Elastic Tissue Stain Research Articles

Cross-sectional study to evaluate the utility of elastic tissue staining in primary cicatricial alopecia

Background and aimsDiagnosing end-stage primary cicatricial alopecia (PCA) on routine histology is challenging since the major diagnostic feature (inflammatory infiltrate) may be minimal or absent. This study aimed to assess...

Comparison of elastic tissue stain with haematoxylin and eosin stain in the detection of venous invasion in colorectal carcinoma in the Sri Lankan setting

Comparison of elastic tissue stain with haematoxylin and eosin stain in the detection of venous invasion in colorectal carcinoma in the Sri Lankan setting

Scarring versus Non-Scarring Alopecia: An Interobserver Histopathological Reproducibility Study

Introduction: Distinguishing scarring (SA) versus non-scarring alopecia (NSA) may not be a simple procedure on either clinical or histopathological views. Aims: We sought to study the interobserver variability in the histopathological assessment of SA versus NSA, including clinical-pathological considerations. Methods: Two dermatopathologists independently interpreted the same set of 100 specimens (89 patients). The samples were serial sectioned and stained by hematoxylin and eosin and Verhöeff methods. The patients’ mean age was 46 years, with 13 being males and 76 females. Results: In 16/100 samples, there was no consensus among the two examiners regarding SA versus NSA (weighted kappa = 0.6583; 95% CI); 3/16 patients were re-biopsied, and in the second sample, consensus was reached. In 76/89 patients, the anatomopathological examination was helpful in defining the SA versus NSA subtype. Of the 84 samples in which there was interobserver agreement, 4 which had been considered scarring in the routine pathological report were re-classified as non-scarring, whereas one biopsy, previously diagnosed as non-scarring, was now considered cicatricial due to the newly found areas of lichenoid inflammation in the infundibular epithelium. Discussion: The ideal scalp examination may require deep serial biopsy sectioning, elastic tissue stain, re-biopsy, and strict clinical-evolutive correlation.

Kolorektal Kanserlerde Venöz İnvazyonun Elastik Lif Boyası Eşliğinde Yeniden Değerlendirilmesi

Objective: The prognostic importance of venous invasion(VI) in colorectal cancer(CRC) has been known for many years. VI was considered an independent predictor for distant organ metastases. In cases with VI, visceral organ metastases of the tumor occur more rapidly than lymphatic spread. A VI rate of at least 25% was expected in CRC. It was claimed that the use of Elastic Tissue Stain(ETS) increases the VI ratios. In this study, our aim is to reevaluate CRC cases without VI by applying ETS, and to question the routine use of ETS.
 Materials and Methods: Between 2018- 2020, 166 colorectal resection materials diagnosed with cancer were found. VI negative ones were selected. When determining VI, 77 cases were identified that did not have histochemistry/immunohistochemistry. Tissues of 77 cases were reevaluated after ETS was applied.
 Results: 49 of the cases were male(63.6%), 28 of them were female(36.4%). The mean age was 63.5 (29-101) years. The mean tumor diameter was 4.85 cm(1-11 cm). Six of the cases(7.8%) had high and 71(92.2%) had low grade. The pT stages of the cases were respectively 3 cases pT1(3.9%), 14 cases pT2(18.2%), 50 cases pT3(65%), 10 cases pT4(12.9%). N stages were pNx in 2 cases(2.6%), pN0 in 57 cases(74%), pN1 in 14 cases (18.2%), and pN2 in 4 cases(5.2%), respectively. ETS preparations were reevaluated. VI was detected after ETS staining in 6(7.8%) of 77 cases.
 Conclusion: As a result, we recommend the application of vessel wall markers such as ETS to all cases without VI on HE sections. Thus, the errors that may occur in the interpretation of VI, which affect the treatment protocol and survival of the patient, will be reduced.

