A FAST SEMI-ANALYTICAL METHOD FOR COMPUTING THE RESPONSE OF RAILWAY TRACKS ON NONLINEAR FOUNDATIONS

International audienceThe nonlinear vibration of railway tracks is a subject of some recent investigations. A main source of non-linearity comes from the railway foundations. For example, ballast and its lower layers or support systems of non-ballasted railway could have nonlinear behaviors. Models of beam under moving forces are often used for this dynamic system, and then the models are solved by numerical method or perturbation technique for some special nonlinear cases. This communication present a new method for calculating the response of railway tracks under moving trains loads. Based an analytical model of periodically supported beam, this model holds for all kinds of nonlinear foundations. Then, by using harmonic balance techniques and iteration procedures, a new method is developed to calculate the response of the model provided that the loading forces form a periodic impulse series. This kind of loading force represents charges of moving trains with equal mass wagons. This method is demonstrated to converge to the analytic solution of the model in case of linear foundation. Then, it is applied to bilinear and nonlinear foundation as examples. The results show that the nonlinear parameters of foundation have a strong influence on the railways track responses. This semi-analytical method is simple and could be efficient to compute the nonlinear vibrations of railway tracks

Eculizumab in paraxysmal nocturnal haemogloburinia and atypical haemolytic syndrome 10-year pharmacovigilance analysis

Eculizumab is the first and only medication approved for paroxysmal nocturnal haemoglobinuria (PNH) and atypical haemolytic uraemic syndrome (aHUS) treatment. However, eculizumab safety based on long‐term pharmacovigilance is unknown. This analysis summarises safety data collected from spontaneous and solicited sources from 16 March 2007 through 1 October 2016. Cumulative exposure to eculizumab was 28 518 patient‐years (PY) (PNH, 21 016 PY; aHUS, 7502 PY). Seventy‐six cases of meningococcal infection were reported (0·25/100 PY), including eight fatal PNH cases (0·03/100 PY). Susceptibility to meningococcal infections remained the key risk in patients receiving eculizumab. The meningococcal infection rate decreased over time; related mortality remained steady. The most commonly reported serious nonmeningococcal infections were pneumonia (11·8%); bacteraemia, sepsis and septic shock (11·1%); urinary tract infection (4·1%); staphylococcal infection (2·6%); and viral infection (2·5%). There were 434 reported cases of eculizumab exposure in pregnant women; of 260 cases with known outcomes, 70% resulted in live births. Reporting rates for solid tumours (≈0·6/100 PY) and haematological malignancies (≈0·74/100 PY) remained stable over time. No new safety signals affecting the eculizumab benefit‐risk profile were identified. Continued awareness and implementation of risk mitigation protocols are essential to minimise risk of meningococcal and other Neisseria infections in patients receiving eculizumab

Breast Cancer Exosome-like Microvesicles and Salivary Gland Cells Interplay Alters Salivary Gland Cell-Derived Exosome-like Microvesicles In Vitro

Saliva is a useful biofluid for the early detection of disease, but how distal tumors communicate with the oral cavity and create disease-specific salivary biomarkers remains unclear. Using an in vitro breast cancer model, we demonstrated that breast cancer-derived exosome-like microvesicles are capable of interacting with salivary gland cells, altering the composition of their secreted exosome-like microvesicles. We found that the salivary gland cells secreted exosome-like microvesicles encapsulating both protein and mRNA. We also showed that the interaction with breast cancer-derived exosome-like microvesicles communicated and activated the transcriptional machinery of the salivary gland cells. Thus, the interaction altered the composition of the salivary gland cell-derived exosome-like microvesicles on both the transcriptomically and proteomically

Exosomes Communicate Protective Messages during Oxidative Stress; Possible Role of Exosomal Shuttle RNA

