Search results for "mucin"
showing 10 items of 189 documents
Clinical, dermoscopic, and histologic aspects of two cases of cutaneous focal mucinosis*
2019
Abstract: Cutaneous mucinoses are a complex and diverse group of connective tissue disorders characterized by the accumulation of mucin and/or glycosaminoglycan in the skin and adnexa. Cutaneous focal mucinosis appears as a solitary, asymptomatic, skin-colored to white papule, nodule, or plaque located anywhere on the body or in the oral cavity. It presents mainly in adults and is characterized on histopathology by mucin throughout the upper and mid dermis. We describe the dermoscopy of two cases of cutaneous focal mucinosis. Both lesions presented a nonspecific homogenous whitish pattern; the first case also exhibited a sharply demarcated yellow border.
Limitations of Immunohistochemistry in Diagnosis of a Primary Mucinous Carcinoma of the Skin and Its Metastasis
2020
We describe the case of a 67-year-old female patient who presented with an unclear swelling on the right supraclavicular neck, two years after resection of a mucinous carcinoma on the right mastoid. Two pathological reports from separate universities diagnosed the primary mastoid skin lesion as a metastatic adenocarcinoma. Strikingly, GATA binding protein 3 (GATA3) and mammaglobin, both immunomarkers found in breast cancer, were positive. An urgent search for the primary tumor most likely in the breast was commenced. However, as no other primary tumor could be detected at that time, a Primary Mucinous Carcinoma of the Skin (PMCS) was also debated. Two years later neck node enlargement was s…
Development of polymer-based nanoparticles for Zileuton delivery to the lung : PMeOx and PMeOzi surface chemistry reduces interactions with mucins
2021
In this paper, two amphiphilic graft copolymers were synthesized by grafting polylactic acid (PLA) as hydrophobic chain and poly(2-methyl-2-oxazoline) (PMeOx) or poly(2-methyl-2-oxazine) (PMeOzi) as hydrophilic chain, respectively, to a backbone of α,β-poly(N-2-hydroxyethyl)-D,L-aspartamide (PHEA). These original graft copolymers were used to prepare nanoparticles delivering Zileuton in inhalation therapy. Among various tested methods, direct nanoprecipitation proved to be the best technique to prepare nanoparticles with the smallest dimensions, the narrowest dimensional distribution and a spherical shape. To overcome the size limitations for administration by inhalation, the nano-into-micr…
Biodegradable and pH-sensitive hydrogels for potential colon-specific drug delivery: Characterization and in vitro release studies
2008
A novel pH-sensitive and biodegradable composite hydrogel, based on a methacrylated and succinic derivative of dextran, named Dex-MA-SA, and a methacrylated and succinic derivative of alpha,beta-poly( N-2-hydroxyethyl)- DL-aspartamide (PHEA), named PHM-SA, was produced by photocross-linking. The goal was to obtain a colon-specific drug delivery system, exploiting both the pH-sensitive behavior and the colon-specific degradability. The hydrogel prepared with a suitable ratio between the polysaccharide and the polyaminoacid was characterized regarding its swelling behavior in gastrointestinal simulated conditions, chemical and enzymatic degradability, interaction with mucin, and cell compatib…
Proteomic characterization of the mucosal pellicle formed in vitro on a cellular model of oral epithelium
2020
The oral mucosal pellicle is a thin lubricating layer generated by the binding of saliva proteins on epithelial oral cells. The protein composition of this biological structure has been to date studied by targeted analyses of specific salivary proteins. In order to perform a more exhaustive proteome characterization of pellicles, we used TR146 cells expressing or not the transmembrane mucin MUC1 and generated pellicles by incubation with human saliva and washing to remove unbound proteins. A suitable method was established for the in vitro isolation of the mucosal pellicle by "shaving" it from the cells using trypsin. The extracts, the washing solutions and the saliva used to constitute the…
The role of mucin 1 in respiratory diseases
2020
Recent evidence has demonstrated that mucin 1 (MUC1) is involved in many pathological processes that occur in the lung. MUC1 is a transmembrane protein mainly expressed by epithelial and hematopoietic cells. It has a receptor-like structure, which can sense the external environment and activate intracellular signal transduction pathways through its cytoplasmic domain. The extracellular domain of MUC1 can be released to the external environment, thus acting as a decoy barrier to mucosal pathogens, as well as serving as a serum biomarker for the diagnosis and prognosis of several respiratory diseases such as lung cancer and interstitial lung diseases. Furthermore, bioactivated MUC1-cytoplasmi…
Mucus and MUC in asthma.
2005
Asthma is characterized by chronic airway inflammation and a mucus hypersecretory phenotype comprising excess mucus secretion, goblet cell hyperplasia and submucosal gland hypertrophy. This augmented mucus secretion has been relatively undervalued in asthma compared with airway inflammation. However, mucus plugging contributes to airflow limitation and airway hyperresponsiveness, and to morbidity and mortality in asthma. We review recent contributions to this field and therapeutic avenues to control mucus hypersecretion.A distinct mucus hypersecretory phenotype may present in asthma. Overexpression of MUC5AC, MUC5B and MUC2 have been described in asthma secretions, but identification of def…
Aclidinium inhibits cholinergic and tobacco smoke-induced MUC5AC in human airways.
2010
Mucus hypersecretion and mucin MUC5AC overexpression are pathological features of chronic obstructive pulmonary disease (COPD). This study examines the inhibitory effect of aclidinium, a new long-acting muscarinic antagonist, on MUC5AC expression in human airway epithelial cells. MUC5AC mRNA (RT-PCR) and protein expression (ELISA and immunohistochemistry) were studied in human bronchial tissue and differentiated human airway epithelial cells activated with carbachol (100 μM) or cigarette smoke extract in the absence or presence of aclidinium. Carbachol increased MUC5AC mRNA and protein expression in human bronchus and cultured epithelial cells. Aclidinium inhibited the carbachol-induced MUC…
Cystic mucinous adenocarcinoma of the lung: a case report.
2011
Abstract Mucinous cystic tumors of the lung are uncommon, the preoperative pathologic diagnosis is difficult and their biological behavior is still controversial. We report the case of a patient with a clinically benign cystic lesion that post-operatively showed to be consistent with an invasive adenocarcinoma arising in a mucinous cystadenoma of the lung, We underline the difficulty of the clinical pre-operative diagnosis of this cystic neoplasia radiologically mimicking a hydatid cyst, and we report the negative TTF1 immunostaining potentially misleading in the differential diagnosis with metastatic mucinous carcinomas. Finallly, we evidence the presence of a pre-existing mucinous benign …