An untapped resource: characteristics of thrombus recovered from intermediate or high risk pulmonary embolus patients

IntroductionResponse to anticoagulation varies during management of acute hospitalized pulmonary embolism. We aimed to study thrombus histology in pulmonary embolism samples removed during acute surgical embolectomy to evaluate whether thrombus morphology was similar between patients and whether there was an association with duration of symptoms and/or resolution on follow up imaging. MethodsThis was a retrospective observational single center study at the University of Rochester Medical Center. We evaluated patients that underwent acute surgical embolectomy and followed up in our clinic 2 – 4 months after the event with Ventilation/Perfusion (V/Q) scan obtained for all regardless of symptoms. Thromboemboli were formalin fixed and processed for light microscopy in the hospital histopathology laboratory. Four-micron thick sections were stained with hematoxylin and eosin, Masson trichrome, and Verhoeff elastic tissue stains. Immunohistochemistry was performed using anti-CD31 and anti-CD68. Slides were independently evaluated for time-dependent microscopic changes using Irniger's classification by two blinded pathologists. ResultsSixteen patients underwent embolectomy with fifteen having V/Q imaging at follow up. The majority of patients were female. Samples showed a generally similar overall architecture that included a central core composed primarily of red blood cells and fibrin and an outer layer of platelets and monocytes. Two samples had evidence of fibrosis and recanalization. ConclusionsWe found heterogeneous histopathology in samples obtained during acute embolectomy. Further prospective studies should systematically characterize clot morphology and evaluate treatment response and outcomes. Careful thrombus specimen measurement and consistent sampling for sections will be required to draw firm conclusions.

Polarized Microscopy Study of 10 Cases of Lichen Sclerosus Using Picro-Sirius Red Stain

Abstract Lichen sclerosus (LS) is a chronic mucocutaneous sclerosis most commonly affecting the genital area, although extragenital localizations have also been described1, with unknown pathogenesis. Our study aims to analyze the morphopathological aspects of LS through the prism of polarized microscopy and with the help of histochemical information provided by special Van Gieson stain for elastic tissue and Picro-Sirius Red special stain. Picro-Sirius Red staining allows observation of the type of collagen synthesized in pathological conditions such as LS, as well as the appearance of mature hyalinization through loss of elastic tissue, and also the disappearing of piloerectile muscles.

The use of special stains in the detection of vascular invasion in cases of colon cancer in resource-limited settings in Africa

Background: Vascular invasion (VI) is a well-established independent prognostic factor in colorectal cancer (CRC) associated with the hematogenous spread and high risk of mortality. Its accurate detection is essential in identifying a high-risk group of patients who may benefit from adjuvant therapy and also to detect the risk of disease recurrence. The aim of the study was to determine the value of an elastic tissue stain in assessing vascular invasion in CRC. Materials and Methods: Formalin-fixed paraffin-embedded histologically confirmed CRC blocks were retrieved from the archives of the Histopathology Department of the Komfo Anokye Teaching Hospital. Duplicate sections were made from each block and divided into two, with one part of the sections stained with hematoxylin and eosin (H and E) and the other with Verhoeff–Van Gieson (VVG) stain. Both H and E and VVG-stained sections were assessed for vascular invasion. Findings were put in tables and charts. Results: Forty-one cases were used for our study, comprising 40 adenocarcinomas (six well differentiated, 26 moderately differentiated, and eight poorly differentiated) and one high-grade non-Hodgkin large cell lymphoma. The mean age of our patient was 55 years, with a male-to-female ratio of 1:1.4. Of the 41 sections stained with H and E, venous invasion (VI) was detected in 14 cases (34%), whereas VVG was detected vascular invasion in 18 cases of the 27 undetected by H and E in addition to all the 14 cases detected by H and E (78%). Conclusion: The application of the VVG elastic tissue stain enhanced the sensitivity of detecting VI as compared to the use of H and E alone, and thus, recommendations should be made to include elastic tissue stains in CRC pathology reporting to bring therapeutic benefits to patients in our environment.

Exogenous Ochronosis as an Elastotic Disease: A Light-Microscopic Approach.

