Smooth Muscle Actin Staining Research Articles

Fibrosis in small syngeneic rat liver grafts because of damaged bone marrow stem cells from chronic alcohol consumption.

A patient with liver failure due to chronic and acute alcohol abuse under consideration for an urgent liver transplant shortly after stopping alcohol may have residual abnormalities that threaten transplant success, particularly for a small graft. To address this, we studied a model in which reduced-size (50%) Lewis rat livers are transplanted into green fluorescence protein transgenic Lewis recipients after they are fed alcohol or a control diet for 5 weeks. Here we show that normal small Lewis grafts transplanted to alcohol-fed Lewis hosts developed fibrosis, whereas no fibrosis was observed in control-fed recipients. Host-derived CD133 + 8-hydroxy-2'-deoxyguanosine (8-OHdG) cells were significantly increased in livers recovered from both alcohol-fed and control recipients, but only alcohol-fed recipients demonstrated co-staining (a marker of oxidative DNA damage). α smooth muscle actin (α-SMA) staining, a marker for myofibroblasts, also co-localized with CD133 + cells only in the livers of alcohol-fed recipients. Immunostaining and polymerase chain reaction analysis confirmed that chronic alcohol consumption decreased the proportion of bone marrow stem cells (BMSCs) expressing CD133, c-Kit, and chemokine (C-X-C motif) receptor 4 markers and caused oxidative mitochondria DNA (mtDNA) damage. Culture of CD133 + cells from normal rats with medium containing 3% ethanol for 48 hours resulted in elevated mitochondrial 8-OHdG and mtDNA deletion, and ethanol exposure diminished CD133 expression but dramatically increased α-SMA expression. In conclusion, oxidative mtDNA damage and deletions occur in BMSCs of chronic alcohol-fed recipients, and these damaged cells mobilize to the small liver grafts and become myofibroblasts where they play a key role in the subsequent development of fibrosis. Liver Transplantation 23 1564-1576 2017 AASLD.

Development of Human Umbilical Vessels in The Second Trimester of Pregnancy: Histological, Immunohistochemical and Morphometric Study

Introduction: There are many publications describing structure of full term umbilical vessels, however, few studies in early gestation.Aim: To elucidate changes in microstructure of developing umbilical vessels in the second trimester of pregnancy.Material and Methods: Twelve specimens of human umbilical cords were obtained from legal termination of uncomplicated pregnancies at gestational weeks 13, 16, and 20. Two centimeter segments of the cords were cut near the placenta. Specimens were processed for paraffin blocks, sectioned, and stained with haematoxylin & eosin, Masson Trichrome, Orcein, and Periodic Acid Schiff. Immunohistochemistry for alpha smooth muscle actin & laminin antibodies was performed. Morphometry and image analysis for vascular wall thickness & diameter of lumen, and diameter of umbilical cord were done.Results: Umbilical cord sections revealed two arteries (UA) and one vein (UV) embedded in Wharton’s jelly and covered with amniotic epithelium formed of flat then cuboidal epithelium. Umbilical vessels composed of inner intima and outer media. Endothelium demonstrated areas of damage and adhesion of inflammatory cells. Internal elastic lamina was thin, interrupted initially, double layered, and well-developed finally. Smooth muscle cells (SMCs) migrated from vascular lumen or from media by a process of mesenchymal-endothelial transition to replace injured endothelium. The media was composed of immature SMCs initially (thin (morphometry), non-contractile, non-secretory as proved by different stains and collagen content. Wharton’s jelly spindle shaped mesenchymal cells close to vessels revealed positive staining for alpha smooth muscle actin and contributed to the media to compensate for SMC migration. UAs showed thicker wall, narrower lumen than veins and cord diameter increased significantly at the 20 week.Conclusion: Development of umbilical vessels was the result of a continuous remodeling process initiated by secreted endothelial factors from damaged endothelium that influenced; SMCs of media, stem cells of cord blood and Wharton’s jelly simulating early events of atherosclerosis.

