scholarly journals Photosensitization to ultraviolet irradiation and selective killing of cells following uptake of pyrene-containing fatty acid

1986 ◽  
Vol 85 (1) ◽  
pp. 149-159
Author(s):  
E. Fibach ◽  
O. Morand ◽  
S. Gatt
Keyword(s):  
Fatty Acid ◽  
Ultraviolet Irradiation ◽  
Plasma Membranes ◽  
Incubation Temperature ◽  
Serum Proteins ◽  
Neutral Lipids ◽  
Cell Types ◽  
Dodecanoic Acid ◽  
A Cell ◽  
The Individual

Cells were incubated with 12-(1-pyrene)-dodecanoic acid (P12), a long-chain fatty acid to which a pyrene ring has been attached covalently. This acid was transported across the plasma membranes of cells and subsequently incorporated into their neutral lipids and phospholipids. Irradiation of these pyrene-containing cells for short periods (0.5-4 min) with ultraviolet light at 366 nm resulted in eventual cell death. Similar irradiation had no effect on cells that had not been exposed to P12. The time of the period of irradiation necessary for inducing the toxic process was related to the quantity of P12 incorporated, the latter being a function of the respective metabolic activity of the individual cell type. The degree of incorporation of P12 into a cell, and consequently its acquired sensitivity to killing by ultraviolet irradiation at 366 nm, was affected by the incubation temperature and addition of non-fluorescent fatty acid, albumin or other serum proteins. Different degrees of incorporation of P12 into various cell types were used for selective killing and elimination of cell populations by irradiation at 366 nm. The combined procedure of preincubation with P12 followed by ultraviolet irradiation thus permitted selection of cell types with a greater resistance to this procedure.

scholarly journals Evidence for phospholipases from Trypanosoma cruzi active on phosphatidylinositol and inositolphosphoceramide

1999 ◽  
Vol 345 (1) ◽  
pp. 77-84 ◽  
Author(s):  
Laura E. BERTELLO ◽  
Maria Júlia M. ALVES ◽  
Walter COLLI ◽  
Rosa M. de LEDERKREMER
Keyword(s):  
Fatty Acid ◽  
Trypanosoma Cruzi ◽  
Phospholipase C ◽  
Enzyme Activities ◽  
Neutral Lipids ◽  
Particulate Material ◽  
Phospholipase A1 ◽  
Free System ◽  
Lipid Moiety ◽  
A Cell

The lipid moiety in the glycosylphosphatidylinositol anchors of glycoproteins of Trypanosoma cruzi consists of an alkylacylglycerol, a lysoalkylglycerol or a ceramide. Previously, we showed that the inositolphosphoceramides (IPCs) are the major components in the precursor inositolphospholipids of epimastigote and trypomastigote forms. Using 3H-labelled subfractions of IPC, phosphatidylinositol (PI) and glycoinositolphospholipids (GIPLs) as substrates with a cell-free system, we now demonstrate the association of at least five enzyme activities with the trypanosomal membranous particulate material. These include: phospholipase A1 and phospholipase A2, enzymes that release free fatty acid from the PI and GIPLs; an acyltransferase responsible for the acylation of the generated monoacyl or monoalkylglycerolipids with endogenous unlabelled fatty acid; two activities of phospholipase C, one releasing ceramide from IPC and the other alkylacylglycerol, alkylglycerol or diacylglycerol from PI. The neutral lipids were also generated on incubation of the GIPLs. The phospholipase C activities were inhibited by p-chloromercuriphenylsulphonic acid, as reported for other PI phospholipases C. An IPC-fatty-acid hydrolase, releasing fatty acid from the labelled IPC, was also observed. The enzyme activities reported in the present study may be acting in remodelling reactions leading to the anchor of the mature glycoproteins of T. cruzi.

