In vitro degranulation of rat mast cells was studied at different intervals ranging from 10 to 60 sec after adding the histamine liberator, compound 48/80 (0.4 microg/ml, 17 degrees C). The ultrastructural changes were followed by electron microscopy, and parallel assays were made to determine the histamine released. In addition, the extracellular tracers lanthanum and hemoglobin (demonstrated ...

Both routine electron microscopy and immunocytochemistry with protein A-gold were used to identify the cell types within the islet organs of four species of teleosts (Osteoglossum bicirrhosum, Pantodon buchholzi, Notopterus chitala, and Gnathonemus petersii) within Osteoglossomorpha, a subdivision with an ancient lineage. Four primary endocrine cell types, A, B, D, and F, were identified within...

In this study, we investigated the effect of different multivalent cations on granule formation. Previous experiments showed that formation of matrix EPS and their structure depend of the presence of divalent cations. This study indicates that trivalent cations are also playing an important role. However, the more compact granules were formed in the presence of all cations. The authors tried al...

A study was made of the effect of the administration of reserpine and parachlorophenylalanine, an inhibitor of 5-hydroxytryptamine (serotonin; 5-HT), on the capacity of thyroid parafollicular cells to synthesize and store 5-HT. The two drugs were given to nonhibernating bats in doses which produced an equivalent degree of depletion of 5-HT from the thyroid. Tritiated 5-hydroxytryptophan, the pr...

The outer membrane complex of Paramecium was investigated by ultrathin-sectioning techniques and by freeze-etching of unfixed cells without cryoprotectants. Granules were found in the freeze-etched cortical membrane complex in a highly ordered arrangement; morphometric analyses and partial disruption of this membrane complex showed that some of these granular membrane specializations (which we ...

Preventing polyspermy during animal fertilization relies on modifications to the egg's extracellular matrix. On fertilization in sea urchins, the contents of cortical granules are secreted and rapidly assemble into the egg's extracellular vitelline layer, forming the fertilization envelope, a proteinaceous structure that protects the zygote from subsequent sperm. Here, we document rendezvin, a ...

Developing optically transparent magnets at room temperature is an important challenge. They would bring many innovations to various industries, not only for electronic and magnetic devices but also for optical applications. Here we introduce FeCo-(Al-fluoride) nanogranular films exhibiting ferromagnetic properties with high optical transparency in the visible light region. These films have a n...

The granules of effector cytotoxic CD8 cells and natural killer (NK) cells contain a family of serine proteases called granzymes (granule-secreted enzymes) [5]. Granzymes are stored in the cytotoxic granules and require perforin to be delivered into the target cells to exert their cytotoxic function [5, 6]. Granzymes can also be released to the extracellular space and cleave extracellular matri...

The objective of the present study was to design an oral controlled drug delivery system for sparingly soluble diclofenac sodium (DCL) using guar gum as triple-layer matrix tablets. Matrix tablet granules containing 30% (D1), 40% (D2) or 50% (D3) of guar gum were prepared by the conventional wet granulation technique. Matrix tablets of diclofenac sodium were prepared by compressing three layers...

The granules of effector cytotoxic CD8 cells and natural killer (NK) cells contain a family of serine proteases called granzymes (granule-secreted enzymes) [5]. Granzymes are stored in the cytotoxic granules and require perforin to be delivered into the target cells to exert their cytotoxic function [5, 6]. Granzymes can also be released to the extracellular space and cleave extracellular matri...