Biodistribution of 125I-labeled polymeric vaccine carriers after subcutaneous injection

Polymeric nanoparticles (NPs) comprised of hydrophilic poly(γ-glutamic acid) in the main chain and hydrophobic phenylalanine in the side chain (γ-PGA-Phe) are a promising vaccine carrier for various kinds of diseases. However, little is known about the fate of subcutaneously administered γ-PGA-Phe NPs. Therefore, we newly synthesized γ-PGA graft phenylalanine and tyrosine conjugates (γ-PGA-Phe-Tyr), and then γ-PGA-Phe-Tyr NPs were labeled with ¹²⁵I for monitoring their biodistribution (γ-PGA-Phe-Tyr(¹²⁵I) NPs). Dynamic light scattering (DLS) measurements showed that γ-PGA-Phe-Tyr(¹²⁵I) NPs showed 200 nm in diameter and a negative ζ-potential, which was comparable to those of their precursors. γ-scintigraphic images showed that in mice, subcutaneously injected γ-PGA-Phe-Tyr(¹²⁵I) NPs were mainly observed at the site of injection (SOI), but not other organs 1 h after administration. However, γ-PGA-PheTyr(¹²⁵I) NPs were almost undetectable at the SOI and other organs at 11 days postinjection. Similar results were observed when γ-PGA-Phe-Tyr(¹²⁵I) NPs were subcutaneously injected into rats. Furthermore, at 11 days postinjection, 73 ± 3% of the injected dose of γ-PGA-Phe-Tyr(¹²⁵I) NPs was detected in the feces (14 ± 1%) and urine (59 ± 1%). These results clearly showed that subcutaneously injected γ-PGA-Phe-Tyr(¹²⁵I) NPs were cleared from the body, and γ-PGA-Phe NPs were safe and effective vaccine carriers.     

Differentiation of multipotent stem cells to insulin-producing cells for treatment of diabetes mellitus: bone marrow- and adipose tissue-derived cells comparison

Molecular Biology Reports - Mesenchymal stem cells (MSCs) from human adipose tissue and bone marrow have a great potential for use in cell therapy due to their ease of isolation, expansion, and...     

ASTHMA AND CARDIAC DYSPNEA—A DIFFERENTIAL DIAGNOSIS

There appear to be no infallible guides by which to differentiate between cardiac insufficiency and asthma as a cause of dyspnea, wheezing and coughing in elderly patients. Many of the symptoms of one condition are also symptoms of the other. Even the results of therapeutic trial cannot be relied upon to establish diagnosis, for drugs effective in treatment of heart disease may also help relieve asthma, and vice versa.Although there is no single factor that can be considered pathognomonic, there are certain symptoms and results of tests which are more strongly indicative of one condition than of the other. Careful evaluation of all factors, while it may not serve to establish unequivocal diagnosis, will provide a basis for judicious treatment of the patient.     

Catecholamine secretion by isolated adrenal cells.

Isolated adrenal cells were prepared by collagenase digestion of guinea pig adrenal glands. Acetylcholine stimulates the secretion of catecholamines by these isolated adrenal cells. Acetylcholine-stimulated catecholamine secretion is inhibited by cholinergic blocking agents (atropine and hexamethonium) and by local anaesthetics (tetracaine), and is dependent upon the concentration of Ca2+ in the incubation medium. In the presence of Ca2+, catecholamine secretion is also stimulated by two divalent cation ionophores, A23187 and X-537A. Cyclic nucleotides and 5'-nucleotides cause a small, non-specific stimulation of catecholamine secretion. These results indicate that isolated adrenal cells are a useful system in which to study catecholamine secretion, and support the hypothesis that increased Ca2+ entry into chromaffin cells is a sufficient stimulus for catecholamine secretion.     

The Role of Host Phylogeny Varies in Shaping Microbial Diversity in the Hindguts of Lower Termites

The hindguts of lower termites and Cryptocercus cockroaches are home to a distinct community of archaea, bacteria, and protists (primarily parabasalids and some oxymonads). Within a host species, the composition of these hindgut communities appears relatively stable, but the evolutionary and ecological factors structuring community composition and stability are poorly understood, as are differential impacts of these factors on protists, bacteria, and archaea. We analyzed the microbial composition of parabasalids and bacteria in the hindguts of Cryptocercus punctulatus and 23 species spanning 4 families of lower termites by pyrosequencing variable regions of the small-subunit rRNA gene. Especially for the parabasalids, these data revealed undiscovered taxa and provided a phylogenetic basis for a more accurate understanding of diversity, diversification, and community composition. The composition of the parabasalid communities was found to be strongly structured by the phylogeny of their hosts, indicating the importance of historical effects, although exceptions were also identified. Particularly, spirotrichonymphids and trichonymphids likely were transferred between host lineages. In contrast, host phylogeny was not sufficient to explain the majority of bacterial community composition, but the compositions of the Bacteroidetes, Elusimicrobia, Tenericutes, Spirochaetes, and Synergistes were structured by host phylogeny perhaps due to their symbiotic associations with protists. All together, historical effects probably resulting from vertical inheritance have had a prominent role in structuring the hindgut communities, especially of the parabasalids, but dispersal and environmental acquisition have played a larger role in community composition than previously expected.     

Permeant anions are not required for norepinephrine secretion from pheochromocytoma cells

The ‘chemiosmotic’ model for secretion proposed by Pollard and his colleagues (Int. Rev. Cytol. 58, 159–197, 1979) was tested with pheochromocytoma cells. Contrary to the prediction of this model, norepinephrine secretion did not require the presence of a permeant anion in the medium. Secretion was not blocked by replacing much of the Cl^? of the medium with isethionate or by replacing all of the Cl^? salts of the medium with isotonic sucrose. Biochemical evidence is presented to indicate that the cells secreted by the normal exocytotic mechanism in the sucrose medium. Making the normal bathing medium hypertonic with 300 mM sucrose increased the basal level of norepinephrine release, but alos suppressed secretion in response to a strong secretagogue (1 mM Ba²⁺). The data indicate that the Pollard model does not apply to pheochromocytoma cells, but suggest the possible involvement of osmotic pressure in exocytosis.