Exogenous ochronosis (EO) is a deposition disease associated with application of hydroquinone-containing preparations. Characteristic ochronotic bodies (OBs) arise from endogenous connective tissues, most often reported as collagen. We highlight a significant role for elastic fibers as a precursor tissue. To evaluate elastic tissue pathology in EO, specifically as it relates a precursor role in ochronotic body formation. In this retrospective observational study, a literature review using PubMed/MEDLINE database was conducted to ascertain the most commonly ascribed precursor connective tissue. Eleven histopathologic cases of EO were identified. Patient demographics and clinical characteristics were recorded. Slides were reviewed for the presence and grade of solar elastosis (SE), the relationship of OBs to elastotic material, the presence of elastotic fibers transitioning to OBs, and positivity of bodies with Verhoeff-van Gieson elastic tissue stain. Elastic fibers are uncommonly reported as the major precursor tissue of OBs. SE was uniformly present in our cases, and the majority demonstrated heavy/high-grade elastosis. Elastotic fibers transitioning to OBs were observed in all cases, and the bodies demonstrated Verhoeff-van Gieson positivity. Small sample size. Ochronotic body formation is associated with SE, and bodies appear to arise from damaged elastic fibers.

Progressive Structural Remodeling of Residual Coronary Arteries in Post‐Myocardial Infarction Scar

We have reported previously that local, patent microvascular networks support long‐term survival of adult cardiac myocytes in subendocardial and subepicardial regions of large transmural post‐myocardial infarction (MI) scars induced by left coronary artery ligation in middle‐aged rats. According to our findings, such microvascular beds become perfused retrogradely from the left ventricular chamber via Thebesian vessels linked to residual veins. However, considering that surviving cardiac myocytes may serve as an endogenous source of contractile cells in healing scars, it is vital to determine whether the original arterial bed can be salvaged as a conduit for blood reperfusion. Therefore, in the current study, we aimed to investigate structural integrity of residual coronary arteries in healing post‐MI scars. In order to achieve this goal, a large transmural MI was induced in 12‐month‐old male Sprague‐Dawley rats by permanent ligation of the left coronary artery. Post‐MI rats were euthanized 4 and 12 weeks after surgery and their hearts were processed into paraffin for histological evaluations. Eight micron transverse sections of each heart were stained with picrosirius red, Masson's trichrome and Verhoeff's elastic tissue stains. In addition, sections were labeled with TUNEL technique and an anti‐smooth muscle (SM) alpha‐actin antibody. Images of stained arteries were captured using an Olympus BX53 microscope equipped with DP72 digital camera. Furthermore, in each heart, the entire scar, stained for fibrillar collagen and SM alpha‐actin, was digitized and then analyzed with Image‐Pro Analyzer v.7.0 software to determine the fractional volumes of intravascular collagen and vascular SM cells. We found that the profiles of residual coronary arteries could be identified clearly in 4‐ and 12‐week‐old scars. Although some vessels appeared normal, most nonperfused arteries revealed gross structural alterations including accumulation of perivascular collagen and a prominent centripetal neointimal growth narrowing the vessel lumen. In the latter case, vascular SM cell hyperplasia was accompanied by a perecellular accumulation of collagen and elastic fibrils. Consistent with the progressive nature of these changes, in 12‐week‐old scars we often observed a complete obliteration of arterial lumens that occurred concurrently with disappearance of vascular SM cells and their replacement by collagenous tissue. The positive TUNEL stain in the walls of residual arteries indicates that the reduction in vascular SM cells might be related to their death via apoptosis. Importantly, our quantitative assessment of 4‐ and 12‐week‐old scars did confirm that the overall dynamic of structural changes observed in residual coronary arteries was associated with progressive accumulation of intravascular collagen (0.52±0.17% vs. 0.80±0.12%, respectively) and reduction in the content of vascular SM cells (2.27±0.51% vs. 1.53±1.19%, respectively). Therefore, our current findings provide additional support for the necessity of earlier reperfusion of the residual coronary arterial bed in healing scars in order to preserve its capacity to serve as a potential conduit for restored blood supply.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Cutaneous Elastic Tissue Anomalies.

