The Master in International Health of Parma University: a possible model of sanitary cooperation with developing Countries

The Master in “International Health and Medicine for Cooperation with Developing Countries” was established by CUCI, based on the evaluation that many health facilities and hospitals in the low-middle income Countries are not properly equipped to face daily emergencies. The objective of the Master’s program is to train doctors with multi-sector skills, necessary to operate in healthcare ambulatories, hospitals and medical districts, characterized by poor infrastructures and management systems, that are typical in areas of high-poverty, facing cases of emergencies of various entities. The Italian Ministry of Foreign Affairs and International Cooperation is funding a number of scholarships for the best candidates classified in the final selection rating and residing in African Countries. The Course is also open to Italians who wish to extend their professional skills in order to work in resource-constrained settings. The Master course lasts one year and includes lectures, seminars, videoconferencing and internships both at the University Hospital of Parma and in other Structures / Laboratories. The final work includes a scientific section and a project work for future collaboration with the Countries from which the doctors come from. Besides the various fields of medicine, other important themes are addressed in the course, like guidelines for hospital managements, health cooperation, development, prevention strategies. Why this Master could be a model of sanitary cooperation? The WHO and the Geneva Foundation for Medical Education and Research provide scientific support and they are involved in the teaching programme; the physicians formed in the course, once back in their Countries, are expected to facilitate training of the local staff (physicians, nurses and auxiliary personnel) and to continue collaboration; the project allows strengthening of partnerships with other Universities, Ministries, local and international Associations, NGO. The feedback of the participants who have attended the previous editions will also be discussed

Structure and Backbone Dynamics of Apo- and Holo-cellular Retinol-binding Protein in Solution

Retinoid-binding proteins play an important role in regulating transport, storage, and metabolism of vitamin A and its derivatives. The solution structure and backbone dynamics of rat cellular retinol-binding protein type I (CRBP) in the apo- and holo-form have been determined and compared using multidimensional high resolution NMR spectroscopy. The global fold of the protein is consistent with the common motif described for members of the intracellular lipid-binding protein family. The most relevant difference between the NMR structure ensembles of apo- and holoCRBP is the higher backbone disorder, in the ligand-free form, of some segments that frame the putative entrance to the ligand-binding site. These comprise alpha-helix II, the subsequent linker to beta-strand B, the hairpin turn between beta-strands C and D, and the betaE-betaF turn. The internal backbone dynamics, obtained from 15N relaxation data (T1, T2, and heteronuclear nuclear Overhauser effect) at two different fields, indicate several regions with significantly higher backbone mobility in the apoprotein, including the betaC-betaD and betaE-betaF turns. Although apoCRBP contains a binding cavity more shielded than that of any other retinoid carrier, conformational flexibility in the portal region may assist retinol uptake. The stiffening of the backbone in the holoprotein guarantees the stability of the complex during retinol transport and suggests that targeted retinol release requires a transiently open state that is likely to be promoted by the acceptor or the local environment

Modulating Ligand Dissociation through Methyl Isomerism in Accessory Sites: Binding of Retinol to Cellular Carriers

Due to the poor aqueous solubility of retinoids, evolution has tuned their binding to cellular proteins to address specialized physiological roles by modulating uptake, storage, and delivery to specific targets. With the aim to disentangle the structure-function relationships in these proteins and disclose clues for engineering selective carriers, the binding mechanism of the two most abundant retinol-binding isoforms was explored by using enhanced sampling molecular dynamics simulations and surface plasmon resonance. The distinctive dynamics of the entry portal site in the holo species was crucial to modulate retinol dissociation. Remarkably, this process is controlled at large extent by the replacement of Ile by Leu in the two isoforms, thus suggesting that a fine control of ligand release can be achieved through a rigorous selection of conservative mutations in accessory sites

Low Levels of Gastrin 17 are Related with Endoscopic Findings of Esophagitis and Typical Symptoms of GERD.