Regulation of Mesenchymal Progenitor Cell-Induced Neo-Vascularization by Endothelial Progenitor Cell-Derived Exosomes

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 5188-5188
Author(s):  
Thomas Lener ◽  
Doris Peckl-Schmid ◽  
Mario Gimona ◽  
Michaela Oeller ◽  
Eva Rohde
Keyword(s):  
Progenitor Cell ◽  
Conflicts Of Interest ◽  
Culture Media ◽  
Mrna Level ◽  
Cell Types ◽  
Human Umbilical Cord ◽  
Specific Marker ◽  
Endothelial Colony Forming Cells ◽  
A Cell ◽  
The Individual

Abstract Abstract 5188 Background and rationale Despite advances in the application of autologous mesenchymal stem/progenitor cells (MSPCs) and endothelial colony forming cells (ECFCs) for novel regenerative therapies, our understanding of the basic mechanisms involved in therapeutic neovascularization remains incomplete. Specifically, the individual contribution of the cell types to vessel formation and maintenance is poorly understood. Here we investigate if MSPC-derived exosomes (small vesicles that are secreted into the extracellular space and fuse with other cells to deliver mRNAs, regulatory miRNAs and proteins) can promote ECFC proliferation, migration and differentiation. Results We have generated exosome-enriched fractions from conditioned culture media of human umbilical cord or bone marrow-derived MSCPs propagated in human platelet lysate. These purified fractions were added to the culture media of ECFCs for 48 – 72 hours. Employing FACS analysis, microscopy, and the automated xCELLigence system (ROCHE) we uncovered that MSPC exosomes significantly alter the morphology and the proliferative index of ECFCs, as well as their specific marker profile. Moreover we identified that exosome enriched fractions are sufficient for modifying the expression pattern of the collagen sensor DDR1 at the mRNA level and also influence the levels of the DDR1 regulatory miRNA 199. Significantly, exosome-enriched fractions from ECFCs did not elicit any detectable alterations in ECFCs themselves, whereas we could see changes in morphology, migratory potential, proliferative activity and marker expression in MSPCs. Conclusions Taken together our data suggest that progenitor cell-derived exosomes contribute to the neo-vascularization process induced by pairwise injection of ECFCs and MSPCs, and that at least part of the role executed by MSPCs could be delivered in a cell-free manner through exosome-enriched preparations. Disclosures: No relevant conflicts of interest to declare.

Dendritic cells of the human epidermis: immuno-electron microscopic studies of la antigen reactivity

1978 ◽  
Vol 36 (2) ◽  
pp. 644-645
Author(s):  
G. Rowden ◽  
M. G. Lewis ◽  
T. M. Phillips
Keyword(s):  
Dendritic Cells ◽  
Langerhans Cells ◽  
Cell Types ◽  
Cell Type ◽  
Electron Microscopic ◽  
La Antigen ◽  
Microscopic Studies ◽  
A Cell ◽  
C3 Receptors ◽  
Antigen Reactivity

Langerhans cells of mammalian stratified squamous epithelial have proven to be an enigma since their discovery in 1868. These dendritic suprabasal cells have been considered as related to melanocytes either as effete cells, or as post divisional products. Although grafting experiments seemed to demonstrate the independence of the cell types, much confusion still exists. The presence in the epidermis of a cell type with morphological features seemingly shared by melanocytes and Langerhans cells has been especially troublesome. This so called "indeterminate", or " -dendritic cell" lacks both Langerhans cells granules and melanosomes, yet it is clearly not a keratinocyte. Suggestions have been made that it is related to either Langerhans cells or melanocyte. Recent studies have unequivocally demonstrated that Langerhans cells are independent cells with immune function. They display Fc and C3 receptors on their surface as well as la (immune region associated) antigens.

Membrane microdomains: lessons from microscopy

1995 ◽  
Vol 53 ◽  
pp. 776-777
Author(s):  
J.M. Robinson ◽  
J.M Oliver
Keyword(s):  
Spatial Distribution ◽  
Plasma Membrane ◽  
Epithelial Cells ◽  
Plasma Membranes ◽  
Cell Types ◽  
Imaging Modalities ◽  
Membrane Microdomains ◽  
Membrane Domains ◽  
Lateral Heterogeneity ◽  
Functional Importance

Specialized regions of plasma membranes displaying lateral heterogeneity are the focus of this Symposium. Specialized membrane domains are known for certain cell types such as differentiated epithelial cells where lateral heterogeneity in lipids and proteins exists between the apical and basolateral portions of the plasma membrane. Lateral heterogeneity and the presence of microdomains in membranes that are uniform in appearance have been more difficult to establish. Nonetheless a number of studies have provided evidence for membrane microdomains and indicated a functional importance for these structures.This symposium will focus on the use of various imaging modalities and related approaches to define membrane microdomains in a number of cell types. The importance of existing as well as emerging imaging technologies for use in the elucidation of membrane microdomains will be highlighted. The organization of membrane microdomains in terms of dimensions and spatial distribution is of considerable interest and will be addressed in this Symposium.