After a review of the physiology in the formation and degradation of cutaneous elastic tissue, we describe the clinicopathologic disorders characterized by increased and decreased cutaneous elastic tissue. Cutaneous disorders characterized by increased and/or abnormal elastic tissue in the dermis include elastoma, also named nevus elasticus, dermatosis lenticularis disseminata, pseudoxanthoma elasticum, late-onset focal dermal elastosis, linear focal elastosis, elastoderma, elastofibroma dorsi, and elastosis perforans serpiginosa. In some of these conditions, the specific histopathologic diagnosis may be rendered with hematoxylin-eosin stain, whereas in other ones special elastic tissue stains are necessary to demonstrate the anomalies. Cutaneous disorders characterized by decreased dermal elastic tissue include nevus anelasticus, papular elastorrhexis, perifollicular elastolysis, anetoderma cutis laxa, postinflammatory elastolysis and cutis laxa, white fibrous papulosis of the neck, pseudoxanthoma elasticum-like papillary dermal elastolysis, and mid dermal elastolysis. In most of these conditions, the histopathologic anomalies are only seen with elastic tissue stains, and cutaneous biopsies of these processes stained with hematoxylin-eosin show appearance of normal skin. The diagnosis of some of these disorders characterized by increased or decreased elastic dermal tissue should be followed by general exploration of the patient to rule out associated severe systemic anomalies, and in some cases, a genetic counseling should be offered to the family.

Chronic Heart Rate Reduction by Ivabradine Does Not Modify the Elastic Fiber Content in Post‐Myocardial Infarction Scar of Middle‐Aged Rats

A large myocardial infarction (MI) triggers progressive cardiac remodeling which results in left ventricular (LV) chamber dilatation and, as a consequence, in greater wall tension, particularly in the area of scar formation. Chronically elevated mechanical stress applied to fibroblasts and myofibroblasts within the scar has been known to stimulate the production of extracellular matrix proteins, predominantly collagen and elastin, that improves the tensile strength of the thinning LV wall. Considering that during a prolonged diastole the end‐diastolic volume and, hence, the force and duration of mechanical signals transduced into the scar become even more augmented it is feasible to assume that any heart rate‐lowering agent would promote further deposition of extracellular proteins by activated fibrogenic cells. Nevertheless, we have previously shown that chronic heart rate reduction (HRR) by ivabradine (IVA), a selective inhibitor of a pacemaker If current, did not alter the content of fibrillar collagen in post‐MI scar of middle‐aged rats. However, whether IVA‐induced HRR affects the content of elastic fibers in the scar remains undetermined. To test this hypothesis a large transmural MI (greater than 50% of the LV free wall) was induced in 12‐month‐old male Sprague‐Dawley rats by ligation of the left coronary artery. Post‐MI rats were then assigned in IVA‐treated (MI+IVA) and corresponding placebo (MI) groups. In MI+IVA groups, rats were treated with IVA i.p. via osmotic pumps in a dose of 10.5 mg/kg/d for 8 and 12 weeks. At the end of each treatment period, the hearts were collected and processed into paraffin‐embedded sections for histological evaluations. Eight‐micron‐thick sections of the left ventricle were stained with picrosirius red and Verhoeff's elastic tissue stains. The entire scar of each heart stained for collagen and elastic fibers were digitally captured on a computer using an Olympus BX53 microscope and the fractional volumes of collagen and elastic fibers were determined by using Image‐Pro Analyzer v.7.0 software. We found that the mean scar size and thickness were comparable among all groups of rats. Furthermore, the spatial distribution of the elastic fibers within the scars demonstrated almost identical pattern with an evident accumulation along the subendocardial and subepicardial regions, in the remnants of coronary vessels, and in isolated areas near the edge or throughout the middle portion of the scar. In addition, IVA‐treated and untreated rats showed a similar tendency in reduction of elastic component of the scars that was directly correlated with scar maturation. The quantitative analysis has revealed that the content of elastic fibers remained relatively analogous in scars of MI and MI+IVA rats 8 weeks (1.88±0.36% vs. 1.21±0.31%, respectively) and 12 weeks (0.99±0.45% vs. 0.89±0.18%, respectively) after MI. Moreover, there was no significant difference in ratio between elastic and collagenous components of the scar in corresponding IVA‐treated and untreated groups of rats. Our data are the first to demonstrate that chronic IVA‐induced HRR does not modify the elastic fiber content in post‐MI scar.