Background and Aims: In clinical practice, most patients with symptoms suggestive of gastroesophageal reflux disease (GERD) undergo esophago-gastro-duodenoscopy (EGD), despite its low sensitivity in detecting reflux stigmata. Gastrin 17 (G-17) has been proposed to be related with GERD, due to the negative feedback between acid secretion and this hormone. We assessed the clinical usefulness of fasting G-17 serum determination for a non-invasive diagnosis of GERD in patients with typical symptoms. Methods: We consecutively enrolled patients complaining of typical GERD symptoms in two different settings: a single referral center and a primary care setting. Control groups consisted of dyspeptic patients. All subjects underwent assessment of serum levels of G-17 and EGD. Results: At the academic hospital, 100 GERD patients (n=89 with erosive esophagitis and 11 with Barrett's esophagus) had statistically significant low levels of G-17 as compared with 184 dyspeptic patients (1.7±1.2 pg/L vs 8.9±5.7 pg/L p<0.0001). Similarly, in the primary care setting, 163 GERD patients had statistically significant low levels of G-17 as compared with 132 dyspeptic patients (0.5±0.2 pg/L vs. 4.0±2.6 pg/L, p<0.0001). Moreover, in the primary care setting, no statistically significant differences were found for G-17 levels between patients with erosive and non-erosive reflux pattern (0.4±0.2 vs 0.7±0.3; p=0.08). In primary care, the accuracy of G-17 less than 1 pg/L to diagnose non-invasively GERD was 94.3%. Conclusions: Low levels of G-17 were detected in patients with erosive esophagitis and Barrett's esophagus in a referral center and in patients with typical GERD symptoms in a sample of patients from a primary care setting

Stereospecific assignments of protein NMR resonances based on the tertiary structure and 2D/3D NOE data

In many cases of protein structure determination by NMR a high-quality structure is required. An important contribution to structural precision is stereospecific assignment of magnetically nonequivalent prochiral methylene and methyl groups, eliminating the need for introducing pseudoatoms and pseudoatom corrections in distance restraint lists. Here, we introduce the stereospecific assignment program that uses the resonance assignment, a preliminary 3D structure and 2D and/or 3D nuclear Overhauser effect spectroscopy peak lists for stereospecific assignment. For each prochiral group the algorithm automatically calculates a score for the two different stereospecific assignment possibilities, taking into account the presence and intensity of the nuclear Overhauser effect (NOE) peaks that are expected from the local environment of each prochiral group (i.e., the close neighbors). The performance of the algorithm has been tested and used on NMR data of -helical and -sheet proteins using homology models and/or X-ray structures. The program produced no erroneus stereospecific assignments provided the NOEs were carefully picked and the 3D model was sufficiently accurate. The set of NOE distance restraints produced by nmr2st using the results of the SSA module was superior in generating good-quality ensembles of NMR structures (low deviations from upper limits in conjunction with low root-mean-square-deviation values) in the first round of structure calculations. The program uses a novel approach that employs the entire 3D structure of the protein to obtain stereospecific assignment; it can be used to speed up the NMR structure refinement and to increase the quality of the final NMR ensemble even when no scalar or residual dipolar coupling information is available

Interactions of cytoplasmic retinol-binding proteins with phospholipid vesicles: insights into the physiological functions

Vitamin A plays a key role in vision, cell growth and differentiation. In the cell, retinol has several fates: (a) it can be stored as retinyl ester of fatty acids through the action of lecithin-retinol acyl transferase (LRAT) [1]; (b) most non-esterified retinol is bound to cellular carriers (CRBP); (c) it can enter the oxidative pathway for the synthesis of retinoic acid, through the action of retinol dehydrogenases (RDH) [2]. CRBP-I is ubiquitous, whereas the homologous CRBP-II is expressed solely in the enterocytes. Our current understanding of these processes remains largely incomplete, but there is evidence that the membrane-bound LRAT and RDH are inactive towards the protein/ligand complex, suggesting that the membrane microenvironment may trigger retinol transfer from the holo protein to the enzymes. To address this hypothesis we have performed a suite of NMR experiments with CRBP-I and CRBP-II in the presence of model membranes composed of either anionic or zwitterionic phospholipids, at varying protein:lipid molar ratios and ionic strength. The results will be discussed, in comparison with our previous data collected in buffer [3, 4]. All these studies may help to understand certain aspects of the physiological functions of CRBPs. [1] J. Amengual et al. J. Biol. Chem. 287, (2012) 24216-24227. [2] S. Portè et al. Chemico-Biological Interactions 202, (2013) 186-194. [3] T. Mittag, L. Franzoni et al. J. Am. Chem. Soc. 128, (2006) 9844-9848. [4] L. Franzoni et al. J. Lipid Res. 51, (2010) 1332-1343