Search results for "Epithelial cell"
showing 10 items of 475 documents
Unusual epithelial-myoepithelial carcinoma in palate: case report and immunohistochemical study
2010
Ephitelial-myoepithelial carcinoma (EMC) is a neoplasm of salivary gland extremely rare and low-grade malig- nant, exhibiting predilection for major salivary gland, especially parotid gland. This paper described a case of EMC localized in soft palate. The initial clinical diagnosis were mucoepidermoid and adenoid cystic carcinoma. A incisional biopsy was performed, and the histological diagnosis was adenocarcinoma not otherwise specified. The patient underwent excisional biopsy, where was realized immunohistochemical analysis, staining the duct-like structures, where the inner layer of epithelial cells positively for CK 14, whereas outer layer of myoepithelial cells stained positively for s…
Hepatic progenitors for liver disease: current position
2010
Alice Conigliaro1, David A Brenner2, Tatiana Kisseleva21University “La Sapienza”, Dipartimento di Biotecnologie Cellulari ed Ematologia Policlinico Umberto I, V Clinica Medica, Rome, Italy; 2Department of Medicine, University of California, San Diego, La Jolla, CA, USAAbstract: Liver regeneration restores the original functionality of hepatocytes and cholangiocytes in response to injury. It is regulated on several levels, with different cellular populations contributing to this process, eg, hepatocytes, liver precursor cells, intrahepatic stem cells. In response to injury, mature hepatocytes have the capability to proliferate and give rise to new hepatocytes and cholangi…
Multiple Receptors Mediate apoJ-Dependent Clearance of Cellular Debris into Nonprofessional Phagocytes
2001
Phagocytosis of apoptotic, senescent, and dying cells by macrophages is a well characterized process. More recently it has been shown that in addition to macrophages vital neighboring cells in the affected tissue participate in the cellular clearance. While scavenger receptors have been shown to mediate uptake into macrophages, it is poorly understood how cellular debris is internalized by nonprofessional phagocytes. We here analyze the endocytic activity of vital fibroblasts and epithelial cells exposed to cellular debris and membrane remnants. We show a mutual stimulation in the endocytosis of debris and apolipoproteinJ (clusterin) in these cells. Experiments using RAP (receptor-associate…
Establishment of a pulmonary epithelial barrier on biodegradable poly-L-lactic-acid membranes
2019
Development of biocompatible and functional scaffolds for tissue engineering is a major challenge, especially for development of polarised epithelia that are critical structures in tissue homeostasis. Different in vitro models of the lung epithelial barrier have been characterized using non-degradable polyethylene terephthalate membranes which limits their uses for tissue engineering. Although poly-L-lactic acid (PLLA) membranes are biodegradable, those prepared via conventional Diffusion Induced Phase Separation (DIPS) lack open-porous geometry and show limited permeability compromising their use for epithelial barrier studies. Here we used PLLA membranes prepared via a modification of the…
Subcellular distribution of choline acetyltransferase by immunogold electron microscopy in non-neuronal cells: Placenta, airways and murine embryonic…
2012
Abstract Aims Acetylcholine is synthesized in more or less all mammalian cells. However, little is known about the subcellular location of acetylcholine synthesis. Therefore, in the present experiments the subcellular location of the synthesizing enzyme choline acetyltransferase (ChAT) was investigated by anti-ChAT immunogold electron microscopy in human placenta and airways as well as in a murine embryonic stem cell line (CGR8 cell line). Main methods Human tissue was obtained as so-called surplus tissue (after delivery/surgical removal because of lung tumor); the CGR8 stem cell line was cultured under standard conditions. For human tissue a monoclonal mouse anti-ChAT antibody (ab) was use…
Stem cells, cancer stem-like cells, and natural products.
2012
Somatic stem cells can be found in many rapidly regenerating tissues, e.g., the skin, gastrointestinal mucosa, and hematopoietic system, but are also present at low numbers in non-regenerative organs such as the heart and brain. In these organs, somatic stem cells aid in normal tissue homeostasis and repair after injury as well as self-renewal and the generation of specific progenitor cells during differentiation. Cancer stem-like cells are a small subpopulation of self-renewing cells that are able to proliferate upon appropriate stimulation and differentiate into heterogeneous lineages in tumors. Modulation of the behavior of normal tissue stem cells and cancer stem-like cells is an emergi…
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…
Cationic polyaspartamide-based nanocomplexes mediate siRNA entry and down-regulation of the pro-inflammatory mediator high mobility group box 1 in ai…
2015
Abstract High-mobility group box 1 (HMGB1) is a nonhistone protein secreted by airway epithelial cells in hyperinflammatory diseases such as asthma. In order to down-regulate HMGB1 expression in airway epithelial cells, siRNA directed against HMGB1 was delivered through nanocomplexes based on a cationic copolymer of poly(N-2-hydroxyethyl)- d,l -aspartamide (PHEA) by using H441 cells. Two copolymers were used in these experiments bearing respectively spermine side chains (PHEA-Spm) and both spermine and PEG2000 chains (PHEA-PEG-Spm). PHEA-Spm and PHEA-PEG-Spm derivatives complexed dsDNA oligonucleotides with a w/w ratio of 1 and higher as shown by a gel retardation assay. PHEA-Spm and PHEA-P…
Pore-forming toxins activate MAPK p38 by causing loss of cellular potassium.
2009
Mitogen activated protein kinase (MAPK) p38 has emerged as a survival protein in cells that are attacked by bacterial toxins forming small membrane pores. Activation of p38 by pore forming toxins (PFT) has been attributed to osmotic stress, but here we show that loss of K+ is likely to be the critical parameter. Several lines of evidence support this conclusion: first, osmoprotection did not prevent p38-phosphorylation in alpha-toxin-loaded cells. Second, treatment of cells with a K+ ionophore, or simple incubation in K+-free medium sufficed to cause robust p38-phosphorylation. Third, media containing high [K+] prevented p38-activation by Staphylococcus aureus alpha-toxin, Vibrio cholerae c…
Immunohistochemical expression of glucose transporter 1 in keratin-producing odontogenic cysts
2016
Background: Keratin-producing odontogenic cysts (KPOCs) are a group of cystic lesions that are often aggressive, with high rates of recurrence and multifocality. KPOCs included orthokeratinised odontogenic cyst (OOC) and parakeratotic odontogenic cysts, which are now considered true tumours denominated keratocystic odontogenic tumours (KCOTs). GLUT1 is a protein transporter that is involved in the active uptake of glucose across cell membranes and that is overexpressed in tumours in close correlation with the proliferation rate and positron emission tomography (PET) imaging results. Methods: A series of 58 keratin-producing odontogenic cysts was evaluated histologically and immunohistochemi…