Biomedical subjects

Maria Rosaria Bianco

Publications and source records attributed to Maria Rosaria Bianco.

4 recordsLinked to original sources

PubMed2006

Genetically modified pigs produced with a nonviral episomal vector.

Genetic modification of cells and animals is an invaluable tool for biotechnology and biomedicine. Currently, integrating vectors are used for this purpose. These vectors, however, may lead to insertional mutagenesis and variable transgene expression and can undergo silencing. Scaffold/matrix attachment region-based vectors are nonviral expression systems that replicate autonomously in mammalian cells, thereby making possible safe and reliable genetic modification of higher eukaryotic cells and organisms. In this study, genetically modified pig fetuses were produced with the scaffold/matrix attachment region-based vector pEPI, delivered to embryos by the sperm-mediated gene transfer method. The pEPI vector was detected in 12 of 18 fetuses in the different tissues analyzed and was shown to be retained as an episome. The reporter gene encoded by the pEPI vector was expressed in 9 of 12 genetically modified fetuses. In positive animals, all tissues analyzed expressed the reporter gene; moreover in these tissues, the positive cells were on the average 79%. The high percentage of EGFP-expressing cells and the absence of mosaicism have important implications for biotechnological and biomedical applications. These results are an important step forward in animal transgenesis and can provide the basis for the future development of germ-line gene therapy.

Animals↗

PubMed2005

Multi-transgenic pigs expressing three fluorescent proteins produced with high efficiency by sperm mediated gene transfer.

Multi-gene transgenic pigs would be of benefit for large animal models in medical, agricultural, and pharmaceutical applications; in particular for xenotransplantation, where extensive genetic manipulation of donor pigs is required to make them suitable for organ grafting to humans. We used the sperm mediated gene transfer (SMGT) method to produce with high efficiency multi-gene transgenic pigs using three genes coding for fluorescent proteins: enhanced blue (EBFP), green (EGFP), and red (DsRed2). All three fluorescent proteins were expressed in 171 out of 195 normally developed morula/blastocysts examined at day 6 post insemination (88%). Genomic DNA of 18 piglets born from two litters was screened by PCR, showing that all piglets were transgenic with at least one gene, 7/18 piglets were triple transgenic, 7/18 double transgenic, and 4/18 single transgenic. Fluorescence in situ hybridization (FISH) analysis revealed multiple sites of integration of the transgenes. RNA and protein expression was found in muscle, heart, liver, hair, and peripheral blood mononuclear cells (PBMCs). These results show that SMGT is an effective method for introducing multiple genes into pigs as shown by the simultaneous expression of three fluorescent proteins.

Animals↗

PubMed2003

Fibrillogenesis and cytotoxic activity of the amyloid-forming apomyoglobin mutant W7FW14F.

The apomyoglobin mutant W7FW14F forms amyloid-like fibrils at physiological pH. We examined the kinetics of fibrillogenesis using three techniques: the time dependence of the fluorescence emission of thioflavin T and 1-anilino-8-naphthalenesulfonate, circular dichroism measurements, and electron microscopy. We found that in the early stage of fibril formation, non-native apomyoglobin molecules containing beta-structure elements aggregate to form a nucleus. Subsequently, more molecules aggregate around the nucleus, thereby resulting in fibril elongation. We evaluated by MTT assay (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) the cytotoxicity of these aggregates at the early stage of fibril elongation versus mature fibrils and the wild-type protein. Similar to other amyloid-forming proteins, cell toxicity was not due to insoluble mature fibrils but rather to early pre-fibrillar aggregates. Propidium iodide uptake showed that cell toxicity is the result of altered membrane permeability. Phalloidin staining showed that membrane damage is not associated to an altered cell shape caused by changes in the cytoskeleton.

Anilino Naphthalenesulfonates↗

PubMedDate not supplied

[Case report: RAEB in a patient with rheumatoid arthritis treated with methotrexate and infliximab].

Anti TNF-alpha drugs seem to be the new frontier of Rheumatoid Arthritis (RA) therapy. The association infliximab methotrexate has been approved for the treatment of RA not responding to the classic therapy, but the short clinical experience in using antiTNF-alpha molecules brings to segnalation of new risks or adverse events. We describe a case of a patient, treated for many years with classic RA therapy, which developed a refractory anemia after treatment with association infliximab-methotrexate.

Anemia, Refractory, with Excess of Blasts↗