Abstract 184: Adenylate Cyclase Type 9 Promotes Atherosclerosis in Mice

Polymorphisms in the ADCY9 gene, coding for adenylate cyclase type 9, determine atherosclerotic cardiovascular responses to the CETP inhibitor dalcetrapib in patients. ADCY9 is broadly expressed and involved in various immune cell functions and inflammatory responses. Our objective is to determine the role of ADCY9 in the development of atherosclerosis in the absence of CETP. We used 8-12 week-old wild-type (WT, n=25) or Adcy9 -inactivated ( Adcy9 Gt , n=21) male mice. To induce hypercholesterolemia and atherosclerosis, mice were infected with an adeno-associated virus coding for a gain-of-function mutant of Pcsk9 ( Pcsk9 D377Y ) and were fed an atherogenic high-cholesterol diet for 16 weeks in absence or presence of dalcetrapib treatment (200 mg/kg/day). Percent atherosclerotic lesion area (PALA) in the whole aorta was quantified using en face Oil Red O plaque staining. We used VCAM-1 immunofluorescence staining (n=6 per group) in atherosclerotic lesions of the aortic root to quantify inflammation. We also measured aortic root accumulation of macrophages and vascular smooth muscle cells by immunofluorescence imaging of CD68 and smooth muscle actin (SMA), respectively, in plaque lesions. We also quantified blood leukocytes in normocholesterolemic WT and Adcy9 Gt mice by flow cytometry analysis of CD45 + cells. In hypercholesterolemic animals, Adcy9 Gt mice showed a 60% decrease in atherosclerotic lesions (PALA: 2.7±0.5%) compared to WT mice (6.5±0.7%, P<0.01). Dalcetrapib treatment, in these mice without CETP, did not modify significantly the reduction (63%) of PALA in Adcy9 Gt mice (2.9±0.4%) compared to WT (7.6±1.6%, P<0.01). Macrophage content was reduced by 55% from 17.8±2.8% in WT to 7.2%±1.9% in Adcy9 Gt mice (P<0.05), while SMA staining was similar. VCAM-1 expression also tended to be decreased, from 5.7±3.3% in WT to 2.0±0.4% in Adcy9 Gt mice (P=0.0598). CD45 + blood leukocytes were reduced by 35.4% in Adcy9 Gt compared to WT normocholesterolemic mice (P<0.01). Adcy9 inactivation in mice (without CETP) results in large reductions of atherosclerosis and plaque macrophage and in decreased VCAM-1 expression. These results support the ADCY9 genotype-dependent clinical effects of dalcetrapib.

Clinico-pathological correlation of hepatic angiomyolipoma: a series of 23 resection cases.

Angiomyolipomas are rare neoplasms of mesenchymal origin and are derived from perivascular epithelioid cells. They usually develop in the kidney and rarely in the liver. Due to their rarity, most hepatic angiomyolipomas have been misinterpreted as hepatocellular carcinoma (HCC) or other hypervascular liver tumours on imaging studies. We aimed to assess the clinico-pathological correlation of hepatic angiomyolipoma. We identified 23 patients with hepatic angiomyolipoma through an institutional database search. Of 5680 cases of primary liver tumours, 23 (0.4%) had angiomyolipomas (mean age, 43.6 ± 12.4 years; 16 female patients). Hepatitis B virus infection was noted in four patients, whereas a liver mass was incidentally detected on routine health screening in 13 patients. The preoperative diagnoses, before liver biopsy, included HCC in 14, angiomyolipoma in six, focal nodular hyperplasia in two and hepatic adenoma in one patient. Eventually, the preoperative diagnoses were changed to HCC in 12 and hepatic angiomyolipoma in 11 patients. The tumour size was 5.3 ± 4.6 cm, and 22 patients had a single tumour. All tumours exhibited positive findings for human melanoma black-45 and smooth muscle actin staining. During a follow-up period of 52.2 ± 23.7 months, none of the patients exhibited tumour recurrence or mortality. Hepatic angiomyolipoma is a rare form of primary liver tumour and is often misdiagnosed as other hypervascular tumours. Although angiomyolipoma is benign in nature, it also has malignant potential; hence, resection is indicated if the tumour grows or malignancy cannot be excluded. Surgical resection is a definitive curative treatment of hepatic angiomyolipoma.

Intrathoracic glomus tumors and glomangiosarcomas: a clinicopathological and immunohistochemical study of 14 cases with emphasis on anatomic distribution.

Fourteen cases of primary intrathoracic glomus tumor and glomangiosarcoma are presented. The patients were 9 men and 5 women aged 36 to 63years (mean, 49.5years). Clinically, 11 patients presented with nonspecific symptoms including cough, hemoptysis, chest pain, and back pain while 3 patients were asymptomatic. Anatomically, 9 tumors were in an intrapulmonary location, 3 in the mediastinum, and 2 in the trachea. Surgical resection was performed in all cases, and grossly the tumors varied in size from 1.5 to 4.5cm in greatest diameter. Histologically, 12 cases corresponded to glomus tumor characterized by a homogenous proliferation of medium-sized cells with round nuclei and inconspicuous nucleoli and no evidence of mitotic activity or necrosis. In 2 cases, the presence of marked cellular pleomorphism, nuclear atypia, and mitotic activity was more in keeping with a diagnosis of glomangiosarcoma. The 2 glomangiosarcomas were located in the lung, one of which was associated with lymph node metastasis. Immunohistochemical stains for smooth muscle actin were positive in all cases while negative for epithelial, vascular, neuroendocrine, and neural markers. Clinical follow-up showed that all patients with a glomus tumor are alive and well after a period of 12 to 36months after surgical resection. In contrast, the 2 patients with glomangiosarcoma died of tumor 24 and 36months, respectively, after initial diagnosis. The current cases highlight the ubiquitous distribution of these tumors within the thoracic cavity and stress the importance of including these tumors in the differential diagnosis of thoracic neoplasms.

