Ferromagnetic resonance for the quantification of superparamagnetic iron oxide nanoparticles in biological materials

The aim of the present work is the presentation of a quantification methodology for the control of the amount of superparamagnetic iron oxide nanoparticles (SPIONs) administered in biological materials by means of the ferromagnetic resonance technique (FMR) applied to studies both in vivo and in vitro. The in vivo study consisted in the analysis of the elimination and biodistribution kinetics of SPIONs after intravenous administration in Wistar rats. The results were corroborated by X-ray fluorescence. For the in vitro study, a quantitative analysis of the concentration of SPIONs bound to the specific AC133 monoclonal antibodies was carried out in order to detect the expression of the antigenic epitopes (CD133) in stem cells from human umbilical cord blood. In both studies FMR has proven to be an efficient technique for the SPIONs quantification per volume unit (in vivo) or per labeled cell (in vitro)

Gait speed, balance and functional capacity in a sample of community-dwelling older adults

Introduction: Falls in older people is an important public health concern since they are responsible for a high number of hospitalizations, health complications, disability, and death. Gait speed has been identified as a predictor of health state in elderly populations and it is related to falls and functional capacity. The aim of this study was to identify the risk of falling in a sample of Portuguese older adults living in the community and to investigate the associations between gait speed, balance, and functionality. Methods: This was a cross-sectional study. Assessment included gait speed (GS) with 4-meter walk test; balance with the Berg Balance Scale (BBS); functional capacity with the Composite Physical Function Scale (CPF). Descriptive and correlational statistics were performed to analyze data. Results: 46 community-dwelling older adults (32 women; 14 men) aged 77 ± 9 years participated in our study. Mean value for GS was 1.17 ± 0.37 m/s which is normal for this population. For BBS and CPF median was 52 and 19, respectively. BBS results revealed a risk of falling off 43% and functional capacity of our participants was at moderate levels. The study of correlations between variables also showed positive associations between GS and BBS (R = 0.631; p = 0.00) and between GS and CPF (R = 0.605; p = 0.00). Conclusions: Positive associations between GS and balance and between GS and functional capacity highlight the role of GS in the assessment of fall risk and functional capacity since it is a simple and easy test to perform.info:eu-repo/semantics/publishedVersio

Application of hyperthermia induced by superparamagnetic iron oxide nanoparticles in glioma treatment

Gliomas are a group of heterogeneous primary central nervous system (CNS) tumors arising from the glial cells. Malignant gliomas account for a majority of malignant primary CNS tumors and are associated with high morbidity and mortality. Glioblastoma is the most frequent and malignant glioma, and despite the recent advances in diagnosis and new treatment options, its prognosis remains dismal. New opportunities for the development of effective therapies for malignant gliomas are urgently needed. Magnetic hyperthermia (MHT), which consists of heat generation in the region of the tumor through the application of magnetic nanoparticles subjected to an alternating magnetic field (AMF), has shown positive results in both preclinical and clinical assays. The aim of this review is to assess the relevance of hyperthermia induced by magnetic nanoparticles in the treatment of gliomas and to note the possible variations of the technique and its implication on the effectiveness of the treatment. We performed an electronic search in the literature from January 1990 to October 2010, in various databases, and after application of the inclusion criteria we obtained a total of 15 articles. In vitro studies and studies using animal models showed that MHT was effective in the promotion of tumor cell death and reduction of tumor mass or increase in survival. Two clinical studies showed that MHT could be applied safely and with few side effects. Some studies suggested that mechanisms of cell death, such as apoptosis, necrosis, and antitumor immune response were triggered by MHT. Based on these data, we could conclude that MHT proved to be efficient in most of the experiments, and that the improvement of the nanocomposites as well as the AMF equipment might contribute toward establishing MHT as a promising tool in the treatment of malignant gliomas

A reduction in CD90 (THY-1) expression results in increased differentiation of mesenchymal stromal cells

Background: Mesenchymal stromal cells (MSCs) are multipotent progenitor cells used in several cell therapies. MSCs are characterized by the expression of CD73, CD90, and CD105 cell markers, and the absence of CD34, CD45, CD11a, CD19, and HLA-DR cell markers. CD90 is a glycoprotein present in the MSC membranes and also in adult cells and cancer stem cells. The role of CD90 in MSCs remains unknown. Here, we sought to analyse the role that CD90 plays in the characteristic properties of in vitro expanded human MSCs. Methods: We investigated the function of CD90 with regard to morphology, proliferation rate, suppression of T-cell proliferation, and osteogenic/adipogenic differentiation of MSCs by reducing the expression of this marker using CD90-target small hairpin RNA lentiviral vectors. Results: The present study shows that a reduction in CD90 expression enhances the osteogenic and adipogenic differentiation of MSCs in vitro and, unexpectedly, causes a decrease in CD44 and CD166 expression. Conclusion: Our study suggests that CD90 controls the differentiation of MSCs by acting as an obstacle in the pathway of differentiation commitment. This may be overcome in the presence of the correct differentiation stimuli, supporting the idea that CD90 level manipulation may lead to more efficient differentiation rates in vitro