Sclerosing Dermatofibrosarcoma Protuberans Shows Significant Overlap With Sclerotic Fibroma in Both Routine and Immunohistochemical Analysis: A Potential Diagnostic Pitfall.

Dermatofibrosarcoma protuberans (DFSP) is an uncommon, low-to-intermediate grade sarcoma with several histologic variants, including pigmented (Bednar tumor), sclerosing, myxoid, atrophic, and DFSP with fibrosarcomatous changes. Two patterns of sclerosis in DFSP can be observed, a sclerotic fibroma-like pattern and a morphea/lichen sclerosus-like pattern. Partial biopsies of sclerosing DFSPs with the sclerotic fibroma pattern can be misdiagnosed as sclerotic fibroma or other benign sclerosing tumors (eg, perineurioma, dermatofibroma). DFSPs from our tissue archives were screened for tumors with a sclerosing pattern, and then studied with epithelial membrane antigen (EMA), CD34, and elastic tissue staining to investigate whether such stains can differentiate sclerosing DFSP from sclerotic fibroma. Ten cases of sclerotic fibroma were similarly studied. Two of the 27 DFSPs were predominantly sclerosing and 5 additional DFSPs had a mixed histopathologic pattern including a sclerosing component. Immunohistochemically, all DFSPs with sclerosing (predominant or mixed) pattern were positive for CD34, and 5/7 were at least focally positive for EMA. Elastic tissue staining was reduced or absent in the sclerotic areas. All cases of sclerotic fibroma were either positive or focally positive for CD34, whereas EMA was focally positive in 5/10. Elastic tissue staining ranged from reduced to totally absent in the sclerotic fibromas. In conclusion, the similar histopathologic and immunophenotypic characteristics in sclerotic fibroma and sclerosing DFSP found in this analysis highlight the importance of obtaining clinical information and potentially additional excision for partial biopsies showing a sclerotic fibroma-like pattern.

Atrophying pityriasis versicolor as an idiosyncratic T cell–mediated response to Malassezia: A case series

Atrophying pityriasis versicolor (PV), first described in 1971, is a rare variant in which lesions appear atrophic. We sought to determine the pathophysiology of atrophying PV. A retrospective chart review identified 6 cases of atrophying PV. In all cases, routine light microscopy, an elastic tissue stain, and immunohistochemical assessment for the expression of CD3, CD4, CD8, GATA3 and CXCR3 was performed. All cases demonstrated hyperkeratosis with intracorneal infiltration by pathogenic hyphal forms as well as epidermal attenuation and papillary dermal elastolysis. A supervening, mild-to-moderate, superficial lymphocytic infiltrate was noted and characterized by a focal CD8+ Tcell-mediated interface dermatitis along with a mixed T-cell infiltrate composed of GATA3+ and CXCR3+ Tcells. Small sample size and the loss of some patients to follow-up. Atrophying PV represents the sequelae of a mixed helper T-cell (TH1 and TH2) idiosyncratic immune response to Malassezia and can present as a protracted dermatosis that may clinically mimic an atypical lymphocytic infiltrate. TH1 cytokines can recruit histiocytes, a source of elastases, and upregulate matrix metalloproteinase activity, which may contribute to epidermal atrophy.

Microscopic venous invasion in patients with pancreatic neuroendocrine tumor as a potential predictor of postoperative recurrence