Efficacy of allogeneic mesenchymal stem cell administration in a model of acute ischemic kidney injury in cats

ObjectiveTo evaluate the effects of allogeneic mesenchymal stem cells (MSCs) in a model of ischemic acute kidney injury (AKI). Study designRandomized controlled trial. AnimalsAdult, purpose-bred research cats (n=15) and a historical reference group (n=3). MethodsCats underwent unilateral, in vivo, warm renal ischemia, then intravenous administration of 4 million adipose-derived MSCs, bone marrow-derived MSCs, or fibroblasts (n=5/treatment) 1h after reperfusion. Serum creatinine and blood urea nitrogen concentrations were measured at baseline and days 1 and 6. Urine specific gravity, urine protein to urine creatinine ratio, and glomerular filtration rate were measured at baseline and day 6. Both kidneys were harvested on day 6; histopathology was described and scored and smooth muscle actin was quantified with histomorphometry. A 2-way ANOVA was used to compare time and treatment. Chi square analysis was used to determine the % of cats with at least International Renal Interest Society (IRIS) Grade 1 AKI. ResultsTime, but not treatment, had a significant effect on renal function. No difference was noted in % of cats with IRIS AKI. Significantly fewer mitotic figures were observed in ischemic kidneys that received bone-marrow derived MSCs vs. fibroblasts. No differences in smooth muscle actin staining were noted. ConclusionsThis study did not support the use of allogeneic MSCs in AKI in the regimen described here. Type of renal injury, MSC dose, allogenicity, duration, and route or timing of administration could influence the efficacy MSCs.

Sclerosing Microcystic Adenocarcinoma of the Head and Neck Mucosa: A Neoplasm Closely Resembling Microcystic Adnexal Carcinoma.

Microcystic adnexal carcinoma (MAC) occurs predominantly in the centrofacial skin and has been only rarely reported in mucosal surfaces. We here present a 5 case series of tumors closely resembling MAC occurring in the mucosal surfaces of the head and neck, which we have termed sclerosing microcystic adenocarcinomas. These tumors showed a predilection for women (4:1) with an average patient age of 52.6years (range 41-73years). Location included the tongue (n=2), the floor of the mouth (n=2), and the nasopharynx/clivus (n=1). One occurred after radiation therapy and another occurred in the setting of immune compromise. Immunohistochemistry highlighted a dual cell population with luminal cells showing positivity for high and low-molecular weight keratins and surrounding myoepithelial cells showing S100 and smooth muscle actin staining. No cases had nodal involvement, and the single patient with clinical follow-up was alive and free of disease 34months after diagnosis and definitive radiochemotherapy. Differential diagnoses for all cases diverged from those provoked by MAC in the skin and included a variety of salivary gland neoplasms such as adenoid cystic carcinoma, polymorphous low gradeadenocarcinoma, and mucoepidermoid carcinoma. Recognition of sclerosing microcystic adenocarcinoma in the head and neck mucosa is critical given its bland appearance and subtle infiltration pattern, infrequency of nodal involvement, and behavioral differences from the other entities on the differential.

Magnetic Resonance Imaging Identifies Differential Response to Pro-Oxidant Chemotherapy in a Xenograft Model

