Velocity plateaus and jumps in carbon nanotube sliding

The friction between concentric carbon nanotubes sliding one inside the other has been widely studied and simulated, but not so far using external force as the driving variable. Our molecular dynamics (MD) simulations show that as the pulling force grows, the sliding velocity increases by jumps and plateaus rather than continuously as expected. Dramatic friction peaks (similar to that recently noted by Tangney {\it et al.} in Phys. Rev. Lett. 97 (2006) 195901) which develop around some preferential sliding velocities, are at the origin of this phenomenon. The (stable) rising edge of the peak produces a velocity plateau; the (unstable) dropping edge produces a jump to the nearest stable branch. The outcome is reminiscent of conduction in ionized gases, the plateau correspon ding to a current stabilization against voltage variations, the jump corresponding to a discharge or breakdown.Comment: 9 pages, 5 color figures, format latex Elsart. Surface Science, in press, http://dx.doi.org/10.1016/j.susc.2007.05.03

Short-Term Outcomes of Polycarbophil and Propionibacterium acnes Lysate Gel after Open Hemorrhoidectomy. A Prospective Cohort Study

Background: Pain is the most common complication after open excisional hemorrhoidectomy (OEH). We assessed the effectiveness of polycarbophil and Propionibacterium acnes lysate gel (Emorsan(R)Gel) on pain control after OEH. Research design and methods: Fifty consecutive patients undergoing OEH were included. All patients received stool softeners and oral analgesia in the post-operative period. Emorsan(R)Gel was also used topically by the last 25 patients (Emorsan(R)Gel group (EG)) until Post-Operative Day 20 (POD 20). The primary outcome was the effectiveness of Emorsan(R)Gel on pain relief using an 11-point visual analogue scale (VAS). Morbidity, wound healing (WH), and time to work were documented at POD 1, POD 10, POD 20, and POD 40. Results: Of the 50 patients enrolled, twenty-eight (56%) were males; median age, 49 (range, 28-73) years. The VAS score decreased over time in all patients, with significantly lower scores at POD 20 in the EG (1.44 (SD, 1.16) vs. 2.12 (0.93) in the control group (CG); p = 0.045). All patients in the EG achieved complete WH at last follow-up, compared to only 17 (68%) in the CG (p = 0.004). The likelihood of WH was 66% higher in the EG (OR, 1.66 [95%CI, 0.80-3.44; p = 0.172). Conclusions: Emorsan(R)Gel is safe and effective at reducing pain after EOH, promoting earlier WH compared to standard care treatment

Laparoscopic Right Colectomy. Intracorporeal Anastomosis Is Associated with Better Outcome

Colon cancer is the third most common cancer in man and woman in the developed world. Laparoscopic right colectomy is the standard of care for right colon cancer. Since the first report on laparoscopic approach in 1991, the surgical technique has been improved and currently all procedure is performed intracorporeally. The ileo-colic anastomosis can be performed either intracorporeal and extracorporeal: the differences in clinical outcome, complications rate, hospital stay and quality of life between that two techniques are not still clear and a large number of studies has been published about that. According to most recent meta-analysis, intracorporeal anastomosis have showed better outcome in anastomotic leakage rate, surgical site infection rate, development of incisional hernia, postoperative pain and recovery of gastrointestinal function

A functional assay for the clinical annotation of genetic variants of uncertain significance in Diamond\u2013Blackfan anemia

Diamond-Blackfan anemia (DBA) is a rare genetic hypoplasia of erythroid progenitors characterized by mild to severe anemia and associated with congenital malformations. Clinical manifestations in DBA patients are quite variable and genetic testing has become a critical factor in establishing a diagnosis of DBA. The majority of DBA cases are due to heterozygous loss-of-function mutations in ribosomal protein (RP) genes. Causative mutations are fairly straightforward to identify in the case of large deletions and frameshift and nonsense mutations found early in a protein coding sequence, but diagnosis becomes more challenging in the case of missense mutations and small in-frame indels. Our group recently characterized the phenotype of lymphoblastoid cell lines established from DBA patients with pathogenic lesions in RPS19 and observed that defective pre-rRNA processing, a hallmark of the disease, was rescued by lentiviral vectors expressing wild-type RPS19. Here, we use this complementation assay to determine whether RPS19 variants of unknown significance are capable of rescuing pre-rRNA processing defects in these lymphoblastoid cells as a means of assessing the effects of these sequence changes on the function of the RPS19 protein. This approach will be useful in differentiating pathogenic mutations from benign polymorphisms in identifying causative genes in DBA patients

Efficacy and safety of Propionibacterium extract gel versus glyceryl trinitrate ointment in the treatment of chronic anal fissure: a randomized controlled trial

Aim: Chronic anal fissure (CAF) is an extremely frequent finding in clinical practice. Several topical agents have been proposed for its treatment with the common goal of increasing anodermal blood flow to promote healing. The aim of this study was to compare the efficacy and safety of a Propionibacterium extract gel (PeG) and 0.4% glyceryl trinitrate ointment (GTN) in patients with CAF.Method: Patients were randomly allocated to a PeG or GTN group and medication was administered every 12 h for 40 days. The primary outcome was the success rate, as measured by a decrease in the REALISE scoring system for anal fissure at 10, 20 and 40 days after initiating either treatment. The secondary outcomes recorded at the same time points were healing rate, visual analogue scales for itching and burning, rate of complications and adverse events, patient quality of life and satisfaction, and cost analysis.Results: A total of 120 patients were enrolled, and 96 patients (PeG, n = 53; GTN, n = 43) completed the primary outcomes. A significant decrease over time in the REALISE score was observed in both groups. Adverse events occurred more frequently in the GTN group than in the PeG group, peaking at visit 1 [37 (63.8%) vs. 2 (3.4%), respectively], with headache being the most prevalent. The between-treatment cumulative average costs per patient were significantly higher for GTN than that for PeG at each follow-up visit. There were no other significant differences between the two groups for any of the other outcomes.Conclusion: While there was no difference in healing rates between the two treatments, PeG was more cost-effective and associated with fewer adverse events