Nonspecific Chronic Back Pain: Sixth Edition Approaches

2019 ◽  
Vol 24 (5) ◽  
pp. 14-15
Author(s):  
Jay Blaisdell ◽  
James B. Talmage
Keyword(s):  
Back Pain ◽  
Chronic Back Pain ◽  
Intervertebral Disk ◽  
Key Factors ◽  
Sixth Edition ◽  
Whole Person ◽  
Class 1 ◽  
A Cell ◽  
Intervertebral Disk Herniation ◽  
The Individual

Abstract Ratings for “non-specific chronic, or chronic reoccurring, back pain” are based on the diagnosis-based impairment method whereby an impairment class, usually representing a range of impairment values within a cell of a grid, is selected by diagnosis and “specific criteria” (key factors). Within the impairment class, the default impairment value then can be modified using non-key factors or “grade modifiers” such as functional history, physical examination, and clinical studies using the net adjustment formula. The diagnosis of “nonspecific chronic, or chronic reoccurring, back pain” can be rated in class 0 and 1; the former has a default value of 0%, and the latter has a default value of 2% before any modifications. The key concept here is that the physician believes that the patient is experiencing pain, yet there are no related objective findings, most notably radiculopathy as distinguished from “nonverifiable radicular complaints.” If the individual is found not to have radiculopathy and the medical record shows that the patient has never had clinically verifiable radiculopathy, then the diagnosis of “intervertebral disk herniation and/or AOMSI [alteration of motion segment integrity] cannot be used.” If the patient is asymptomatic at maximum medical improvement, then impairment Class 0 should be chosen, not Class 1; a final whole person impairment rating of 1% indicates incorrect use of the methodology.

Role of Transcriptional Read-Through in PRE Activity in Drosophila melanogaster

Acta Naturae ◽  
2016 ◽  
Vol 8 (2) ◽  
pp. 79-86 ◽  
Author(s):  
P. V. Elizar’ev ◽  
D. V. Lomaev ◽  
D. A. Chetverina ◽  
P. G. Georgiev ◽  
M. M. Erokhin
Keyword(s):  
Dna Sequences ◽  
Cell Types ◽  
Transcription Terminator ◽  
Response Elements ◽  
Polycomb Response Elements ◽  
The Individual ◽  
Multicellular Organisms ◽  
Different Cell Types ◽  
Main Factor

Maintenance of the individual patterns of gene expression in different cell types is required for the differentiation and development of multicellular organisms. Expression of many genes is controlled by Polycomb (PcG) and Trithorax (TrxG) group proteins that act through association with chromatin. PcG/TrxG are assembled on the DNA sequences termed PREs (Polycomb Response Elements), the activity of which can be modulated and switched from repression to activation. In this study, we analyzed the influence of transcriptional read-through on PRE activity switch mediated by the yeast activator GAL4. We show that a transcription terminator inserted between the promoter and PRE doesnt prevent switching of PRE activity from repression to activation. We demonstrate that, independently of PRE orientation, high levels of transcription fail to dislodge PcG/TrxG proteins from PRE in the absence of a terminator. Thus, transcription is not the main factor required for PRE activity switch.

Polycystin expression is temporally and spatially regulated during renal development

1997 ◽  
Vol 272 (5) ◽  
pp. F602-F609 ◽  
Author(s):  
J. Van Adelsberg ◽  
S. Chamberlain ◽  
V. D'Agati
Keyword(s):  
Plasma Membranes ◽  
Predicted Amino Acid Sequence ◽  
Renal Development ◽  
Polycystic Kidney ◽  
Fetal Kidney ◽  
Spatial Regulation ◽  
Adult Kidney ◽  
A Cell ◽  
Autosomal Dominant Polycystic Kidney ◽  
Membrane Spanning

Mutations in PKD1 cause autosomal dominant polycystic kidney disease (ADPKD), a common genetic disease in which cysts form from kidney tubules. The predicted product of this gene is a novel protein with cell-adhesive and membrane-spanning domains. To test the hypothesis that polycystin, the product of the PKD1 gene, is a cell adhesion molecule, we raised antibodies against peptides derived from the unduplicated, membrane-spanning portion of the predicted amino acid sequence. These antibodies recognized membrane-associated polypeptides of 485 and 245 kDa in human fetal kidney homogenates. Expression was greater in fetal than adult kidney by both Western blot analysis and immunofluorescence. In fetal kidney, polycystin was localized to the plasma membranes of ureteric bud and comma and S-shaped bodies. However, in more mature tubules in fetal kidney, in adult kidney, and in polycystic kidney, the majority of polycystin staining was intracellular. The temporal and spatial regulation of polycystin expression during renal development lead us to speculate that polycystin may play a role in nephrogenesis.