Induction of oxidative stress is a key component of cancer therapy. Pro-oxidant drugs have been demonstrated to enhance the efficacy of radiotherapy and chemotherapy. An emerging concept is that therapeutic outcomes are dictated by the differential redox buffering reserve in subpopulations of malignant cells, indicating the need for noninvasive biomarkers of tumor redox that can be used for dose identification and response assessment in a longitudinal setting. Magnetic resonance imaging (MRI) enhanced with the thiol-binding contrast agent Gd-LC6-SH, and hemodynamic response imaging (HRI) in combination with hypercapnia and hyperoxia were investigated as biomarkers of the pharmacodynamics of the small molecule pro-oxidant imexon (IMX). Human multiple myeloma cell lines 8226/S and an IMX-resistant variant, 8226/IM10, were established as contralateral tumors in SCID mice. T1slope, an MRI measure of the washout rate of Gd-LC6-SH, was significantly lower post-IMX therapy in 8226/S tumors compared with vehicle controls, indicating treatment-related oxidization of the tumor microenvironment, which was confirmed by analysis of tumor tissue for thiols. T1slope and ex vivo assays for thiols both indicated a more reduced microenvironment in 8226/IM10 tumors following IMX therapy. HRI with hypercapnia challenge revealed IMX inhibition of vascular dilation in 8226/S tumors but not 8226/IM10 tumors, consistent with decreased immunohistochemical staining for smooth muscle actin in treated 8226/S tumors. MRI enhanced with Gd-LC6-SH, and HRI coupled with a hypercapnic challenge provide noninvasive biomarkers of tumor response to the redox modulator imexon.

Sa1368 Generation of a Human Oesophageal Tissue Culture Model From Forceps Biopsies

Introduction Barrett’s oesophagus is the condition whereby the normal stratified squamous epithelium at the lower oesophagus is replaced with simple columnar epithelium in the context of gastro-oesophageal reflux disease. This increases the risk of oesophageal adenocarcinoma (OA) ten-fold, and the majority of people diagnosed with OA do not survive for 12 months. Our understanding of the molecular and cellular mechanisms underlying Barrett’s oesophagus is hindered due to lack of at a suitable model. We set out to develop a model from explant tissue biopsies of adult human oesophagus, as opposed to murine models (mice have a keratinised oesophageal epithelium and do not get Barrett’s oesophagus) or the use of cell lines (which do not recapitulate the normal tissue). Method We devised a study protocol and secured ethical approval (REC reference number 13/YH/0197) to obtain forceps biopsy specimens from consenting adults attending for routine diagnostic gastroscopies at the Royal United Hospital Bath. Specimens were then transported to the University of Bath where we have tested multiple culture conditions. These include choice of culture media, substrate (eg glass, plastic – coated or uncoated, semi-permeable membrane at air/liquid interface), cell adhesion factors (eg collagen I, collagen IV, fibronectin, Matrigel®), choice of tissue preparation (enzyme treatment with dispase in the absence or presence of trypsin, dissection with scissors or minced with a blade), plating density, media volume and use of a cell feeder layer. Results We have recruited 42 participants to date and attempted tissue culture on 36 of these. (Biopsies from 6 patients have been processed for RNA analysis.) Over time we have gradually optimised culture conditions. Of the most recent 6 participants, 5 have cultured successfully with cell survival for at least 14 days. Explant colony growth had been particularly vigorous (>12 mm) when plated on Matrigel® and a feeder layer cell line (mitomycin C-inactivated mouse embryonic fibroblast (iMEF) cell line 3T3-Swiss albino, ATCC® CCL-92™) on plastic coverslips. Explants have also adhered and cultured successfully on collagen IV-coated (sc-29010, Santa Cruz Biotech) plastic coverslips without a feeder layer. Explant colonies were fixed/permeabalised before immunofluorescent staining was performed for cytokeratin 14 (K14), smooth muscle actin (SMA), p63, E-cadherin and SLUG antigens. iMEFs are clearly delineated with SMA staining and the explant outgrowths are positive for K14, p63, E-cadherin and SLUG. Conclusion It is possible to culture adult human oesophageal tissue in vitro from standard pinch-biopsy forceps specimens at gastroscopy and we are in the final stages of optimising conditions, confirming characterisation by repeating experiments and devising a protocol. Disclosure of interest None Declared.

Pseudorosette-Like Proliferations of the Endometrium.

The endometrium displays a wide spectrum of appearances in both neoplastic and non-neoplastic tissue. Unusual proliferations are not infrequently encountered and may lead to misinterpretation. In this study, we investigated pseudorosette-like proliferations (PLPs) found within the endometrial stroma which, to our knowledge, have not been previously reported. Nineteen endometrial samples with PLPs were identified over a period of 5 yr. Characteristics of the endometrium in which the PLPs were arising as well as patient information were recorded for each case. In addition, residual tissue from 10 of the cases was immunostained for cytokeratin, CD10, smooth muscle actin, S-100, and caldesmon to better characterize the lesions. In all cases the endometrium was in the proliferative phase and none of the patients reported the use of exogenous hormones. In 89% (17 of 19) of the cases, PLPs were present as a single focus; 2 cases showed multiple PLPs. Of the 10 immunostained cases, 90% (9 of 10) showed strong/diffuse staining for smooth muscle actin. Six cases showed negative or weak (1+) staining for CD10, whereas 3 showed moderate (2+) and 1 showed strong (3+) staining. In all cases the PLPs were negative for cytokeratin AE1/AE3, S-100, and caldesmon. These studies suggest that PLPs are benign proliferations with smooth muscle differentiation.