Lymphoblastoid cell lines from Diamond Blackfan anaemia patients exhibit a full ribosomal stress phenotype that is rescued by gene therapy

Diamond Blackfan anaemia (DBA) is a congenital bone marrow failure syndrome characterised by selective red cell hypoplasia. DBA is most often due to heterozygous mutations in ribosomal protein (RP) genes that lead to defects in ribosome biogenesis and function and result in ribosomal stress and p53 activation. The molecular mechanisms underlying this pathology are still poorly understood and studies on patient erythroid cells are hampered by their paucity. Here we report that RP-mutated lymphoblastoid cell lines (LCLs) established from DBA patients show defective rRNA processing and ribosomal stress features such as reduced proliferation, decreased protein synthesis, and activation of p53 and its target p21. These phenotypic alterations were corrected by gene complementation. Our data indicate that DBA LCLs could be a useful model for molecular and pharmacological investigations

Towards an AMTEC-like device based on non-alkali metal for efficient, safe and reliable direct conversion of thermal to electric power

Alkali Metal ThermoElectric Converters directly convert heat into electric energy and have promising applicability in the field of sustainable and renewable energy. The high theoretical efficiency, close to Carnot's cycle, the lack of moving parts, and the interesting operating temperature range drive the search for new materials able to ensure safe and reliable operation at competitive costs.The present work focuses on the design of a non-alkali metal based cell and on the fabrication of a testing device to validate the design work. The selection of a new operating fluid for the cell improves durability, reliability and safety of the device. Finally, we discuss possible applications to already existing thermal energy sources

Human Haemato-Endothelial Precursors: Cord Blood CD34+ Cells Produce Haemogenic Endothelium

Embryologic and genetic evidence suggest a common origin of haematopoietic and endothelial lineages. In the murine embryo, recent studies indicate the presence of haemogenic endothelium and of a common haemato-endothelial precursor, the haemangioblast. Conversely, so far, little evidence supports the presence of haemogenic endothelium and haemangioblasts in later stages of development. Our studies indicate that human cord blood haematopoietic progenitors (CD34+45+144-), triggered by murine hepatocyte conditioned medium, differentiate into adherent proliferating endothelial precursors (CD144+CD105+CD146+CD31+CD45-) capable of functioning as haemogenic endothelium. These cells, proven to give rise to functional vasculature in vivo, if further instructed by haematopoietic growth factors, first switch to transitional CD144+45+ cells and then to haematopoietic cells. These results highlight the plasticity of haemato-endhothelial precursors in human post-natal life. Furthermore, these studies may provide highly enriched populations of human post-fetal haemogenic endothelium, paving the way for innovative projects at a basic and possibly clinical level. \uc2\ua9 2012 Pelosi et al

Dispositivo per la conversione di energia, sistema di conversione di energia e relativo procedimento di conversione di energia

Viene descritto un dispositivo di conversione di energia comprendente: - una prima riserva avente un primo volume per un fluido di lavoro, - una seconda riserva avente un secondo volume per il fluido di lavoro, - almeno un’interfaccia selettivamente permeabile, pervia rispetto a ioni di detto fluido di lavoro, realizzante una comunicazione di fluido fra detta prima riserva e detta seconda riserva, detta interfaccia selettivamente permeabile includendo un elettrolita solido, in cui a ciascuna interfaccia selettivamente permeabile sono accoppiati un primo elettrodo esposto a detto primo volume, e un secondo elettrodo esposto a detto secondo volume, in cui detto secondo elettrodo è disposto da una parte opposta dell’interfaccia selettivamente permeabile rispetto al primo elettrodo

Choice of Alternative Polyadenylation Sites, Mediated by the RNA-Binding Protein Elavl3, Plays a Role in Differentiation of Inhibitory Neuronal Progenitors

Alternative polyadenylation (APA) is a widespread mechanism involving about half of the expressed genes, resulting in varying lengths of the 3′ untranslated region (3′UTR). Variations in length and sequence of the 3′UTR may underlie changes of post-transcriptional processing, localization, miRNA targeting and stability of mRNAs. During embryonic development a large array of mRNAs exhibit APA, with a prevalence of the longer 3′UTR versions in differentiating cells. Little is known about polyA+ site usage during differentiation of mammalian neural progenitors. Here we exploit a model of adherent neural stem (ANS) cells, which homogeneously and efficiently differentiate into GABAergic neurons. RNAseq data shows a global trend towards lengthening of the 3′UTRs during differentiation. Enriched expression of the longer 3′UTR variants of Pes1 and Gng2 was detected in the mouse brain in areas of cortical and subcortical neuronal differentiation, respectively, by two-probes fluorescent in situ hybridization (FISH). Among the coding genes upregulated during differentiation of ANS cells we found Elavl3, a neural-specific RNA-binding protein homologous to Drosophila Elav. In the insect, Elav regulates polyA+ site choice while interacting with paused Pol-II promoters. We tested the role of Elavl3 in ANS cells, by silencing Elavl3 and observed consistent changes in 3′UTR length and delayed neuronal differentiation. These results indicate that choice of the polyA+ site and lengthening of 3′UTRs is a possible additional mechanism of posttranscriptional RNA modification involved in neuronal differentiation