BACKGROUND: Exosomes are small extracellular nanovesicles of endocytic origin that mediate different signals between cells, by surface interactions and by shuttling functional RNA from one cell to another. Exosomes are released by many cells including mast cells, dendritic cells, macrophages, epithelial cells and tumour cells. Exosomes differ compared to their donor cells, not only in size, but also in their RNA, protein and lipid composition. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we show that exosomes, released by mouse mast cells exposed to oxidative stress, differ in their mRNA content. Also, we show that these exosomes can influence the response of other cells to oxidative stress by providing recipient cells with a resistance against oxidative stress, observed as an attenuated loss of cell viability. Furthermore, Affymetrix microarray analysis revealed that the exosomal mRNA content not only differs between exosomes and donor cells, but also between exosomes derived from cells grown under different conditions; oxidative stress and normal conditions. Finally, we also show that exposure to UV-light affects the biological functions associated with exosomes released under oxidative stress. CONCLUSIONS/SIGNIFICANCE: These results argue that the exosomal shuttle of RNA is involved in cell-to-cell communication, by influencing the response of recipient cells to an external stress stimulus

High Levels of Exosomes Expressing CD63 and Caveolin-1 in Plasma of Melanoma Patients

BACKGROUND: Metastatic melanoma is an untreatable cancer lacking reliable and non-invasive markers of disease progression. Exosomes are small vesicles secreted by normal as well as tumor cells. Human tumor-derived exosomes are involved in malignant progression and we evaluated the presence of exosomes in plasma of melanoma patients as a potential tool for cancer screening and follow-up. METHODOLOGY/PRINCIPAL FINDINGS: We designed an in-house sandwich ELISA (Exotest) to capture and quantify exosomes in plasma based on expression of housekeeping proteins (CD63 and Rab-5b) and a tumor-associated marker (caveolin-1). Western blot and flow cytometry analysis of exosomes were used to confirm the Exotest-based findings. The Exotest allowed sensitive detection and quantification of exosomes purified from human tumor cell culture supernatants and plasma from SCID mice engrafted with human melanoma. Plasma levels of exosomes in melanoma-engrafted SCID mice correlated to tumor size. We evaluated the levels of plasma exosomes expressing CD63 and caveolin-1 in melanoma patients (n = 90) and healthy donors (n = 58). Consistently, plasma exosomes expressing CD63 (504+/-315) or caveolin-1 (619+/-310) were significantly increased in melanoma patients as compared to healthy donors (223+/-125 and 228+/-102, respectively). While the Exotest for CD63+ plasma exosomes had limited sensitivity (43%) the Exotest for detection of caveolin-1+ plasma exosomes showed a higher sensitivity (68%). Moreover, caveolin-1+ plasma exosomes were significantly increased with respect to CD63+ exosomes in the patients group. CONCLUSIONS/SIGNIFICANCE: We describe a new non-invasive assay allowing detection and quantification of human exosomes in plasma of melanoma patients. Our results suggest that the Exotest for detection of plasma exosomes carrying tumor-associated antigens may represent a novel tool for clinical management of cancer patients

Nanovesicles from Malassezia sympodialis and Host Exosomes Induce Cytokine Responses – Novel Mechanisms for Host-Microbe Interactions in Atopic Eczema

BACKGROUND: Intercellular communication can occur via the release of membrane vesicles. Exosomes are nanovesicles released from the endosomal compartment of cells. Depending on their cell of origin and their cargo they can exert different immunoregulatory functions. Recently, fungi were found to produce extracellular vesicles that can influence host-microbe interactions. The yeast Malassezia sympodialis which belongs to our normal cutaneous microbial flora elicits specific IgE- and T-cell reactivity in approximately 50% of adult patients with atopic eczema (AE). Whether exosomes or other vesicles contribute to the inflammation has not yet been investigated. OBJECTIVE: To investigate if M. sympodialis can release nanovesicles and whether they or endogenous exosomes can activate PBMC from AE patients sensitized to M. sympodialis. METHODS: Extracellular nanovesicles isolated from M. sympodialis, co-cultures of M. sympodialis and dendritic cells, and from plasma of patients with AE and healthy controls (HC) were characterised using flow cytometry, sucrose gradient centrifugation, Western blot and electron microscopy. Their ability to stimulate IL-4 and TNF-alpha responses in autologous CD14, CD34 depleted PBMC was determined using ELISPOT and ELISA, respectively. RESULTS: We show for the first time that M. sympodialis releases extracellular vesicles carrying allergen. These vesicles can induce IL-4 and TNF-α responses with a significantly higher IL-4 production in patients compared to HC. Exosomes from dendritic cell and M. sympodialis co-cultures induced IL-4 and TNF-α responses in autologous CD14, CD34 depleted PBMC of AE patients and HC while plasma exosomes induced TNF-α but not IL-4 in undepleted PBMC. CONCLUSIONS: Extracellular vesicles from M. sympodialis, dendritic cells and plasma can contribute to cytokine responses in CD14, CD34 depleted and undepleted PBMC of AE patients and HC. These novel observations have implications for understanding host-microbe interactions in the pathogenesis of AE

The present and future of serum diagnostic tests for testicular germ cell tumours.