Hepatic Angiomyolipoma

Introduction: Comprehensive analysis is essential in determining the appropriate etiology of clinical manifestations. Pathological analysis and immunohistochemistry can differentiate hepatic angiomyolipoma (AML), a rare yet benign tumor, from other more common liver lesions. Case Description: A 62-year-old male with human immunodeficiency virus and Hepatitis B presented with epigastric pain, nausea, and a 30 pound weight loss over 6 months. Physical examination was significant for mild epigastric and right upper quadrant tenderness. Computed tomography (CT) of the abdomen and pelvis revealed a large, well defined heterogeneous mass of the right hepatic lobe measuring 9.6cm in maximal diameter, with vascular soft tissue intermixed with macroscopic fat. Radiologic differentials included a primary hepatic neoplasm such as hepatocellular carcinoma or hepatic AML. Magnetic resonance imaging (MRI) of the liver with triple phase contrast was performed and the lesion remained suspicious for hepatocellular carcinoma. AFP was 3.7 (normal <8.5 ng/mL). A percutaneous CT-guided biopsy of the mass was performed. Histology showed large cells with eosinophilic and fibrillar cytoplasm, admixed with adipocytes, inflammatory cells and extramedullary hematopoiesis consistent with a hepatic AML. This was confirmed with positive staining for smooth muscle actin, Melan-A and HMB-45. Given the size of the AML and the symptoms, the patient underwent open excision of the mass with partial right hepatic lobectomy. Intraoperatively, the lesion was found to be encapsulated. The resected mass was 9.3 x 7.4 x 4.3cm in size and histology confirmed the initial biopsy findings. There were no postoperative complications and he remained symptom free at his follow-up appointment.Figure 1Figure 2Figure 3Discussion: Hepatic AML is a benign mesenchymal tumor composed of variable proportions of smooth muscle cells, adipocytes, and blood vessels. It is most often a solitary tumor found incidentally, although a minority present with upper abdominal discomfort related to mass effect. MRI is considered to be the imaging study of choice but has been reported to misdiagnose between 48-90% of cases given variability in tumor composition. They can be mistaken for hepatocellular carcinoma, hemangioma or hepatic adenoma. Definitive diagnosis is dependent on tissue histopathology and immunostaining for muscle-specific markers such as smooth muscle actin as well as melanoma markers HMB-45 and melan-A.

Unilateral Renal Ischemia as a Model of Acute Kidney Injury and Renal Fibrosis in Cats.

The objectives of this study were to define the acute and chronic effects of 1-hour unilateral in vivo renal ischemia on renal function and histology in cats. Twenty-one adult purpose-bred research cats were anesthetized, and 1 kidney underwent renal artery and vein occlusion for 1 hour. Serum creatinine and urea concentrations, urine protein:creatinine ratio, urine-specific gravity, glomerular filtration rate, hematocrit, platelet concentration and function, and white blood cell count were measured at baseline and variable time points after ischemia. Renal histopathology was evaluated on days 3, 6, 12, 21, 42, and 70 postischemia; changes in smooth muscle actin and interstitial collagen were examined. Following ischemia, whole animal glomerular filtration rate was significantly reduced (57% of baseline on day 6; P < .05). At the early time points, the ischemic kidneys exhibited severe acute epithelial necrosis accompanied by evidence of regeneration of tubules predominantly within the corticomedullary junction. At later periods, postischemic kidneys had evidence of tubular atrophy and interstitial inflammation with significantly more smooth muscle actin and interstitial collagen staining and interstitial fibrosis when compared with the contralateral control kidneys. This study characterizes the course of ischemic acute kidney injury in cats and demonstrates that ischemic acute kidney injury triggers chronic fibrosis, interstitial inflammation, and tubular atrophy in feline kidneys. These late changes are typical of those observed in cats with naturally occurring chronic kidney disease.