scholarly journals Effects of exogenous lipids and cold acclimation on lycopene production and fatty acid composition in Blakeslea trispora

AMB Express ◽  
2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Feng Lingran ◽  
Wang Qiang ◽  
Yu Xiaobin ◽  
Fred Kwame
Keyword(s):  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Acid Composition ◽  
Neutral Lipids ◽  
Feedback Regulation ◽  
Total Content ◽  
Blakeslea Trispora ◽  
Plant Oils ◽  
Intracellular Lipids ◽  
Lycopene Production

Abstract Exogenous lipids serving as stimulators to improve lycopene production in Blakeslea trispora have been widely reported. However, the selection basis of exogenous lipids and their effects on intracellular lipids are not very clear. In this study, five plant oils with different fatty acid compositions were selected to investigate their effects on lycopene production, fatty acid composition and the desaturation degree of intracellular lipids. Among the oils, soybean oil, with a fatty acid composition similar to that of mycelium, exhibited the best stimulating effect on lycopene formation (improvement of 82.1%). The plant oils enhanced the total content of intracellular lipids and the desaturation degree of reserve lipids due to the alteration of fatty acid composition, especially in neutral lipids. Lycopene production was increased with the improved desaturation degree of intracellular lipids, which may be attributed to the enhancement of storage capacity for lycopene in storage lipid, thus reducing the feedback regulation of free lycopene. In addition, the increase of the desaturation degree of reserve lipids through temperature-changing fermentation also enhanced lycopene production. The present study could serve as a basis for a better understanding of the relationship between the fatty acid composition of reserve lipids and lycopene production.

scholarly journals 588 Distinct Roles of the Long-Chain Fatty Acid Receptor GPR120 in Different Cell Types of the Intestinal Epithelium

2014 ◽  
Vol 146 (5) ◽  
pp. S-110-S-111
Author(s):  
Arivarasu Natarajan Anbazhagan ◽  
Shubha Priyamvada ◽  
Tarunmeet Gujral ◽  
Waddah A. Alrefai ◽  
Pradeep K. Dudeja ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Intestinal Epithelium ◽  
Cell Types ◽  
Chain Fatty Acid ◽  
Long Chain Fatty Acid ◽  
Acid Receptor ◽  
Different Cell Types ◽  
Long Chain ◽  
Fatty Acid Receptor

Differential expression of ORCC and CFTR induced by low temperature in CF airway epithelial cells

1995 ◽  
Vol 268 (1) ◽  
pp. C243-C251 ◽  
Author(s):  
M. E. Egan ◽  
E. M. Schwiebert ◽  
W. B. Guggino
Keyword(s):  
Cystic Fibrosis ◽  
Epithelial Cells ◽  
Incubation Temperature ◽  
Cell Types ◽  
Airway Epithelial Cells ◽  
Airway Epithelial ◽  
Channel Activity ◽  
Patch Clamp Recording ◽  
Cl Channel ◽  
Channel Expression

When nonepithelial cell types expressing the delta F508-cystic fibrosis transmembrane conductance regulator (CFTR) mutation are grown at reduced temperatures, the mutant protein can be properly processed. The effect of low temperatures on Cl- channel activity in airway epithelial cells that endogenously express the delta F508-CFTR mutation has not been investigated. Therefore, we examined the effect of incubation temperature on both CFTR and outwardly rectifying Cl- channel (ORCC) activity in normal, in cystic fibrosis (CF)-affected, and in wild-type CFTR-complemented CF airway epithelia with use of a combination of inside-out and whole cell patch-clamp recording, 36Cl- efflux assays, and immunocytochemistry. We report that incubation of CF-affected airway epithelial cells at 25-27 degrees C is associated with the appearance of a protein kinase A-stimulated CFTR-like Cl- conductance. In addition to the appearance of CFTR Cl- channel activity, there is, however, a decrease in the number of active ORCC when cells are grown at 25-27 degrees C, suggesting that the decrease in incubation temperature may be associated with multiple alterations in ion channel expression and/or regulation in airway epithelial cells.

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