Testicular germ cell tumours (GCTs) are the most common malignancy occurring in young adult men and the incidence of these tumours is increasing. Current research priorities in this field include improving overall survival for patients classified as being 'poor-risk' and reducing late effects of treatment for patients classified as 'good-risk'. Testicular GCTs are broadly classified into seminomas and nonseminomatous GCTs (NSGCTs). The conventional serum protein tumour markers α-fetoprotein (AFP), human chorionic gonadotrophin (hCG) and lactate dehydrogenase (LDH) show some utility in the management of testicular malignant GCT. However, AFP and hCG display limited sensitivity and specificity, being indicative of yolk sac tumour (AFP) and choriocarcinoma or syncytiotrophoblast (hCG) subtypes. Furthermore, LDH is a very nonspecific biomarker. Consequently, seminomas and NSGCTs comprising a pure embryonal carcinoma subtype are generally negative for these conventional markers. As a result, novel universal biomarkers for testicular malignant GCTs are required. MicroRNAs are short, non-protein-coding RNAs that show much general promise as biomarkers. MicroRNAs from two 'clusters', miR-371-373 and miR-302-367, are overexpressed in all malignant GCTs, regardless of age (adult or paediatric), site (gonadal or extragonadal) and subtype (seminomas, yolk sac tumours or embryonal carcinomas). A panel of four circulating microRNAs from these two clusters (miR-371a-3p, miR-372-3p, miR-373-3p and miR-367-3p) is highly sensitive and specific for the diagnosis of malignant GCT, including seminoma and embryonal carcinoma. In the future, circulating microRNAs might be useful in diagnosis, disease monitoring and prognostication of malignant testicular GCTs, which might also reduce reliance on serial CT scanning. For translation into clinical practice, important practical considerations now need addressing.The authors would like to acknowledge grant funding from CwCUK/GOSHCC (M.J.M. N.C. grant W1058), SPARKS (M.J.M. N.C. grant 11CAM01), CRUK (N.C. grant A13080) MRC (M.J.M. grant MC_EX_G0800464) and National Health Service funding to the Royal Marsden/Institute of Cancer Research National Institute for Health Research Biomedical Research Centre for Cancer (R.A.H.). The authors also thank the Max Williamson Fund, the Josh Carrick Foundation and The Perse Preparatory School, Cambridge for support.This is the author accepted manuscript. The final version is available fromNature Publishing Group via https://doi.org/10.1038/nrurol.2016.17

The morphology and biochemistry of nanostructures provide evidence for synthesis and signaling functions in human cerebrospinal fluid

<p>Abstract</p> <p>Background</p> <p>Cerebrospinal fluid (CSF) contacts many brain regions and may mediate humoral signaling distinct from synaptic neurotransmission. However, synthesis and transport mechanisms for such signaling are not defined. The purpose of this study was to investigate whether human CSF contains discrete structures that may enable the regulation of humoral transmission.</p> <p>Methods</p> <p>Lumbar CSF was collected prospectively from 17 participants: with no neurological or psychiatric disease, with Alzheimer's disease, multiple sclerosis, or migraine; and ventricular CSF from two cognitively healthy participants with long-standing shunts for congenital hydrocephalus. Cell-free CSF was subjected to ultracentrifugation to yield supernatants and pellets that were examined by transmission electron microscopy, shotgun protein sequencing, electrophoresis, western blotting, lipid analysis, enzymatic activity assay, and immuno-electron microscopy.</p> <p>Results</p> <p>Over 3,600 CSF proteins were identified from repeated shotgun sequencing of cell-free CSF from two individuals with Alzheimer's disease: 25% of these proteins are normally present in membranes. Abundant nanometer-scaled structures were observed in ultracentrifuged pellets of CSF from all 16 participants examined. The most common structures included synaptic vesicle and exosome components in 30-200 nm spheres and irregular blobs. Much less abundant nanostructures were present that derived from cellular debris. Nanostructure fractions had a unique composition compared to CSF supernatant, richer in omega-3 and phosphoinositide lipids, active prostanoid enzymes, and fibronectin.</p> <p>Conclusion</p> <p>Unique morphology and biochemistry features of abundant and discrete membrane-bound CSF nanostructures are described. Prostaglandin H synthase activity, essential for prostanoid production and previously unknown in CSF, is localized to nanospheres. Considering CSF bulk flow and its circulatory dynamics, we propose that these nanostructures provide signaling mechanisms <it>via </it>volume transmission within the nervous system that are for slower, more diffuse, and of longer duration than synaptic transmission.</p