PTH-166 Generation of a human oesophageal tissue culture model from forceps biopsies

<h3>Introduction</h3> Barrett’s oesophagus is the condition whereby the normal stratified squamous epithelium at the lower oesophagus is replaced with simple columnar epithelium in the context of gastro-oesophageal reflux disease. This increases the risk of oesophageal adenocarcinoma (OA) ten-fold, and the majority of people diagnosed with OA do not survive for 12 months. Our understanding of the molecular and cellular mechanisms underlying Barrett’s oesophagus is hindered due to lack of at a suitable model. We set out to develop a model from explant tissue biopsies of adult human oesophagus, as opposed to murine models (mice have a keratinised oesophageal epithelium and do not get Barrett’s oesophagus) or the use of cell lines (which do not recapitulate the normal tissue). <h3>Method</h3> We devised a study protocol and secured ethical approval (REC reference number 13/YH/0197) to obtain forceps biopsy specimens from consenting adults attending for routine diagnostic gastroscopies at the Royal United Hospital Bath. Specimens were then transported to the University of Bath where we have tested multiple culture conditions. These include choice of culture media, substrate (eg glass, plastic – coated or uncoated, semi-permeable membrane at air/liquid interface), cell adhesion factors (eg collagen I, collagen IV, fibronectin, Matrigel®), choice of tissue preparation (enzyme treatment with dispase in the absence or presence of trypsin, dissection with scissors or minced with a blade), plating density, media volume and use of a cell feeder layer. <h3>Results</h3> We have recruited 42 participants to date and attempted tissue culture on 36 of these. (Biopsies from 6 patients have been processed for RNA analysis.) Over time we have gradually optimised culture conditions. Of the most recent 6 participants, 5 have cultured successfully with cell survival for at least 14 days. Explant colony growth had been particularly vigorous (&gt;12 mm) when plated on Matrigel® and a feeder layer cell line (mitomycin C-inactivated mouse embryonic fibroblast (iMEF) cell line 3T3-Swiss albino, ATCC® CCL-92™) on plastic coverslips. Explants have also adhered and cultured successfully on collagen IV-coated (sc-29010, Santa Cruz Biotech) plastic coverslips without a feeder layer. Explant colonies were fixed/permeabalised before immunofluorescent staining was performed for cytokeratin 14 (K14), smooth muscle actin (SMA), p63, E-cadherin and SLUG antigens. iMEFs are clearly delineated with SMA staining and the explant outgrowths are positive for K14, p63, E-cadherin and SLUG. <h3>Conclusion</h3> It is possible to culture adult human oesophageal tissue <i>in vitro</i>from standard pinch-biopsy forceps specimens at gastroscopy and we are in the final stages of optimising conditions, confirming characterisation by repeating experiments and devising a protocol. <h3>Disclosure of interest</h3> None Declared.

Nodular fasciitis: a retrospective study of 272 cases from China with clinicopathologic and radiologic correlation.

Our aim is to describe the largest series of nodular fasciitis (NF) with emphasis on the clinicopathologic and radiologic correlation. A total of 272 cases of NF were diagnosed between 2004 and 2014 at our institution. There were 160 males and 112 females with age ranging from newborn to 77 years (mean, 36 years). The upper extremity was the most common location (34%), followed by the head and neck region (24%), trunk (21%), and lower extremity (14%). By radiology, the lesion appeared as well-defined homogeneous mass with low or isodensity on computed tomography, homogenous hypointense or isointense on T1-weighted sequences, and heterogeneous intermediate-to-high signal on T2-weighted sequences. Although all cases were composed of short intersecting fascicles of uniform plump spindle cell, the cellularity and stromal components varied considerably between different cases. In intramuscular or deeply seated NFs, extension into adjacent skeletal muscles or structures was often noted. Immunohistochemically, all cases showed diffuse staining for smooth muscle actin and calponin, with consistent negativity for desmin, h-caldesmon, and β-catenin. Of patients with available followed up information, only 1 experienced local recurrence due to incomplete excision. Our comprehensive study further demonstrated that NF had a wide clinicopathologic spectrum. Correlation with the radiologic features may help pathologists in arriving at an accurate diagnosis.

Smooth Muscle Actin (SMA1) Stain Lungs and Heart on a Strain of CUX‐1 Transgenic mice

Cux‐1 is a gene controlling G1‐S phase by repressing cyclin‐kinase inhibitors p21 and p27. CUX mice develop fibrotic damage in kidneys, testis, and liver by aberrant repression of p27. These mice showed pulmonary inflammation, vasculitis, bronchitis, bronchiectasis, and fibrosis (trichrome staining) in the bronchial basal membrane and arterial media. The heart shows inflammation, small myocardial infarctions, and a reduction of the lumen patency of coronary arteries with increase of media thickness.For fibrosis, the expression of the same conditions in lungs and heart are reported by using SMA stain. Wild type mice were controls. An average of 7 photographs at 400x were taken on both organs of each mouse.Histopathologically, with SMA1 stain, damage was present in lungs with staining in the bronchial musculature, epithelium, and media of small caliber arteries, and alveolar septa.Measurement of lumen patency of lung arteries of CUX1 mice indicated a significant reduction of their lumena. Adventitia showed fibroblasts and macrophages. The myocardium showed presence of macrophages in the myocardial fibers, coronary vasculitis with a reduced lumen patency.In conclusion, SMA1 staining, another indicator of fibrosis was seen in both lungs and heart of these mice. Differences in the thickness of these arteries, especially the adventitia was seen when SMA1 stain was compared to H&amp;E. Little amount of collagen was seen in the coronary arteries of the mice, while present in lung vessels. No collagen was seen in the coronary arteries of controls.