Mesenchymal stem cell-like properties of CD133+ glioblastoma initiating cells

Glioblastoma is composed of dividing tumor cells, stromal cells and tumor initiating CD133+ cells. Recent reports have discussed the origin of the glioblastoma CD133+ cells and their function in the tumor microenvironment. The present work sought to investigate the multipotent and mesenchymal properties of primary highly purified human CD133+ glioblastoma-initiating cells. To accomplish this aim, we used the following approaches: i) generation of tumor subspheres of CD133+ selected cells from primary cell cultures of glioblastoma; ii) analysis of the expression of pluripotency stem cell markers and mesenchymal stem cell (MSC) markers in the CD133+ glioblastoma-initiating cells; iii) side-by-side ultrastructural characterization of the CD133+ glioblastoma cells, MSC and CD133+ hematopoietic stem cells isolated from human umbilical cord blood (UCB); iv) assessment of adipogenic differentiation of CD133+ glioblastoma cells to test their MSC-like in vitro differentiation ability; and v) use of an orthotopic glioblastoma xenograft model in the absence of immune suppression. We found that the CD133+ glioblastoma cells expressed both the pluripotency stem cell markers (Nanog, Mush-1 and SSEA-3) and MSC markers. In addition, the CD133+ cells were able to differentiate into adipocyte-like cells. Transmission electron microscopy (TEM) demonstrated that the CD133+ glioblastoma-initiating cells had ultrastructural features similar to those of undifferentiated MSCs. In addition, when administered in vivo to non-immunocompromised animals, the CD133+ cells were also able to mimic the phenotype of the original patient’s tumor. In summary, we showed that the CD133+ glioblastoma cells express molecular signatures of MSCs, neural stem cells and pluripotent stem cells, thus possibly enabling differentiation into both neural and mesodermal cell types

Characterization of Adherent Umbilical Cord Blood Stromal Cells Regarding Passage, Cell Number, and Nano-biomarking Utilization

Adherent umbilical cord blood stromal cells (AUCBSCs) are multipotent cells with differentiation capacities. Therefore, these cells have been investigated for their potential in cell-based therapies. Quantum Dots (QDs) are an alternative to organic dyes and fluorescent proteins because of their long-term photostability. In this study we determined the effects of the cell passage on AUCBSCs morphology, phenotype, and differentiation potential. QDs labeled AUCBSCs in the fourth cell passage were differentiated in the three mesodermal lineages and were evaluated using cytochemical methods and transmission electron microscopy (TEM). Gene and protein expression of the AUCBSCs immunophenotypic markers were also evaluated in the labeled cells by real-time quantitative PCR and flow cytometry. In this study we were able to define the best cellular passage to work with AUCBSCs and we also demonstrated that the use of fluorescent QDs can be an efficient nano-biotechnological tool in differentiation studies because labeled cells do not have their characteristics compromised.Instituto de Ensino e Pesquisa Albert EinsteinFundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq

The Ultrastructural Study of Tumorigenic Cells Using Nanobiomarkers

Despite recent advances, patients with malignant brain tumors still have a poor prognosis. Glioblastoma (WHO grade 4 astrocytoma), the most malignant brain tumor, represents 50% of all astrocytomas, with a median survival rate of <1 year. It is, therefore, extremely important to search for new diagnostic and therapeutic approaches for patients with glioblastoma. This study describes the application of superparamagnetic nano-particles of iron oxide, as well as monoclonal antibodies, of immunophenotypic significance, conjoined to quantum dots for the ultrastructural assessment of glioblastoma cells. for this proposal, an immunophenotypic study by flow cytometry was carried out, followed by transmission electron microscopy analysis. the process of tumor cell labeling using nanoparticles can successfully contribute to the identification of tumorigenic cells and consequently for better understanding of glioblastoma genesis and recurrence. in addition, this method may help further studies in tumor imaging, diagnosis, and prognostic markers detection.Instituto Israelita de Ensino e Pesquisa Albert EinsteinSociedade Beneficente Israelita Brasileira Hospital Albert Einstein (SBIBHAE)SBIBHAE, INCE, IIEPAE, BR-05651901 São Paulo, BrazilIIEPAE, Ctr Pesquisa Expt, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Neurol & Neurochirurg, São Paulo, BrazilUniv Fed Sao Joao Del Rei, Sao Joao Del Rei, BrazilUNESP, Dept Biol, Inst Biociencias, Rio Claro, BrazilUniv São Paulo, Dept Radiol, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Neurol & Neurochirurg, São Paulo, BrazilInstituto Israelita de Ensino e Pesquisa Albert Einstein: IIEP/278-07Web of Scienc