunohistochemical study was completed for all lesions. All lesions presented as large, red to brown patches or plaques. Three lesions were located on the thigh and one lesion was located on the neck. Histopathologically, all lesions showed proliferation of anastomotic or retiform thin-walled vessels with a single layer of endothelial cells that dissect the dermis. D2-40 and Prox1 immunostains were positive and Wilms tumor 1 (WT-1) immunostain was negative in all cases. Benign lymphangioendothelioma represents a lymphatic vascular proliferation. A lack of expression of WT-1 suggests it represents a lymphatic vascular malformation.

Solitary angiokeratoma on palms and soles: A clinicopathological analysis of 21 cases

Angiokeratoma includes a group of unrelated diseases characterized by hyperkeratosis and dilation of vessels in the superficial dermis. In this study, 21 cases of solitary lesions located on palms and soles and histopathologically diagnosed as angiokeratoma were analyzed retrospectively. All lesions presented as red to violet macules or plaques. Histopathologically, all of them showed hyperkeratosis and vascular dilation in the papillary to deep dermis. The elongated vessels were of different sizes and shape, lined by a single layer of endothelial cells. In 13 lesions, the endothelial cells protruded into the lumen, forming a hobnail appearance. Immunohistochemical study showed the endothelial cells were positive for CD31 and CD34, negative for D2-40, and focally positive for Wilms tumor 1 (WT-1) in most cases. Our cases represented a rare type of angiokeratoma located on the palms and soles, in which the focal positivity of WT-1 was different from previously reported vascular proliferations.

Primary Intraosseous Hemangioma in the Frontal Bone

Primary Intraosseous Hemangioma in the Frontal Bone

Abstract LB-341: Immunohistochemical features differentiating newly formed from pre-existing vasculatures .

Abstract Objectives of the study: A great number of in vitro and in vivo studies have suggested that a number of pathways and factors can stimulate angiogenesis and lymphangiogenesis, which facilitate tumor progression and metastasis. The morphological and immunohistochemical profile of newly formed vasculatures, however, has not been elucidated, making it difficult, if not impossible, to differentiate them from the pre-existing ones, and to identify their unique molecular profiles for therapeutic interventions. Methodology: Consecutive tissue sections from 100 age- and type-matched colorectal cancer (CRC) patients with and without positive lymph nodes were subjected to double or triple immunohistichemistry with a panel of stem cell and vasculature-related markers, including cytokeratin (CK) 19, CD133, D2-40, CD31, and CD34. Expression of these markers in morphologically distinct large and small vasculatures with and without disseminated tumor cells was compared. Results: Our study revealed that the endothelial cells of all morphologically distinct large and small vasculatures without disseminated tumor cells within their lumen only expressed either lymphatic duct or blood vessel phenotypic markers. Our study also revealed that a subset of lymph node-positive cases harbored some isolated normal epithelial structures with distinct CK-19 immunostaining within an otherwise CK-19-negative background. These epithelial structures were exclusively located within or adjacent to lymphoid follicles and were often surrounded by tube-like structures that express high levels of lymphatic endothelial marker D2-40. These tube-like structures were more frequently seen at the junctions between pre-invasive and invasive CRC with the following features: (1). they consist of a single layer of endothelial cells that express high levels of both lymphatic duct and blood vessel phenotypic markers, (2). their endothelial walls are often incomplete with disseminated cells physically connected with the adjacent stromal cells or tumor cells within the stroma, and (3). disseminated tumor cells within their lumen express high levels of CK-19. Conclusions: Based on these and other findings, we propose that these tube-like structures represent newly formed vasculatures, which are derived by the convergence of aberrant lymphocyte infiltration and tumor stem cells. Because of their close physical proximity, tumor stem cells within the epithelial and stromal components contribute equally and coordinately to the morphogenesis of new vasculatures that constitutes the basis for the unique morphologic and immunohistochemical features of newly formed vasculatures. Citation Format: Bin Jiang, Myron Arlen, Hongyan Yuan, yan-gao man. Immunohistochemical features differentiating newly formed from pre-existing vasculatures . [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr LB-341. doi:10.1158/1538-7445.AM2013-LB-341

Acral hemosideric lymphatic malformation

Cutaneous lymphatic malformations represent a group of heterogeneous diseases caused by developmental defects of lymphatic system. The purpose of this study was to report the clinical, histopathological and immunohistochemical features of a distinctive lymphatic malformation. Twelve patients with similar clinical and histopathological features were included in this study. Immunohistochemical staining of CD31, D2-40, Prox1 and Wilms tumor 1 (WT-1) were performed on all lesions. All cases were either congenital lesions or developed during the first 2 years of life. All presented as red to brown papules or nodules on acral sites. Histopathologically, the lesions consisted of a dermal proliferation of flat or slit-like vessels lined with a single layer of endothelial cells. Hemosiderin or extravascular red blood cells were present in all cases. The constituent vessels expressed CD31, D2-40 and Prox1 and lacked expression of WT-1. On the basis of the clinical, histopathological and immunohistochemical findings, our cases represent a unique type of lymphatic malformation that we believe is distinct from previously reported vascular proliferations. We propose the name of acral hemosideric lymphatic malformation for this entity.