Development of the Ventricular Conduction System of the Crocodilian Heart

Unlike other cold‐blooded vertebrates, crocodilians have a fully septated heart, similar to birds and mammals. It is not known whether they have a ventricular conduction system (VCS) as wellWe studied a group of 8 embryos of the Siamese and Mugger Crocodile between 3 and 84 days of incubation, and serial early embryo sections with HNK‐1/Hematoxylin staining of the Nile Crocodile. We employed optical mapping, ultrasound biomicroscopy, histo‐ and immunohistochemistry, in situ hybridization and 3D reconstructionAt the pre‐septation stage (12 days of incubation), the ventricular activation pattern progressed in a left‐to‐right sweep, similar to that observed at early stages of avian and mammalian cardiogenesis. At two post‐septation stages investigated (45 and 84 days) , epicardial activation patterns showed dual apical breakthroughs on either side of the interventricular septum. Immunohistochemistry using smooth muscle actin (SMA), sarcomeric actin, periostin and HNK‐1 antibodies showed that myocardial SMA staining was present even after septation, while it disappears in comparable chick or mouse hearts. HNK‐1 staining was prominent in the interventricular septum, similar to the situation in the chick and rat where it is considered a marker of the developing ventricular conduction system. In situ hybridization for Cx40 (VCS marker) showed a uniform expression in the entire trabeculated myocardiumWe conclude that this is an evidence of evolutionary correlation between ventricular septation and presence specialized VCS in vertebratesSupported by PRVOUK P35/LF1/5.

Fat embolism sensitizes rats to a “second hit” with lipopolysaccharide

Pulmonary fat embolism (FE) in patients after major bone fracture and other trauma may lead to acute respiratory distress, but few clinical evidence of lung injury remains, and there is a dearth of histopathologic information after the initial recovery. We recently reported histologic changes in the lungs of a patient who died after cesarian delivery, which were similar to a rat model of FE. In this model, we found that despite an apparent full recovery, modest fibrotic damage persisted up to 6 weeks. We tested whether at that time, an additional insult could exacerbate the effects. Triolein (0.2 mL intravenously administered) was given to 18 rats and saline to 18 controls. Six weeks later, each group received (intraperitoneal) lipopolysaccharide (LPS, 3 mg/kg; n = 9) or saline (n = 9). At necropsy 48 hours later, lungs and organs were harvested for study. Lung parenchymal, vascular, and bronchial damage was scored by two pathologists and by Image J analysis. Animals given LPS after triolein showed reduced pulmonary arterial medial diameters compared with those that received LPS alone (p < 0.04). Lung small arterial patency (lumen) was reduced after triolein and even more after combined LPS and triolein (p = 0.018). Triolein increased fibrotic markers (trichrome and smooth muscle actin staining), and this was more severe after LPS. At 6 weeks, fat droplets remained in the lungs, localizing to the subpleural septa. These were smaller and more widespread after LPS. This report describes an animal model to study exacerbation of lung histopathology induced by FE using a known pulmonary toxicant, LPS (a "second hit"). Vascular and fibrotic lung damage was more severe when LPS was given to rats 6 weeks after triolein compared with LPS alone. FE rendered the lungs extra sensitive to a second hit long after apparent clinical recovery. This experimental model of fat embolism provides useful informations for the treatment of patients suffering for similar conditions.

Histomorphometric analysis of collagen architecture of auricular keloids in an Asian population.

