133 research outputs found
Protein sizing with Differential Dynamic Microscopy
Introduced more than fifty years ago, dynamic light scattering is routinely
used to determine the size distribution of colloidal suspensions, as well as of
macromolecules in solution, such as proteins, nucleic acids, and their
complexes. More recently, differential dynamic microscopy has been proposed as
a way to perform dynamic light scattering experiments with a microscope, with
much less stringent constraints in terms of cleanliness of the optical
surfaces, but a potentially lower sensitivity due to the use of camera-based
detectors. In this work, we push bright-field differential dynamic microscopy
beyond known limits and show it to be sufficiently sensitive to size small
macromolecules in diluted solutions. By considering solutions of three
different proteins (Bovine Serum Albumin, Lysozyme, and Pepsin), we accurately
determine the diffusion coefficient and hydrodynamic radius of both single
proteins and small protein aggregates down to concentrations of a few
milligrams per milliliter. In addition, we present preliminary results showing
unexplored potential for the determination of virial coefficients. Our results
are in excellent agreement with the ones obtained in parallel with a
state-of-the-art commercial dynamic light scattering setup, showing that
differential dynamic microscopy represents a valuable alternative for rapid,
label-free protein sizing with an optical microscope
Foreign children with cancer in Italy
<p>Abstract</p> <p>Background</p> <p>There has been a noticeable annual increase in the number of children coming to Italy for medical treatment, just like it has happened in the rest of the European Union. In Italy, the assistance to children suffering from cancer is assured by the current network of 54 centres members of the Italian Association of Paediatric Haematology and Oncology (AIEOP), which has kept records of all demographic and clinical data in the database of Mod.1.01 Registry since 1989.</p> <p>Methods</p> <p>We used the information stored in the already mentioned database to assess the impact of immigration of foreign children with cancer on centres' activity, with the scope of drawing a map of the assistance to these cases.</p> <p>Results</p> <p>Out of 14,738 cases recorded by all centres in the period from 1999 to 2008, 92.2% were born and resident in Italy, 4.1% (608) were born abroad and living abroad and 3.7% (538) were born abroad and living in Italy. Foreign children cases have increased over the years from 2.5% in 1999 to. 8.1% in 2008.</p> <p>Most immigrant children came from Europe (65.7%), whereas patients who came from America, Asia and Oceania amounted to 13.2%, 10.1%, 0.2%, respectively. The immigrant survival rate was lower compared to that of children who were born in Italy. This is especially true for acute lymphoblastic leukaemia patients entered an AIEOP protocol, who showed a 10-years survival rate of 71.0% vs. 80.7% (p < 0.001) for immigrants and patients born in Italy, respectively.</p> <p>Conclusions</p> <p>Children and adolescents are an increasingly important part of the immigration phenomenon, which occurs in many parts of the world. In Italy the vast majority of children affected by malignancies are treated in AIEOP centres. Since immigrant children are predominantly treated in northern Italy, these centres have developed a special expertise in treating immigrant patients, which is certainly very useful for the entire AIEOP network.</p
- …