The in vivo distribution of 50 nm clusters of polyethylene glycol-conjugated superparamagnetic iron oxide nanoparticles (SPIONs-PEG) was conducted in this study. SPIONs-PEG were synthesized de novo, and their structure and paramagnetic behaviors were analyzed by specific methods (TEM, DLS, XRD, VSM). Wistar rats were treated with 10 mg Fe/kg body weight SPIONs-PEG and their organs and blood were examined at two intervals for short-term (15, 30, 60, 180 min) and long-term (6, 12, 24 h) exposure evaluation. Most exposed organs were investigated through light and transmission electron microscopy, and blood and urine samples were examined through fluorescence spectrophotometry. SPIONs-PEG clusters entered the bloodstream after intraperitoneal and intravenous administrations and ended up in the urine, with the highest clearance at 12 h. The skin and spleen were within normal histological parameters, while the liver, kidney, brain, and lungs showed signs of transient local anoxia or other transient pathological affections. This study shows that once internalized, the synthesized SPIONs-PEG disperse well through the bloodstream with minor to nil induced tissue damage, are biocompatible, have good clearance, and are suited for biomedical applications.

Context and objective. In this study, we aimed to investigate how moderate physical activity improves the bone ultrastructural parameters in rats with glucocorticoidinduced secondary osteoporosis. Animals and Methods. Research has been carried out on Wistar female rats. Secondary osteoporosis was induced through daily i.m.1.5 mg/kgbw methylprednisolone, over a period of 30 days. A group of rats with induced secondary osteoporosis were subjected to physical activity (swimming) for one hour/day for 30 days. Rats were sacrificed 24 hours after the last administration and femoral bones were used for electron microscopy analysis. Results. The ultrastructural findings obtained from the rats with osteoporosis showed varying degrees of alteration in all cellular components. A moderate physical effort led to the overall maintenance of the normal ultrastructure of the cells and connective components, protecting the lamellar structure of the compact bone from the deleterious effects of glucocorticoid. The shape and components of osteocytes were also preserved and the accumulation of lipids in the bone marrow diminished. Conclusions. Physical exercise has been shown to have a protective role by lowering the development of structural alterations specific to osteoporosis. Therefore, moderate physical exercises are recommended for improving the structure of the bone mass affected by glucocorticoid treatment.

Dumontinia tuberosa fungus was observed in different stages of development growing on the roots of Ranunculus ficaria in Cluj-Napoca (Romania), over the course of several years. It is not frequently encountered, therefore, we decided that will be interesting to cultivate it on nutritive medium, and to use the morphological data and the colony’s characteristics to identify the fungus. The identity of the fungus was reaffirmed through a molecular analysis of sclerotium DNA sequences. A new favourable nutritive medium for the growth and development of the fungus is proposed. The morphology and ultrastructure of the fungus were examined by light and electron microscopy, and micrographs of the relevant details are provided. Differences between the ultrastructural characteristics of sclerotium, apothecium stipe, ascospores, asci and paraphyses are presented and discussed. Intercellular spaces were identified in sclerotium and apothecium stipe and the paraphyses. Asci and ascospores were found to be covered by a sticky mucilage. The ultrastructural characteristics of the aforementioned tissues are presented for different developmental stages. Additionally, the main food stores of the fungus, represented by glycogen, lipids and proteins, are located and described along with other characteristic compounds, such as melanin pigment and a glucan extracellular matrix. The present study complements prior information on the worldwide distribution of this rare species in nature and contributes new findings regarding its morphological and ultrastructural characteristics.