Keloids are a pathologic condition of the reparative process, which present as excessive scar formation that involves various cells and cytokines. Many studies focusing on the histologic feature of keloids, however, have shown discordant results without consideration of architectural aspect of collagen structure. The purpose of this study was to demonstrate a schematic illustration of collagen architecture of keloids, specifically auricular keloids, and to analyze each part on the histomorphologic and morphometric basis. Thirty-nine surgically excised auricular keloids were retrieved from the file of Kangbuk Samsung Hospital. After exhaustive histomorphologic analysis, 3 distinctive structural parts, keloidal collagen, organizing collagen, and proliferating core collagen, were identified and mapped in every case. Cellularity of fibroblasts, blood vessel density, degree of inflammatory cell infiltration, and mast cells counts using Masson trichrome stain, Van Gieson stain, toluidine blue stain, and immunohistochemical stains for CD31 and smooth muscle actin were analyzed in each part of each case. Morphometric analysis on these parameters using ImageJ software was performed using 3 representative images of each part. Three parts were histomorphologically distinct by shape and array of collagen bundles, fibroblasts cellularity, blood vessel density, degree of inflammatory cells, and mast cell infiltration. Morphometric analysis revealed statistically significant difference between each part in fibroblasts cellularity, blood vessel density, degree of inflammatory cell infiltration, and mast cells count. All parameters were exceedingly high in whorling hypercellular fibrous nodules in proliferating core collagen showing simultaneous changes in other parts. Morphologically and morphometrically, 3 distinctive parts were identified in auricular keloids. Mast cell infiltrations, blood vessel density, and fibroblast cellularity are simultaneously increased or decreased according to these parts. Proliferating core collagen might serve as a proliferating center of keloids and might be a key portion for tumor growth and recurrence.

Clinicopathologic observation of adenoid cystic carcinoma of esophagus

To study the clinicopathologic features and differential diagnosis of adenoid cystic carcinoma in the esophagus. Ten cases of primary adenoid cystic carcinoma of the esophagus were retrieved from the archival file. The clinicopathologic and immunohistochemical features were studied. The differential diagnosis was analyzed. The male-to-female ratio was 9: 1. The age of patients ranged from 59 to 76 years. There were 4 cases with tumor located in mid esophagus, 4 cases with tumor located in mid to lower esophagus and the remaining 2 cases in lower esophagus. Low-power histologic examination showed mainly expansive growth pattern, with cribriform, solid and focal tubular architectures identified. The tumor cells showed nuclear hyperchromasia. Both ductal and myoepithelial differentiation was demonstrated. The stroma showed myxoid degeneration in areas. Comedo-type necrosis was observed in 8 cases and moderate to severe squamous dysplasia was present in one case. Three cases showed focal areas of squamous cell carcinoma. Immunohistochemical study showed that the tumor cells were positive for p63 (10/10), CD117 (10/10) and S-100 protein (9/10). There was focal staining for calponin (2/10) and smooth muscle actin (2/10). The ductal structures expressed CK7 (10/10). Adenoid cystic carcinoma of the esophagus demonstrates unique morphologic features with expression of S-100 protein and consistent expression of CD117. The above characteristics help to distinguish this entity from basaloid squamous cell carcinoma, mucoepidermoid carcinoma and small cell carcinoma of the esophagus.

MicroRNA-34a Promotes Hepatic Stellate Cell Activation via Targeting ACSL1.

BackgroundThe incidence of liver fibrosis remains high due to the lack of effective therapies. Our previous work found that microRNA (miR)-34a expression was increased, while acy1-CoA synthetase long-chain family member1 (ACSL1) was decreased, in a dimethylnitrosamine (DNS)-induced hepatic fibrosis rat model. We hypothesized that miR-34a may play a role in the process of hepatic fibrosis by targeting ACSL1.Material/MethodsFrom days 2 to 14, cultured primary hepatic stellate cells (HSCs) underwent cell morphology, immunocytochemical staining, and quantitative reverse transcription PCR (RT-qPCR) for alpha smooth muscle actin (α-SMA), desmin, rno-miR-34a, and ACSL1 expression. Wild-type and mutant luciferase reporter plasmids were constructed according to the predicted miR-34a binding site on the 3′-untranslated region (UTR) of the ACSL1 mRNA and then transfected into HEK293 cells. rno-miR-34a was silenced in HSCs to confirm that rno-miR-34a negatively regulates ACSL1 expression. mRNA and protein expression of α-SMA, type I collagen, and desmin were assayed in miR-34a-silenced HSCs.ResultsHSCs were deemed quiescent during the first 3 days and activated after 10 days. rno-miR-34a expression increased, and ACSL1 expression decreased, from day 2 to 7 to 14. rno-miR-34a was shown to specifically bind to the 3′-UTR of ACSL1. miR-34a-silenced HSCs showed higher ACSL1and lower α-SMA, type I collagen, and desmin expression than that of matching negative controls and non-transfected cells.ConclusionsmiR-34a appears to play an important role in the process of liver fibrosis by targeting ACSL1 and may show promise as a therapeutic molecular target for hepatic fibrosis.