The behavior of vascular endothelial cells (EC) is an important factor in the processes involved in angiogenesis, but the regulatory mechanisms of angiogenesis, especially underlying the tubulogenesis by EC are not yet clear. Although a number of in vitro experimental models of tubulogenesis have been developed by use of cultured EC, most of those models are too complex to be easily handled and further, the culture media are usually supplemented with serum, creating problems in interpretation of experimental results. To generate a simple in vitro angiogenesis study model under serum-free culture conditions, we adapted a murine microvascular endothelial cell line, F-2, to a chemically defined medium, Cos Medium 001, and successfully established a subline of F-2, designated F-2C, which revealed a unique growth pattern. In Cos Medium 001, F-2C proliferates in a cobblestone pattern at an early growth stage, but, at a late growth stage, spontaneously differentiates to form three-dimensional honeycomblike tubular structures without the supplementation of any specific factors. The cell aggregation activity of F-2C in the presence of Ca2+ was much greater than that of F-2. The amount of subendothelial matrix deposited by F-2C was significantly higher than that by F-2, and increased prominently after the F-2C cells reached the differentiating stage of tubulogenesis. These findings indicate that F-2C is a new EC line in which tubulogenesis is spontaneously induced by the marked deposition of basement membrane analog to the subendothelial matrix and by the enhancement of presumable cadherin activity. We suggest that this cell line, F-2C, represents a simple and useful in vitro angiogenesis model.

Animals↗

PubMedDate not supplied

Immunoelectron microscopy and immunofluorescence antigenic mapping: diagnostic applications.

In selected situations, direct and indirect IEM may provide important diagnostic information for the clinician, as pertains to the diagnosis and therefore prognosis in a given patient. As discussed, however, all of the more conventional approaches should be pursued before consideration is given to the performance of IEM, knowing its relative cost and technical difficulty. In contrast, we consider immunofluorescence antigenic mapping to be the diagnostic method of choice for the determination of the type of inherited EB present in affected individuals. When additional ultrastructural or morphometric data is required, then TEM can be performed as an adjunct study once it is determined by mapping technique that additional useful information may be derived.

Antigens↗

PubMedDate not supplied

Effects of adrenaline and isoprenaline on hepatic venous haemodynamics and venous return in the dog.

1. The effects of adrenoceptor agonists on venous haemodynamics were examined, utilizing the lower half perfusion method in dogs. 2. Femoral arterial pressure, central venous pressure, thoracic vena caval flow, abdominal vena caval flow, renal venous flow and femoral venous flow were measured simultaneously usning electronic transducers and electromagnetic flow-meters. Hepatic volume change was monitored by the strain-guage arch. 3. Single injections of both adrenaline (1.0 microgram/kg) and isoprenaline (1.0 microgram/kg) intra-aortically produced an increase in venous return, adrenaline transiently and isoprenaline continuously. 4. Epinephrine increased hepatic venous flow, while isoprenaline increased only abdominal vena caval flow. 5. These findings suggest that effects of alpha-adrenoceptors are more pronounced on the hepatic vein, while on other peripheral veins, effects of beta-adrenoceptors are more pronounced.

Animals↗

PubMedDate not supplied

Validation of the mouse peripheral blood micronucleus assay using acridine orange supravital staining with urethane.

The mouse peripheral blood micronucleus assay using acridine orange supravital staining was compared with the standard bone marrow assay using urethane (ethyl carbamate)-treated mice. Urethane was intraperitoneally injected to CD-1 and BDF1 mice at doses ranging from 62 to 1000 and 62 to 250 mg/kg, respectively. Peripheral blood was collected from the tail 0, 24, 48, and 72 h and bone marrow cells were smeared at 24 and 42 h after the treatment. Although the response of micronucleus induction in peripheral reticulocytes was delayed by about 24 h compared to that in bone marrow polychromatic erythrocytes, the maximum frequencies of micronucleated young erythrocytes were comparable. Therefore, the peripheral blood micronucleus assay using the acridine orange supravital staining method may provide a good alternative to the conventional bone marrow assay.

Acridine Orange↗

PubMedDate not supplied

Clinical features of familial hypercholesterolemia.

The clinical consequences of familial hypercholesterolemia (FH) result from its metabolic peculiarities that persist from very early childhood, leading to the accumulation of cholesterol in the form of xanthomas in skin and tendons and atheromatous lesions in the arterial wall, in particular, in the aorta and the stem of coronary arteries. Plasma cholesterol concentration markedly increases during the suckling period, soon attaining a level near 1000 mg/dl in homozygotes and 200 to 400 mg/dl in heterozygotes. By age 50, about 80% of FH males suffer from ischemic heart diseases, while only 20% to 30% of the females are moderately affected by coronary atherosclerosis. In addition to the low density lipoprotein (LDL) cholesterol level, higher triglyceride and lower high density lipoprotein (HDL) cholesterol levels correlate with an increased risk of ischemic heart diseases. A very important problem is that most of these patients do not feel themselves to be seriously ill until a severe myocardial infarction (often leading to sudden death) takes place during the third to fifth decades of life. Among the different types of receptor mutations, the incidence of ischemic heart diseases was much higher and more extensive among patients with the receptor-negative type than among those with the receptor-defective type with a residual receptor activity.

Age Factors↗