Immediate vs. deferred switching from a boosted protease inhibitor (PI/r) based regimen to a Dolutegravir (DTG) based regimen in virologically suppressed patients with high cardiovascular risk or Age ≥50 years: final 96 weeks results of NEAT 022 study

Background Both immediate and deferred switching from a ritonavir-boosted protease inhibitor (PI/r)–based regimen to a dolutegravir (DTG)–based regimen may improve lipid profile. Methods European Network for AIDS Treatment 022 Study (NEAT022) is a European, open-label, randomized trial. Human immunodeficiency virus (HIV)–infected adults aged ≥50 years or with a Framingham score ≥10% were eligible if HIV RNA was <50 copies/mL. Patients were randomized to switch from PI/r to DTG immediately (DTG-I) or to deferred switch at week 48 (DTG-D). Week 96 endpoints were proportion of patients with HIV RNA <50 copies/mL, percentage change of lipid fractions, and adverse events (AEs). Results Four hundred fifteen patients were randomized: 205 to DTG-I and 210 DTG-D. The primary objective of noninferiority at week 48 was met. At week 96, treatment success rate was 92.2% in the DTG-I arm and 87% in the DTG-D arm (difference, 5.2% [95% confidence interval, –.6% to 11%]). There were 5 virological failures in the DTG-I arm and 5 (1 while on PI/r and 4 after switching to DTG) in the DTG-D arm without selection of resistance mutations. There was no significant difference in terms of grade 3 or 4 AEs or treatment-modifying AEs. Total cholesterol and other lipid fractions (except high-density lipoprotein) significantly (P < .001) improved both after immediate and deferred switching to DTG overall and regardless of baseline PI/r strata. Conclusions Both immediate and deferred switching from a PI/r to a DTG regimen in virologically suppressed HIV-infected patients ≥50 years old or with a Framingham score ≥10% was highly efficacious and well tolerated, and improved the lipid profile

Conservation of geosites as a tool to protect geoheritage: the inventory of Ceará Central Domain, Borborema Province - NE/Brazil

The Ceará Central Domain, in the northern Borborema Province/NE Brazil, encompasses important geological records (geosites) which allow understanding a relevant period of the Earth’s evolution, mainly associated to Neoproterozoic Brazilian/Pan-African Cycle and West Gondwana amalgamation, besides Neoarchean to Ordovician records. The presented geoheritage inventory aims to characterise the geosites with scienti c relevance of Ceará Central Domain. By applying a method for large areas, the nal selection resulted in eight geological frameworks represented by 52 geosites documented in a single database. This is the rst step for a geoconservation strategy based on systematic inventories, statutory protection, geoethical behaviour and awareness about scienti c, educational and/or cultural relevance of geosites.We specially thank all experts that helped us with this inventory: Afonso Almeida, Carlos E.G. de Araújo, César Veríssimo, Christiano Magini, Clóvis Vaz Parente, Felipe G. Costa, Irani C. Mattos, Neivaldo de Castro, Otaciel de Melo, Sebástian G. Chiozza, Ticiano Santos and Stefano Zincone. We are also thankful to Kátia Mansur, Ricardo Fraga Pereira and anonymous reviewers for their valuable contributions. PM is grateful to Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) for PhD mobility scholarship PDSE Program/Process n 88881.132168/2016-01info:eu-repo/semantics/publishedVersio