Variability at different spatial scales of a coralligenous assemblage at Giannutri Island (Tuscan Archipelago,northwest Mediterranean)

This study was carried out on the rocky cliffs of Giannutri Island (Tyrrhenian Sea, Italy) to test the hypothesis that coralligenous assemblages are consistent within the bathymetric range considered (25–35 m depth) over three different spatial scales (1000 m, 100 m and 10 m). A multi-factorial sampling design was used to assess patterns of vertical distribution in the studied area. Data on the percent cover of algae and invertebrates were collected at three depths (25, 30 and 35 m) using a photographic method, and percentage cover was obtained using a visual method. Analysis of the results using ANOVA indicated that the distribution and abundance of algae and some invertebrates of the sublittoral assemblages are clearly heterogeneous. Algae, sponges and bryozoans showed significant variability in distribution and abundance at different depths, but this variability was not consistent amongst transects. Ascidians did not show any variability, while the abundance of anthozoans differed significantly amongst transects. We concluded that heterogeneity in the distribution and abundance of the taxa analysed is related to the smallest spatial scale investigated (10's of m). Some of the possible causes of the observed variability are discussed.     

Effect of High-Fidelity Simulation on Medical Students’ Knowledge about Advanced Life Support: A Randomized Study

High-fidelity simulation (HFS) is a learning method which has proven effective in medical education for technical and non-technical skills. However, its effectiveness for knowledge acquisition is less validated. We performed a randomized study with the primary aim of investigating whether HFS, in association with frontal lessons, would improve knowledge about advanced life support (ALS), in comparison to frontal lessons only among medical students. The secondary aims were to evaluate the effect of HFS on knowledge acquisition of different sections of ALS and personal knowledge perception. Participants answered a pre-test questionnaire consisting of a subjective (evaluating personal perception of knowledge) and an objective section (measuring level of knowledge) containing 100 questions about algorithms, technical skills, team working/early warning scores/communication strategies according to ALS guidelines. All students participated in 3 frontal lessons before being randomized in group S, undergoing a HFS session, and group C, receiving no further interventions. After 10 days from the end of each intervention, both groups answered a questionnaire (post-test) with the same subjective section but a different objective one. The overall number of correct answers of the post-test was significantly higher in group S (mean 74.1, SD 11.2) than in group C (mean 65.5, SD 14.3), p = 0.0017, 95% C.I. 3.34 – 13.9. A significantly higher number of correct answers was reported in group S than in group C for questions investigating knowledge of algorithms (p = 0.0001; 95% C.I 2.22–5.99) and team working/early warning scores/communication strategies (p = 0.0060; 95% C.I 1.13–6.53). Students in group S showed a significantly higher score in the post-test subjective section (p = 0.0074). A lower proportion of students in group S confirmed their perception of knowledge compared to group C (p = 0.0079). HFS showed a beneficial effect on knowledge of ALS among medical students, especially for notions of algorithms and team working/early warning scores/communication.     

Design and expression of peptides with antimicrobial activity against Salmonella typhimurium

We showed previously that insertion of Synechocystis Δ¹²‐desaturase in salmonella's membrane alters membrane physical state (MPS), followed by the expression of stress genes causing inability to survive within murine macrophages (MΦ). Recently, we showed that expression of one membrane lipid domain (MLD) of Δ¹²‐desaturase (ORF200) interferes with salmonella MPS, causing loss of virulence in mice and immunoprotection. Here, we postulate that an α‐antimicrobial peptide (α‐AMP) intercalates within membrane lipids, and depending on its amino acid sequence, it does so within specific key sensors of MLD. In this study, we choose as target for a putative synthetic AMP, PhoP/PhoQ, a sensor that responds to low Mg²⁺ concentration. We synthesised a modified DNA fragment coding for an amino acid sequence (NUF) similar to that fragment and expressed it in salmonella typhimurium. We showed that the pattern of gene expression controlled by PhoP/PhoQ highlights dysregulation of pathways involving phospholipids biosynthesis, stress proteins and genes coding for antigens. RNA‐Seq of strain expressing ORF200 showed that the pattern of those genes is also altered here. Accumulation of NUF conferred temporary immunoprotection. This represents a powerful procedure to address synthetic α‐AMPs to a specific MLD generating live non‐virulent bacterial strains.     

Human epicardium-derived cells fuse with high efficiency with skeletal myotubes and differentiate toward the skeletal muscle phenotype: a comparison study with stromal and endothelial cells

Recent studies have underscored a role for the epicardium as a source of multipotent cells. Here, we investigate the myogenic potential of adult human epicardium-derived cells (EPDCs) and analyze their ability to undergo skeletal myogenesis when cultured with differentiating primary myoblasts. Results are compared to those obtained with mesenchymal stromal cells (MSCs) and with endothelial cells, another mesodermal derivative. We demonstrate that EPDCs spontaneously fuse with pre-existing myotubes with an efficiency that is significantly higher than that of other cells. Although at a low frequency, endothelial cells may also contribute to myotube formation. In all cases analyzed, after entering the myotube, nonmuscle nuclei are reprogrammed to express muscle-specific genes. The fusion competence of nonmyogenic cells in vitro parallels their ability to reconstitute dystrophin expression in mdx mice. We additionally show that vascular cell adhesion molecule 1 (VCAM1) expression levels of nonmuscle cells are modulated by soluble factors secreted by skeletal myoblasts and that VCAM1 function is required for fusion to occur. Finally, treatment with interleukin (IL)-4 or IL-13, two cytokines released by differentiating myotubes, increases VCAM1 expression and enhances the rate of fusion of EPDCs and MSCs, but not that of endothelial cells.     