Composition of the Extracellular Matrix of Lymphatic Novel Threadlike Structures: Is It Keratin?

Background. The lumen of novel threadlike structures (NTSs) is enclosed by a single layer of endothelial cells surrounded by extracellular matrix (ECM). We hypothesized that collagen may be a component of the ECM associated with lymphatic NTSs. Methods. Six female New Zealand white rabbits were anesthetized, and the NTS structures within lymphatic vessels were identified by contrast-enhanced stereomicroscopy or alcian blue staining. Isolated NTS specimens were stained with acridine orange, YOYO-1, and 1,1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate (DiI). The structural and molecular composition of the ECM was investigated using transmission electron microscopy (TEM), electrospray ionization-mass spectrometry, and proteomic analysis. Results. The lymph vessel wall was stained red by DiI, and rod-shaped nuclei were stained green by YOYO-1. The area surrounding the NTS was also stained red and contained green rod-shaped nuclei. TEM images showed that the NTS consisted of many ECM fibers and the ECM fibers appeared to be ~100 nm in diameter and had narrowly spaced striated bands. Proteomic analysis of the lymphatic NTS-associated ECM identified 4 proteins: keratin 10, cytokeratin 3, cytokeratin 12, and soluble adenylyl cyclase. Conclusion. The TEM study suggested that the lymphatic NTS-associated ECM did not contain collagen. This was confirmed by proteomic analysis, which showed that keratin was the major component of the ECM.

Pathology Quiz Case 1

A 72-YEAR-OLD WOMAN PRESENTED WITH A mass in the right side of her neck. The mass, which was located in level III, had initially been noticed 4 months earlier and had been slowly enlarging since then. Physical examination revealed that the mass was superficial, freely mobile, and nontender. The patient’s medical history was remarkable for a diagnosis of tuberculosis, which had previously been treated in China. There was no history of neck trauma or surgery. A computed tomographic scan of the neck with contrast demonstrated a heterogeneous vascular mass (1.8 1.7 1.2 cm) just superficial to the sternocleidomastoid muscle in the right side of the neck. The mass appeared to involve or compress the external jugular vein. A fine-needle aspirate yielded grossly bloody fluid that was nondiagnostic. Subsequently, the mass was excised. On low-power magnification, the lesion was found to be completely contained within a vascular lumen, with regions of hemorrhage and thrombosis (Figure 1). The specimen was composed of papillary processes with a single layer of endothelial cells around a collagen core (Figure 2); it also demonstrated significant hemosiderin staining (Figure 3). The endothelial cells were normal in appearance, without mitotic figures or nuclear atypia (Figure 4). What is your diagnosis?

Effect of Fibrin Glue on the Biomechanical Properties of Human Descemet's Membrane

BackgroundCorneal transplantation has rapidly evolved from full-thickness penetrating keratoplasty (PK) to selective tissue corneal transplantation, where only the diseased portions of the patient's corneal tissue are replaced with healthy donor tissue. Descemet's membrane endothelial keratoplasty (DMEK) performed in patients with corneal endothelial dysfunction is one such example where only a single layer of endothelial cells with its basement membrane (10–15 µm in thickness), Descemet's membrane (DM) is replaced. It is challenging to replace this membrane due to its intrinsic property to roll in an aqueous environment. The main objective of this study was to determine the effects of fibrin glue (FG) on the biomechanical properties of DM using atomic force microscopy (AFM) and relates these properties to membrane folding propensity.Methodology/Principal FindingsFibrin glue was sprayed using the EasySpray applicator system, and the biomechanical properties of human DM were determined by AFM. We studied the changes in the “rolling up” tendency of DM by examining the changes in the elasticity and flexural rigidity after the application of FG. Surface topography was assessed using scanning electron microscopy (SEM) and AFM imaging. Treatment with FG not only stabilized and stiffened DM but also led to a significant increase in hysteresis of the glue-treated membrane. In addition, flexural or bending rigidity values also increased in FG-treated membranes.Conclusions/SignificanceOur results suggest that fibrin glue provides rigidity to the DM/endothelial cell complex that may aid in subsequent manipulation by maintaining tissue integrity.