BackgroundMicroscopic venous and lymphatic invasion is a known prognostic factor for various cancers, but its prognostic relevance for pancreatic neuroendocrine tumors (PNETs) is unclear. MethodsThirty-two consecutive patients with PNET who had complete resection were included in this study. Venous and lymphatic invasion was identified on elastic tissue or immunohistochemical staining, and correlated with other clinicopathological factors, including recurrence-free survival. ResultsVenous and lymphatic invasion was identified in nine (28%) and three (9%) patients, respectively. Tumors with venous invasion were of significantly larger size, higher Ki-67 index, and higher mitotic counts. Patients with venous invasion showed significantly worse prognosis than those without venous invasion (P = 0.001). Five of nine patients (56%) with venous invasion had tumor recurrence, while a relapse was found in one case in patients without venous invasion (n = 23). Lymphatic invasion was not correlated with any other clinicopathological parameters including lymph node metastasis and recurrence-free survival. Predictive factors for recurrence in univariate analysis included microscopic venous invasion, tumor size ≥ 20 mm, non-functionality, and WHO grades. In multivariate analysis where WHO grades and microscopic venous invasion were applied, venous invasion remained a significant predictor of poor recurrence-free survival (P = 0.021). ConclusionsMicroscopic venous invasion may serve as a predictive factor for tumor recurrence in patients with resectable PNET. The combination of WHO grades and microscopic venous invasion may assist in the stratification of the patients for risk of tumor recurrence.

Frequency of cutis laxa-like clinical features and elastolysis in scleromyxedema: a retrospective clinicopathologic study of 19 patients with scleromyxedema.

Cutis laxa-like features were observed in a subset of patients with scleromyxedema. Given this observation, clinical and histopathologic features of scleromyxedema were reviewed in correlation with elastic tissue staining. We retrospectively reviewed clinical records and histopathologic features from patients with scleromyxedema seen at our institution from 1992 through 2013. We also evaluated available skin biopsies with an elastin stain and assessed whether dermal elastin fibers were diminished in density or were fragmented (or both). Nineteen patients with scleromyxedema and 34 skin biopsies were identified. Alcian blue (mucin) stain was used to grade mucin deposition as weakly positive (24%), positive (44%) and markedly positive (32%). Eight patients (42%) had clinical findings of cutis laxa, which were often observed in conjunction with areas of papular eruption or induration. Elastic tissue fibers were normal in 9 of 34 skin specimens (26%), 18 of 34 specimens (53%) had diminished elastic fiber density and 7 of 34 (21%) had markedly decreased density. The elastic tissue was fragmented in 25 specimens (74%). A cutis laxa-like clinical presentation and decreased elastic tissue density on skin biopsy were consistent findings. Dermatologists and dermatopathologists should be aware of these previously unreported clinical and histopathologic findings.

Epithelioid Leiomyosarcoma Arising in the Subcutis—A New Case Report of a Rare Variant

Epithelioid Leiomyosarcoma Arising in the Subcutis—A New Case Report of a Rare Variant

Elastin staining patterns in primary cicatricial alopecia

Most biopsy specimens of cicatricial (scarring) alopecia can be readily subclassified as lymphocytic versus neutrophilic, but specific diagnosis remains difficult, particularly when a late stage of the disease is sampled. We sought to document patterns of scarring highlighted by elastic tissue staining in primary cicatricial alopecia. We documented Verhoeff elastic van Gieson staining patterns in 58 routinely embedded (vertical) biopsy specimens of cicatricial alopecia. Patterns of fibrosis included perifollicular (wedge-shaped vs broad tree trunk-shaped) and diffuse. The patterns were compared against the diagnosis obtained by independent expert clinical review, including central centrifugal cicatricial alopecia (CCCA), lichen planopilaris, traction alopecia, frontal fibrosing alopecia, discoid lupus erythematosus, and tufted folliculitis. Wedge-shaped perifollicular fibrosis was seen in lichen planopilaris but also in CCCA. Broad tree trunk-shaped perifollicular fibrosis was most commonly encountered in CCCA. The retrospective nature of the study precluded temporal staging of the disease process. Patterns of fibrosis highlighted by elastin staining in primary cicatricial alopecia appear to be disease specific. Superficial wedge-shaped perifollicular fibrosis is associated with but may not be specific for lichen planopilaris. Broad tree trunk-like perifollicular fibrosis is specific for CCCA but not present in many cases. Elastin staining represents a useful ancillary study for the evaluation of late-stage scarring alopecia in routinely oriented punch biopsy specimens.

