Comparative genomic hybridization and amplotyping by arbitrarily primed PCR in stage A B-CLL

Cytogenetic analysis is useful in the diagnosis and to assess prognosis of B-cell chronic lymphocytic leukemia (B-CLL). However, successful cytogenetics by standard techniques has been hindered by the low in vitro mitotic activity of the malignant B-cell population. Fluorescence in situ hybridization (FISH) has become a useful tool, but it does not provide an overall view of the aberrations. To overcome this hurdle, two DNA-based techniques have been tested in the present study: comparative genomic hybridization (CGH) and amplotyping by arbitrarily primed PCR (AP-PCR). Comparative genomic hybridization resolution depends upon the 400-bands of the human standard karyotype. AP-PCR allows detection of allelic losses and gains in tumor cells by PCR fingerprinting, thus its resolution is at the molecular level. Both techniques were performed in 23 patients with stage A B-CLL at diagnosis. The results were compared with FISH. The sensitivity of AP-PCR was greater than CGH (62% vs. 43%). The use of CGH combined with AP-PCR allowed to detect genetic abnormalities in 79% (15/19) of patients in whom G-banding was not informative, providing a global view of the aberrations in a sole experiment. This study shows that combining these two methods with FISH, makes possible a more precise genetic characterization of patients with B-CLL

Extracellular vesicles from the microalga Tetraselmis chuii are biocompatible and exhibit unique bone tropism along with antioxidant and anti-inflammatory properties

Extracellular vesicles (EVs) are membrane-enclosed bio-nanoparticles secreted by cells and naturally evolved to transport various bioactive molecules between cells and even organisms. These cellular objects are considered one of the most promising bio-nanovehicles for the delivery of native and exogenous molecular cargo. However, many challenges with state-of-the-art EV-based candidates as drug carriers still exist, including issues with scalability, batch-to-batch reproducibility, and cost-sustainability of the final therapeutic formulation. Microalgal extracellular vesicles, which we named nanoalgosomes, are naturally released by various microalgal species. Here, we evaluate the innate biological properties of nanoalgosomes derived from cultures of the marine microalgae Tetraselmis chuii, using an optimized manufacturing protocol. Our investigation of nanoalgosome biocompatibility in preclinical models includes toxicological analyses, using the invertebrate model organism Caenorhabditis elegans, hematological and immunological evaluations ex vivo and in mice. We evaluate nanoalgosome cellular uptake mechanisms in C. elegans at cellular and subcellular levels, and study their biodistribution in mice with accurate space-time resolution. Further examination highlights the antioxidant and anti-inflammatory bioactivities of nanoalgosomes. This holistic approach to nanoalgosome functional characterization demonstrates that they are biocompatible and innate bioactive effectors with unique bone tropism. These findings suggest that nanoalgosomes have significant potential for future therapeutic applications

Effect of aging on silica aerogel properties

Silica aerogels’ unique physical and chemical properties make them fascinating materials for a wide variety of applications. In addition to hydrophobization by silylation, aging is very important in the synthesis of silica aerogel by ambient pressure drying. Here we systematically study the effect of aging on the physico-chemical properties of silica aerogel with emphasis on ambient dried materials. Silica gels were aged for different times and at different temperatures in their gelation liquid (without solvent exchange), hydrophobized in hexamethyldisiloxane and subsequently dried either at ambient pressure or from supercritical CO2. Dynamic oscillatory rheological measurements demonstrate that aging reinforces the alcogels, particularly at high strain. The specific surface area decreases with increasing aging time and temperature as a consequence of Ostwald ripening processes during aging. With increasing aging time and temperature, the linear shrinkage and bulk density decrease and the pore size and pore volume increase for the ambient dried gels, but remain nearly constant for supercritically dried gels. Small-Angle X-ray scattering does not detect significant structural changes at length scales smaller than about hundred nanometers, but hints at systematic variations at larger length scales. The findings of this study highlight the importance of aging to increase the ability of the gel particle network to withstand irreversible pore collapse during ambient pressure drying

Comparison between iMSD and 2D-pCF analysis for molecular motion studies on in vivo cells: The case of the epidermal growth factor receptor

Image correlation analysis has evolved to become a valuable method of analysis of the diffusional motion of molecules in every points of a live cell. Here we compare the iMSD and the 2D-pCF approaches that provide complementary information. The iMSD method provides the law of diffusion and it requires spatial averaging over a small region of the cell. The 2D-pCF does not require spatial averaging and it gives information about obstacles for diffusion at pixel resolution. We show the analysis of the same set of data by the two methods to emphasize that both methods could be needed to have a comprehensive understanding of the molecular diffusional flow in a live cell