Gallotannin, consisting mainly of low molecular weight esters such as penta- and hexagalloylglucoses (commercially available tannic acid produced from Turkish nutgall), can be used for increasing diversifying tissue contrast in electron microscopy. When applied on specimens previously fixed by conventional methods (aldehydes OsO4), the galloylglucoses (LMGG) penetrate satisfactorily cells induce general high with fine delineation extra- intracellular structures, especially membranes. In some...

Two heme-peptides (HP) of about 20-A diameter (heme-undecapeptide [H11P], mol wt approximately 1900 and heme-octapeptide [H8P], 1550), obtained by enzymic hydrolysis cytochrome c, were sued as probe molecules in muscle capillaries (rat diaphragm). They localized situ a perixidase reaction, enhanced the addition imidazole to incubation medium. Chromatography plasma samples showed that HPs circulate predominantly monomers for duration experiments are bound aldehyde fixatives proteins extent...

Small vascular units consisting of an arteriole, its capillaries, and the emerging venule (ACV units) were identified in rat omentum mesentery. They fixed situ processed for electron microscopy either as whole or dissected segments. Systematic examination latter (in thin sections, well freeze-cleaved preparations) showed that intercellular junctions endothelium vary characteristically from one segment to another microvasculature. In arterioles, has continuous elaborate tight with...

The interaction of homologous and heterologous albumin-gold complex (Alb-Au) with capillary endothelium was investigated in the mouse lung, heart, diaphragm. Perfusion tracer situ for from 3 to 35 min followed by washing phosphate-buffered saline, fixation perfusion, processing electron microscopy. From earliest time examined, one sometimes two rows densely packed particles bound some restricted plasma membrane microdomains that appeared as uncoated pits, plasmalemmal vesicles open on...

We investigated the interaction and transport of low-density lipoprotein (LDL) through arterial endothelium in rat aorta coronary artery, by perfusing situ native, untagged human, LDL. The latter was rendered electron-opaque after it interacted with endothelial cell subsequently fixed within tissue. achieved LDL electron-opacity an improved fixation procedure using 3,3'-diaminobenzidine, mordanting tannic acid. unequivocal identification implemented reacting immunocytochemically perfused...

A systematic survey of endothelial junctions in elastic (aorta) and muscular (mesenteric) arteries medium (renal mesenteric) large (cava inferior) size veins has been carried out the rat using freeze-cleaved preparations. The arterial endothelium is provided with a complex occluding communicating (gap junctions) comparable to, though less elaborate than, that described arterioles. particles behave like "single unit" have tendency to remain on B faces upon membrane cleavage. In venous take...

Cationized ferritin (CF), introduced systemically in vivo or by perfusion situ, binds preferentially to certain microdomains of the luminal plasmalemma fenestrated capillaries (mouse pancreas and jejunum). The density affinity binding decrease following order: fenestral diaphragms greater than coated pits proper. CF neither membrane plasmalemmal vesicles transendothelial channels nor corresponding stomatal diaphragms. distribution pattern is same when glutaraldehyde fixation precedes...

Our recent data indicate that the MHC class I-related receptor, FcRn, plays a role in regulating serum IgG levels, addition to its known transferring from mother young. In current study, distribution of FcRn adult mice has been investigated using several approaches. First, tissue anti-FcRn F(ab')2, murine IgG1 and recombinant, IgG1-derived Fc-hinge fragments analyzed, these binding proteins localize predominantly skin muscle with lesser amounts liver adipose tissue. Second, histochemical...

To investigate the chemical nature of cationic ferritin (CF)-binding sites differentiated microdomains capillary endothelium, vasculature mouse pancreas and intestinal mucosa was perfused in situ with neuraminidase, hyaluronidase, chondroitinase ABC, heparinase, three proteases: trypsin, papain, pronase. Proteases broad specificity removed all anionic sites, suggesting that latter are contributed by acid glycoproteins or proteoglycans. Neuraminidase, ABC reduced density CF-binding on...

Interstitial cells of heart atrioventricular and sigmoid valves were examined in several laboratory animals (rabbit, hamster, rat, mouse) humans. These constitute a large fraction the total cell population valve; mouse valves, they amount to approximately 30% volumetric density. By their ultrastructural features functional properties, valvular interstitial are intermediate between fibroblasts vascular smooth muscle cells. Like fibroblasts, lack basal lamina establishing direct extensive...

We have previously established that approximately 30% of the endothelial junctions in pericytic venules mouse diaphragm are open to a gap 30--60 A, and fully permeated by hemeundecapeptide (H11P) (mol diam 20 A). To estimate size limit for molecules can permeate these junctions, we administered graded tracers intravenously studied their behavior at level bipolar microvascular fields (BMFs) diaphragm. Horseradish peroxidase (HRP) 50 A) only 50% venular endothelium. Outflow through appeared be...

Lectins conjugated with either peroxidase or ferritin were used to detect specific monosaccharide residues on the luminal front of he fenestrated endothelium in capillaries murine pancreas and intestinal mucosa. The lectins tested recognize, if accessible, following residues: alpha-N-acetylgalactosaminyl (soybean lectin), beta-D-galactosyl (peanut agglutinin [PA] Ricinus communis agglutinin-120 [RCA]), beta-N-acetylglucosaminyl sialyl (wheat germ [WGA]), alpha-L-fucosyl (lotus tetragonolobus...

Objective— Oxidative stress mediated by Nox1- and Nox4-based NADPH oxidase (Nox) plays a key role in vascular diseases. The molecular mechanisms involved the regulation of Nox are not entirely elucidated. Because JAK/STAT regulates many genes linked to inflammation, cell proliferation, differentiation, we questioned whether this pathway is Nox1 Nox4 human aortic smooth muscle cells (SMCs). Methods Results— Cultured SMCs were exposed interferon γ (IFNγ) for 24 hours. Using lucigenin-enhanced...

Stem cell-based therapy for myocardial regeneration has reported several functional improvements that are attributed mostly to the paracrine effects stimulating angiogenesis and cell survival. This study was conducted comparatively evaluate potential of factors secreted by mesenchymal stem cells (MSCs) in normoxic hypoxic conditions promote tissue repair sustaining endothelial (EC) adhesion proliferation conferring protection against apoptosis. To this aim, a conditioned medium (CM)...

Histamine covalently bound to glutaraldehyde-activated ferritin was prepared as either monomers or small aggregates of approximately 0.05 0.15 micrometer Diam, suitable for electron microscopic detection histamine cellular binding sites. The histamine-ferritin conjugates (MF) maintain the capability induce opening endothelial junctions in venules. To investigate distribution receptors vascular endothelium, MF were perfused situ (mice), and various beds, particularly that diaphragm, fixed...

Small non-coding microRNAs (miRNAs) are implicated in gene regulation, including those involved coronary artery disease (CAD). Our aim was to identify whether specific serum miRNAs present the circulating lipoproteins (Lp) associated with stable or vulnerable CAD patients. A cardiovascular disease-focused screening array used assess distribution sera collected from 95 patients: 30 angina (SA), 39 unstable (UA), 26 at one month after myocardial infarction (MI) and 16 healthy control subjects....

Abstract Mesenchymal stromal cells (MSC) are attractive tools for cell-based therapy, yet the mechanisms underlying their migration and survival post-transplantation unclear. Accumulating evidence indicates that MSC apoptosis modulates both innate adaptive immune responses which impact on therapeutic effects. Using a dual tracking system, namely Luciferase expression VivoTrack680 labelling, in vivo optical imaging, we investigated of transplanted by various routes (intravenous, subcutaneous,...