Elastic staining versus fluorescent and polarized microscopy in the diagnosis of alopecia

Recently, polarized microscopy was reported as helpful in the evaluation of alopecia biopsy specimens. We sought to determine the usefulness of polarized microscopy relative to elastic tissue staining and fluorescent microscopy. Histologic sections from 60 alopecia specimens were evaluated to determine the pattern of elastic tissue in elastic van Gieson-stained sections. Comparable hematoxylin-eosin sections were examined under a fluorescent microscope to determine the elastic tissue pattern and examined under polarized microscopy to determine the pattern of birefringence. Elastic van Gieson staining demonstrated high sensitivity (1.0) and high specificity (1.0) for the identification of nonscarring alopecia. In 54 of 60 cases, fluorescent microscopy demonstrated an identical pattern of elastic tissue. High background eosin fluorescence made it impossible to interpret the elastic tissue pattern in the remaining 6 specimens. Strong birefringence in dermal collagen sparing fibrous tracts had high specificity (1.0) but lower sensitivity (0.59). Strong collagen birefringence within the dermis and broad fibrous tracts were present in all 6 cases of central centrifugal cicatricial alopecia. Elimination of the 6 uninterpretable specimens with high background fluorescence from our calculations may be a source of bias, as these cases could potentially all have been either negative or positive. Elastic tissue staining is the most reliable means to determine the pattern of scarring in alopecia biopsy specimens. In most cases, fluorescent microscopy of hematoxylin-eosin sections shows an identical pattern. Although a pattern of collagen birefringence on polarized microscopy distinctly sparing fibrous tract is specific for nonscarring alopecia, not all cases of nonscarring alopecia demonstrate this pattern. Strong collagen birefringence within both the dermis and fibrous tracts suggests a diagnosis of central centrifugal cicatricial alopecia.

Transplantation of human thrombomodulin gene-modified endothelial progenitor cells to prevent vascular restenosis after balloon injury

Objective To explore the feasibility of transplantation of human thrombomodulin (hTM) gene-modified endothelial progenitor cells (EPCs) to rabbit carotid artery balloon injury model locally to prevent vascular restenosis.Methods Rabbit peripheral blood mononuclear cells were isolated and EPCs were modified with hTM gene using X-tremeGENE HP DNA Transfection Reagent.Genetically modified EPCs were incubated with Fe2O3-arginine.Sixteen adult New Zealand white rabbits were divided into two groups.hTM gene-modified EPCs,nom-gene modified EPCs and equal volume of normal saline were transplanted to the balloon injury local via Fogarty balloon catheter,respectively.Serial nuclear magnetic resonance (MRI) was performed on 1st,3rd,7th and 14th day after transplantation to assess the loss of MRI signal intensity at the injured sites.Four months later,the carotid arteries were isolated and cut for hematoxylin and eosin (HE) staining and elastic tissue staining to evaluate restenosis.Results The hTM gene could be successfully transfected into EPCs using Transfection Reagent and the efficiency rate was about 10％-15％.EPCs could be partly adhered to the injured site locally via Fogarty balloon catheter and result in the loss of magnetic resonance (MR) signal intensity at the injured sites.The neointimal/media ratio (N/M) in gene modified group,non-gene modified group and injured group was 0.30 ± 0.02,0.62 ± 0.05 and 1.58 ± 0.10,respectively (P ＜ 0.01).Conclusion hTM gene-modified EPCs could effectively prevent vascular restenosis after balloon injury. Key words: Thrombomodulin; Endothelial progenitor cells; Balloon injury; Restenosis

Elastic Tissue in Nevus Lipomatosus Cutaneous Superficialis

Nevus lipomatosus cutaneous superficialis (NLCS) is a rare benign hamartomatous condition characterized by the presence of mature ectopic adipocytes in the dermis. We studied twelve cases of solitary type of NLCS to demonstrate the status of elastic fibers. All were stained with elastic-van Gieson stain for elastic tissue. Most of the cases showed moderate to marked reduction and thinning of elastic fibers (EF) as compared to adjacent normal dermis. We conclude that thinned and decreased elastic tissue is the cause of NLCS.