Long-term Sonographic and Serological Follow-up of Inactive Echinococcal Cysts of the Liver: Hints for a “Watch-and-Wait” Approach

Human cystic echinococcosis is a chronic, complex and neglected infection. Its clinical management has evolved over decades without adequate evaluation of efficacy. Recent expert opinion recommends that uncomplicated inactive cysts of the liver should be left untreated and solely monitored over time (“watch-and-wait” approach). However, clinical data supporting this approach are still scant and published mostly as conference proceedings. In this study, we report our experience with long-term sonographic and serological follow-up of inactive cysts of the liver. From March 1994 to October 2013, 38 patients with 47 liver cysts, diagnosed as inactive without any previous treatment history, were followed with ultrasound and serology at 6–12 months intervals for a period of at least 24 months (median follow-up 51.95 months) in our outpatient clinic. In 97.4% of patients, the cysts remained inactive over time and in only one case was reactivation of the cyst detected. No complications occurred during the time of monitoring. During follow-up, serology tests for CE were negative at diagnosis or became negative in 74.1% and were positive or became positive in 25.9% of cases. Patients with inactive cysts on ultrasound but positive serological tests were also investigated by CT scan (chest and abdomen) to rule out extra-hepatic cyst localization. This study confirms the importance of a stage-specific approach to the management of cystic echinococcosis and supports the use of a monitoring-only approach to inactive, uncomplicated cysts of the liver. It also confirms that serology plays only an ancillary role in the clinical management of these patients, compared to ultrasound and other imaging techniques. The implications of these findings for clinical management and natural history of cystic echinococcosis are discussed.     

Metabolic Profiling of Alternative NAD Biosynthetic Routes in Mouse Tissues

NAD plays essential redox and non-redox roles in cell biology. In mammals, its de novo and recycling biosynthetic pathways encompass two independent branches, the “amidated” and “deamidated” routes. Here we focused on the indispensable enzymes gating these two routes, i.e. nicotinamide mononucleotide adenylyltransferase (NMNAT), which in mammals comprises three distinct isozymes, and NAD synthetase (NADS). First, we measured the in vitro activity of the enzymes, and the levels of all their substrates and products in a number of tissues from the C57BL/6 mouse. Second, from these data, we derived in vivo estimates of enzymes''rates and quantitative contributions to NAD homeostasis. The NMNAT activity, mainly represented by nuclear NMNAT1, appears to be high and nonrate-limiting in all examined tissues, except in blood. The NADS activity, however, appears rate-limiting in lung and skeletal muscle, where its undetectable levels parallel a relative accumulation of the enzyme''s substrate NaAD (nicotinic acid adenine dinucleotide). In all tissues, the amidated NAD route was predominant, displaying highest rates in liver and kidney, and lowest in blood. In contrast, the minor deamidated route showed higher relative proportions in blood and small intestine, and higher absolute values in liver and small intestine. Such results provide the first comprehensive picture of the balance of the two alternative NAD biosynthetic routes in different mammalian tissues under physiological conditions. This fills a gap in the current knowledge of NAD biosynthesis, and provides a crucial information for the study of NAD metabolism and its role in disease.     

Pfannenstiel incision as an alternative approach for harvesting the rectus abdominis muscle for free-tissue transfer

The rectus abdominis muscle has been one of the most commonly used donor tissues for free-flap reconstruction of defects in the extremities and in selected head and neck patients. The rectus abdominis has provided adequate soft-tissue mass with predictable anatomy and results for the majority of its applications in free-flap reconstruction. Harvesting of this muscle has typically been done through a paramedian or midline incision, which has left a lengthy notable scar on a patient's abdomen. To avoid the late aesthetic deformity associated with this typical approach for the rectus abdominis, we began harvesting the muscle through a Pfannenstiel incision. Patients were initially selected based on young age and limited soft-tissue requirements. With additional experience, this technique was extended to include all healthy patients regardless of age. Also, soft-tissue limitations no longer became an issue, as we learned the entire rectus abdominis muscle could be harvested from this approach. An extended Pfannenstiel incision was made from the ipsilateral anterior superior iliac spine to the lateral border of the contralateral rectus abdominis. A superiorly based flap was raised to expose the full length of the anterior rectus sheath from pubis to costal margin. In our earlier patients, a periumbilical incision was made for presumed easier access, but we discovered this was an unnecessary maneuver. With the anterior sheath fully exposed, the muscle was harvested and the sheath repaired in a routine manner. The elevated abdominal flap was returned to its anatomic position and closed over a suction drain. Since 1993, 10 patients have undergone a Pfannenstiel approach for harvesting of the rectus abdominis muscle. The mean age was 16. The areas requiring coverage included a traumatic elbow defect, seven traumatic lower extremity defects, one lower extremity sarcoma defect, and one lower extremity septic joint defect. Mean follow-up for these patients was 12 months. There were no flap failures. One patient developed an arterial thrombosis on postoperative day 5 and was treated with successful revision. There were no abdominal wall complications. Cosmesis was judged as good in all patients. We would recommend avoiding this approach in heavy or moderate smokers, diabetic patients, and patients with significant obesity. The Pfannenstiel approach to the rectus abdominis muscle has allowed for complete harvest of the muscle, improved aesthetic results compared with alternative techniques, and avoidance of donor-site morbidityin healthy patients.